1ST  ISSUED   NOV 12  privately...

1.  REVIEW  OF SUMMER  2007  FORECAST 8.  ENSO  FORECAST FROM   CLIMATE MODELS
2.    BOTTOM LINE    9.    MEI
3.   KEY ASPECTS   TO WINTER  2007-08 10   HURRICANE  SEASON 2007
4.    FORECAST MAPS 11   NAO
5.  HOW   WAS THIS  FORECAST PREPARED 12   PDO
6.  AUTUMN 2007   PATTERN 13  QBO
7   EL NINO STATUS  2007-08 14    SNOW  COVER


This forecast    has been delayed a  bit  because of  the  impending  move  from my current location   to    Near Leesburg   VA at the end of NOV   2006.   Clients get it first...   then the web site and the general public  but with the move   well something  was going to delayed.    Pull up  a  Hot  cup of  Tea and    some  cake. 

Text  that is  in  RED   BOLD  has been   so designated   because   it contains   KEY ideas.

 Throughout this  forecast      you will see   the  acronym    "CF" used.   The two   letters   "CF"     stands  for    "Consensus Forecast"    which is  term that I use   to describe  the general view or a summary of what most  PWSIP  (private weather  service  Information Services)      and / or    NWS forecasters are saying.  The CF is very important in determining how the seasonal trade in Energy and Agriculture markets will unfold as well the operational side of the weather biz.       For example… State DOTs will often significantly lower their Salt and Sand purchases if the CF is for a Mild winter in their areas.       The CF often consists of  

a) the CPC (Climate Prediction Center) …whose forecast carry a lot of weight...  
b) large well known Private Weather Service Information Provider (PWSIPs) and      
c) some well known Energy/ Ag forecasters.

 

 

REVIEW   of   SUMMER  2007




After careful consideration I have come to the conclusion that the WxRisk Summer forecast of 20076 was OK but not my best....  the Summer  2006   Seasonal Forecast was far better.   My   JUNE 2007
was Not  good as I missed the     rainy pattern and cool temps over the  central and Lower Plains  and I was too  cold over the Midwest and Northeast  but I did  get the  heat over the  western CONUS.   JULY 2007  also less than a  good forecast as well.. again I was too cold over the Midwest and Northeast  and way too dry over the Lower Plains   but I did get the  extreme heat over the   Western CONUS.  AUGUST  2007   was my   best   month as I got the heat   over the  Deep South and Lower Midwest almost   perfectly.

The Hurricane  forecast   for 2007 was    again    Fabulous.... as good  as  my  2006   Hurricane forecast ( where I went for only  12  named  TCs).   for 2007  I said this

This time around WxRisk.com does see an  INCREASED   probability  of  significantly More  active Hurricane season for 2007.   However where I disagree with the Consensus Forecasts  is the    matter   of which   regions of  the    US Coasts   are more likely to be hit.... ( Gulf / Florida / SE US coast / NE US CONUS).    I see a much reduced chance of the central and northern portions of the Texas coast being hit this year....as well as the central and eastern  Gulf  as well as the   SE Coast.   But There  is an increased chance of areas from Brownsville /southern TX   southward  into northern Mexico getting hit ... Nor do I see    the  2007 Hurricane as  a  New England    year either...

click  in IMAGE  to see   map

 

ok  BUT  NOT MY BEST--- sUMMER arguably the best seasonal forecast I had ever issued  on this web site over the past six or seven years. And quite frankly from what I've seen from every else's forecasts... it appears that my Summer 2006 forecast was best one out there. Period.

Without going into a lot a detail because I simply don't wish to... suffice to say my Summer forecast has generated quite a bit of reaction and business from the various Energy and Ag markets.. trading houses and traders ... which makes me happy.

In my  Summer 2006 forecast ...which again you can see at this LINK... I argued that the

 

JET STREAM MAPS
JUNE JULY AUGUST
  TEMPERATURE  MAPS
JUNE JULY AUGUST
RAINFALL   MAPS
JUNE JULY AUGUST
  ACTUAL    JUNE TEMPS ACTUAL    JULY  TEMPS ACTUAL    AUG TEMPS
ACTUAL    JUNE PRECIP ACTUAL    JULY  PRECIP ACTUAL    AUG PRECIP

 

 

 

 

 

THE  BOTTOM  LINE 

******* There will be  a  MID WINTER    UPDATE      JAN 15*****

The Winter of 2007-2008 is going to be a mild Winter for most of the CONUS but it will be an active Winter as well.   The West Coast  (especially the Pacific Northwest)   as well as most Rockies and Upper Plains  will see the most active  of the Winter weather and has the best chance of seeing temperatures Below Normal.   For most of the Winter the Central Plains --  OK  to  NEB --   as  well as Midwest   is going to be  the  "battleground"  while the Deep South will feature  dry conditions and abnormally warm temperatures. In the Northeast US....  New England should see temperatures somewhat Above Normal  in the  General sense but  there will be   significant  cold intervals as well.   However the Middle Atlantic states including the big cities of the I-95 corridor from New York down to Richmond will see several bouts of   Above  and   Much  Above Normal temperatures.

 

The pattern will bear a striking resemblance to the Winter of 2005 -- 2006 and the Winter of 1970-71. In many ways this Winter will be a compromise between the two since I do not see the Winter 2007 -- 2008 as being as warm as the 05-06 Winter and not as cold or a snowy as the 70-71 Winter .

 

For those that have read my seasonal  forecasts  before  you know   that  there have been times  when  I have gone against the CF or consensus forecast   ( Hurricane season 2006   Winter  2005-06  just to name a few) ...    I have done so   with good reason and for the most part  those contrarian Winter and Summer forecasts worked out quite well.   However in this particular instance   -- the   Winter   20007-08 forecast --  I think the CF  (consensus forecast)  is going to be correct.   That being said there are some surprises and issues which have to be dealt with.    As a general  rule   there have some  improvements over the last 10 years with regard to seasonal forecasting.   But  one the major sticking points I have with seasonal forecasts whether they are government or private forecasts   is that there is too much focus on    question   of  which areas  will see Above Normal  or Below Normal Temps  or the  precipitation  question and not  emphasis on  the underlying features.  WxRisk  seasonal  forecasts  are  premised on the idea that by focusing on more  underlying large scale weather features  a  more complete  picture or  "paradigm"    develops.  That is to say a more complete scenario of how of  the upcoming forecast is formed. The advantage  in doing   a season  forecast in this manner  is that it enables a forecaster to stay on top of any changes or surprises that might be developing as the  season  begins to reveal itself.

In the general sense the overall Winter pattern for 2007 -- 08 is going to feature the mean trough position being located  either over the  far eastern  Pacific /West Coast or the western third of North America and a mean Ridge position over the Southeast US.  The combination of these stronger than normal Pacific Jet stream... the typical climatalogical pattern one sees with a Moderate La Nina.... the pool of anomalously cold sea surface temperatures over the eastern Pacific (negative phase of the PDO)   and the effect of the extremely strong easterly phase QBO    (reminiscent of what we saw in the autumn of 2005)  will all contribute to ensure that the mean proposition is going to be located over the western portions of North America/ West Coast of the CONUS.

Since the basic laws of physics and meteorology say that for every Ridge position there must also be a trough.... the placement of the mean trough position over the West Coast means that   "downstream"   there must be a corresponding Ridge. That Ridge CAN be located somewhere between the Plains and Bermuda.

What determines  WHERE   this downstream Ridge position " sets  up"   can be several  factors. However going into the  Winter of  2007-8   we have an important and unusual feature which does not typically exists going into the Winter months. I am referring to the large and  intense area of the drought over the Southeast CONUS.

It is the position of  WxRisk    forecast  that  the Winter of 2007 -- 08 that the interaction between  above  mentioned seasonal  factors  ( Moderate La Nina  Very  strong -QBO  -PDO    and  the  late Autumn pattern)     along  with the large drought area over the Southeast will ensure that the downstream Ridge position.... which could be located anywhere from the Lower Plains east towards Bermuda... is going to  "Lock  in"  the mean Ridge position over the Southeast for much of this Winter.

 

There will of course be times when the Mean southeast US Ridge is almost nonexistent or playing a minimal role in the overall pattern. But on a large scale or seasonal perspective the ridge will be an important feature for this Winter.

 

FORECAST MAPS

DEC  2007  JET STREAM DEC  2007  PRECIP DEC  2007  TEMPS
JAN 2008  JET STREAM JAN 2008    PRECIP JAN  2008  TEMPS
FEB 2008  JET STREAM FEB 2008 PRECIP FEB 2008  TEMPS

 

Finally in the WHAT CAN WRONG ? department  my focus  is on during the middle and second-half of the Winter.  It is possible that the moderate La Nina may continue right through the heart of  Winter  and not begin to break down until late March or April. If that is the case there is not going to be any significant change  to the overall pattern in mid-or late February.

Another concern has to be the  weakening of  the strong easterly phase of the QBO which may occur late in the Winter and Spring 2008. The question is whether or not the weakening of the QBO will occur in time to affect the last third or 25% of the Winter season.

And lastly the October monthly reading of the NAO was positive. There is some indication that suggests a correlation between the October NAO phase and the inverse or opposite phase during the Winter months. If during the Winter months there is a sustained negative phase of the NAO over Canada and Greenland... there could be major shift in the overall pattern with the Northeast US turning quite stormy and cold.

 

KEY ASPECTS OF THE COMING WINTER

 

CRITICAL  ASSUMPTIONS 

There are several critical assumptions which ALL  extended and long-range and seasonal forecasts are based upon. By emphasizing these features it becomes possible to develop that large-scale view of how I see the season unfolding and what to expect with trends. In the   Winter of  2007-87   these   Critical   features will be:

LA NINA... Currently the  Moderate La Nina  that  has  developed in  AUG   had  held  steady at  Moderate  levels  from Early  OCT   thru Mid Nov   2007.  The Moderate La Nina will hold its intensity   through  Mid  Jan...possibly   later.  There  is also the  issue of   when and How the  La Nina decays   from Moderate    to Weak  intensity  which could    have   significant impact  late in the  Winter and early in the  Spring  of 2008.

 

QBO  --    the  QBO is  currently in  the extreme  Negative Phase   (blowing  from West to East).  Its  two most  recent readings  (Sept   and   Oct 2008)  is the  2nd   most intense  East  QBO values  ever  recorded  and  and  are a  very close match  to the  Most   intense  East QBO  phase    of all time  ( Sept / Oct /  Nov 2005).    Moderately   strong East QBO   events strongly   support   Blocking  patterns  over the  North America  but  severely  negative  QBO values  strongly  support  progressive   weather patterns... restrict  large scale  Arctic  outbreaks and often play Havoc  with Model performance  in  the week 2 time frame .   More details  on this will be provides in the  full   report 

 

PDO  --  The PDO     or   "Pacific Decadal Oscillation"     a long-lived   climate  pattern   that    exists over the northern Pacific Ocean.   The  PDO Phase  involves the location  and intensity   of   large pools of  warm and /or cold   Seas Surface   Temperature Anomalies  (SSTAs)   in the  central and   eastern areas of the  Northern Pacific.   Currently the  PDO is  in a  negative phase or Mode   as there is a large areas of   Colder than  Normal  SSTAs  in the  Eastern  Pacific.  This  strongly  supports  the Mean trough  Position  in the Jet Stream over the    eastern Pacific/ West coast.

 

 

NAO-- The NAO or North Atlantic Oscillation is one of the major configurations  in the   Jet stream patterns  over   the Northern Hemisphere atmosphere.  The NAO   configuration covers a   geographical   regions from eastern or northeastern Canada to Greenland and over towards Iceland / Ireland and it is particularly important in Winter months  when it exerts a strong control on the climate of the Northern Hemisphere. There are several manifestations of the NAO  but  the feature is   extremely  hard to predict. There are  no Known    methods for doing so but over the last several years  there are have been some  "preliminary"  findings that some  some promise in this matter.  Last Winter   the NAO turned  strongly  Negative in Mid January and  Locked into  place   which set up a   dramatically   different   second half of the Winter   2006-07
(Jan 15- March 15)

SE DROUGHT  -   This is an unusual   feature for the  Winter 2007-08. The  severe  and  large drought    that developed  over the  Deep  South in the  Summer of  2007  has  continued    thru the  Autumn.  The features mentioned  above   (-PDO  Moderate La Nina    -QBO  etc)    tend to  support  the  Mean trough  position in the Jet stream over the  West   coast/ Far eastern  Pacific  at least through the  1st half of the Winter.   This in turns means that downstream of the  trough   thee is going to be a  Ridge which  might be located anywhere between  the  Lower Plains and  Bermuda.  However with the   large drought over the SE CONUS   will    focus the   Ridge locking into Place  over the   SE.

 

SEASONAL TREND  -- So far the seasonal trend has supported a progressive pattern over the northern hemisphere and especially North America. There has been very little high latitude blocking and very little sustained -NAO over Greenland and / or northeast Canada. Most of the storm track activity over the past 60 days has been over the Plains... upper Mississippi Valley... and Great Lakes. There have been a few significant events for the East Coast but only one classic Nor'easter. The medium and extended range forecasts from the various global climate models in the week 2 timeframe had been unbelievably bad... which is to be expected given all the above-mentioned parameters.  

The month of November 2007 so far has turned out to be fairly cold over the eastern half of the CONUS which has led some to speculate that we might be headed for a colder pattern in the Consensus Forecast is indicating. However the data clearly shows that November's that featured moderate La Niña tended to feature a colder than normal November.

 

 

HOW  THIS  FORECAST   WAS  PREPARED

 

We have entered a new stage and weather forecasting over the last several years. While academically the interest has been in mesoscale features... the business concern as the climate continues to appear to become more unstable has been in 30-day and seasonal forecasting. There are several different techniques that meteorologists use in making a seasonal forecasts.  

 Among these various methods is the use all for "ANALOGS"... the SSTA-- sea surface temperature anomalies in the Pacific and Atlantic oceans... and  seasonal     indices and    patterns   (such as the  PDO in the  QBO     and  NAO  features)   new climate forecasting models.

THE USE OF ANALOGS


Many  (but not all)  forecasters use "Analogs"  to help make a seasonal or monthly forecast. In weather forecasting the use of analog is an attempt to understand   the  seasonal forecast period  based (in past) upon similarities between a particular set of parameters.   The idea is by searching   for similarities  with  other  years or seasons    it gives a forecaster some clues as  to how the   monthly or seasonal forecast  may  develop. .

For example one may consider the fact that most  US winters   during   strong  El Nino years bring warm and dry conditions to the Upper Plains   and Midwest   and  rather wet and cool conditions to the Deep South and changeable conditions in the Northeast.   Or a forecaster may look at say the past 6 months... 12 months... or 18 months worth of temperature  and  precipitation data over a certain section of the country and use those similarities to the current situation to assist them in making the monthly or seasonal forecast.

Done the correct way the Analog method has validity to it.  But the key thing to keep in mind is that when you are choosing a analog year you must choose one which matches the current set of conditions.      For example to simply assumed that all El Nino  events  produce   ONLY  one set of conditions in the winter months  is of course folly.    Some of the most severe winters in the last 100 years have been El Nino winters and likewise.... some of the most Mild winters in the last 100 years have also been El Nino winters.  

On the other hand some forecasters   hold  the view   that analogs  are   not very helpful since  weather  records are incomplete or not sufficient enough to be considered as   complete  data source.     For most locations temperature and precipitation data only extends back 100 or 130 years  and accurate Upper Air maps   only go back 70 years at best . That argument is   Valid.  Thus  ANY  seasonal forecast  using analogs  that is based on ONE   parameter is a   very risky  and has a high degrees of failure  built within the forecast.

One way of getting around this is to use several factors parameters and cross matching the analogs to look for common ground.

 

AUTUMN  PATTERN   2007 SO FAR...

 

While in important not to read too much into the autumn pattern it can be helpful in determining whether or not some of the expected conditions are in fact developing. As I have already stated I anticipate a Moderate La Nina event to last most of the Winter as well as a moderately strong negative phase of the PDO and a very strong easterly or negative QBO. What I have attempted to do in the autumn of 2007 is look to see if there are any clues in the autumn pattern which support the forecast hypothesis I have developed for the winter.

September and much of October featured abnormally warm conditions for much of the central and eastern CONUS. In late October and for most of November the pattern switched with most of eastern US seeing temperatures turning colder than normal for this area. However the  turn  towards a colder than normal LATE November  over the eastern third of the Conus is not unusual for moderate and strong  Nina events  and  there is  bias  to support  Cold nor is it uncommon for November is that feature -PDO events either.

However  WxRisk   sees something   far more important than  the  temperature  pattern shift  that  has occurred in the 2nd half of  DEC  over the  central and eastern CONUS.  That would be the    clear and  obvious  rise of  the  enhance  or stronger than Normal  Pacific Jet.  As  stated   above in the  CRITICAL  ASSUMPTIONS   section   WxRisk sees the  Much enhanced  Pacific  Jet as a serious  factor over all of   North America   for  the  Winter  of  20007-08.

 

THE  LA NINA  /  STATUS  FOR THIS WINTER ...

 

Although there is little doubt that the ENSO   event   (La Nina and  El Nino)   events are somewhat is over hyped... the fact of the matter is that ENSO   events   are major players  and MUST be considered in  any attempt to make a seasonal forecast.  ( The   warm   water  events ....popularly called    El Nino     can also be   referred  to   as    warm  ENSO....   while  the       cold water  events  ....  La Nina .... is    referred  to  as  cold   ENSO   events).

This map (fig 1)refers to   the    area of the world where ENSO   events   ( El Nino / la Nina)     occur.   There are two agencies  within the  US    that   have the  official  responsibility to   monitor  the  ENSO region -- CDC   ( climate    Diagnostic Center) and  CPC  (climate   Prediction center).   The  ENSO  region   consists  of   several sectors .... ENSO 1+2  (   1.2)    ENSO   3    ENSO  4   and   ENSO  3.4.   Officially  an El Nino or La Nina event is declared when the SSTA     (sea  surface temperature anomalies)    have reached a certain level for a 3 month time period   over the   ENSO   region known as    3.4 .

REGION 1 and 2 is situated right along the Peru coast just SOUTH of the Equatorial.
REGION 3 is the Red box area along the Equator.
REGION 4 is the Yellow area which extends along the Equator out past the Dateline.
REGION 3.4 is area shown by the THICK BLACK LINE .

 


figure 1


Also  you need to know that  there are several   sources   for   getting the  latest data   that  meteorologists  use  for  SSTAs   in the    various   ENSO    regions. 

Two sites provide  weekly  updates:   From CPC ...  http://www.cpc.ncep.noaa.gov/data/indices/wksst.for    and this site  from    the   Australians   http://www.bom.gov.au/climate/enso/indices.shtml  (I strongly prefer the  Aussie data)

While the  La Nina  of 2007   was  slow  and somewhat delayed in getting underway   it  has rapidly map up for lost  ground  in the   weeks of  OCT and NOV and  is now  as of Mid NOVEMBER  2007    clearly a Moderate  garden variety   La Nina. The real  question is whether the  La Nina will reach  STRONG    threshold criteria   during the Winter months  OR    will the Moderate la Nina   reach its  peak in  Mid  DECEMBER 2007  then  begin to decay  in the  2nd half of the winter ...in manner much like what  we  saw with the Moderate   El Nino Last winter .    A  decaying    La Nina   in  the   2nd  half  of  Winter of 2007-08   would  greatly increase the chances of  seeing a    2nd  half winter   much colder than the  CF is   currently  calling for.

 

WEAK  vs    MODERATE/ STRONG   LA NINA EVENTs

These next three images will clearly show differing impacts between a weak La NIna  vs   Moderate /  strong one with respect to temperatures.    As you can clearly see there is a  strong correlation between a weak La Nina event and colder than normal temperatures over much of the central CONUS  and  near Normal temps   for the Ohio Valley and Northeast. On the other hand  there is a much stronger   connection  are  between  Moderate and    Strong  La Nina  events and large areas of  Above and   Much Above  Normal temperatures  for the Lower Plains ...Deep South.... Midwest.... and  Middle Atlantic  states.  central...southern US.

 

EL NINO  TEMPS EL NINO  TEMPS LA NINA  TEMPS
OCT- NOV- DEC JAN FEB MAR DEC  JAN  FEB 

Looking at    ALL of  Moderate and   Strong  La Nina events  since  1950... and  we have to  include   Strong  La Nina event since  it is  possible   that this  developing  La Nina  will  reach   the lower  end of the  "STRONG"  La Nina   threshold at some  point this   Winter. This Image   shows Temperatures  from  the  Mean of all the  Moderate and  La Nina   events looks like  broken down by climate  divisions

    if  we  break   this   down by    3  Winter months  we   Get  these   temperature  anomalies  for  Moderate /  Strong  La Nina  events

DEC JAN FEB

 These  Images  clearly  show  the   hemispheric  pattern  at  500 MB  for   DJF. The  areas of  dark Blue and Purple  show   major  height anomalies In DEC    the signal is  pretty strong that   there is  sort of mean trough over the  eastern  Third of the   CONUS--  which can  be

 

DEC  500 MB
 HEIGHTS
JAN    500 MB
 HEIGHTS
FEB  500 MB
 HEIGHTS
 

 

 

 

  

 

 

This next  Link shows  the   large scale  500 MB   pattern   DEC  JAN  FEB  (DJF)  based on  WEAK   La Nina  events....   (click on image  for   full  view).  We  can see several  features over the  Northern Hemisphere.  Note the   Yellow and green  areas...over over  Greenland... over the   Eastern  Pacific  and  eastern Siberia. These areas show  positive    anomalies at 500 MB.    The   Dark Blue  areas   show  NEGATIVE  height  anomalies...   over   Scandinavia... the central  Atlantic  and  over  Japan.    They KEY  feature  is the Positive  anomalies  over  Greenland  and  the   negative  Height anomalies over   Scandinavia.  This is why      WEAK  la Nina  events  often lead to   seasonal or  colder than Normal  winters  over the  central and  Eastern  CONUS.  Greenand note the     se next three images will clearly show differing impacts between a weak La Nina  vs   Moderate /  strong one with respect to temperatures

 

 

 

 

 

 

   

 WEAK  FEB  LA NINA

      

 

These next two charts clearly show where the current El Nino event is with respect to other previous events since the 1950s. This first link shows you a chart comparing the current SSTA in ENSO region 3.4 the last 14 El Nino events and as you can see the current event is definitely in the weaker category  or  weaker  group of  all  14 El Niño events.
 

This next map shows you a more reasonable and closer look of the MEI of weak El Niño events since the early 1950s with respect to how this current event matches up. You can see that the closest overall match appears to be the 1963- 64 weak El Nino event...  but  all these events on this   chart  ....  were   significantly  colder  and snowier than normal  winters for Much   of the central and eastern CONUS.... except  for 1951-52
 

  It is important to keep in mind 2 salient points regarding this El Niño event. First we have never seen a El Niño event develop in the month of August. Not once as is ever happened. Second ... last winter... 2005-06 featured a weak La Nina event. If take a look at the history of the El Niño events in the Winter which have occurred after a weak La Nina the previous Winter we find a very significant fact in the database.

Which is this... Most of the El Nino events that have occurred after a WEAK La Nina the previous Winter has NOT reached Moderate El Nino criteria for more a than a few weeks. Let's take a look at this in a bit more detail. This chart shows is the CPC 3 month mean SSTA for the region of ENSO 3.4. I have highlighted in purple the five cases where we have seen a weak La Nina in a winter season that was then followed by SOME sort of El Nino event the very next Winter. They are



1957...1963...1968... 1986... 2001.



We can discard the 2001 event because after the weak La Nina died off the SSTA in ENSO  3.4  stayed flat the  Winter of 2001-02.

1957 began with a weak La Nina that quickly moved into weak El Nino in the SPRING then reached moderate levels of +1.2c and +1.5c in the 1957-58 winter. However the 1957-58 El Nino is not a great analog match for this season because that El Nino began in the Spring of 1957.

1963 is as close to a perfect match as one can possibly have. After the weak La Nina died off in the spring of 1963 SSTA remained a neutral until the Autumn then only rose to +1.0C in ENSO 3.4... which is exactly the pattern we are seeing what these current El Niño.

1968 ... is also a good match to the current event... the El Nino reached +1.3c briefly in January of 1969 then began to weaken.

1986... is also a decent match for the current event. However the cold water in ENSO 3.4 in the Jan and FEB of 1986 was not really strong enough to be officially declared a La Nina

KEY  POINT    THE  BEST   3 MATCHES    WHICH  MATCH  THE  CURRENT  LA NINO   IN THE  ENSO   3.4  REGION  are  1963.... 1968...1986...  then 1957   

 

ENSO FORECAST FROM   VARIOUS CLIMATE MODELS

This next table provides some information as to how strong the El Niño event names become during the winter. FIGURE 1 is a breakdown the18 Member CFS climate model used at CPC ... which is run every few days

As you can see there is a general consensus among these ensembles members of the CFS model that the warm SSTAs in ENSO region 3.4 will reach a peak of 1.25 to near +1.50 degrees sometime in middle or late January or perhaps very early February.... and then begin to the climate pretty steady pace
 

Figure 2 and three are the ENSO 3.4 region forecasts from the ECMWF centre in downtown Europe...
with Fig 2 based on September 1 and FIG 3 based on October 1. He may importance of these two images shows that he knew right of the European climate model shows a very sharp drop-off in the SSTA in ENSO 3.4 region in the 2nd half of the winter.

And lastly we can see figure #4 which is a collection of 19 various climate models that forecasters can consider regarding the ENSO region 3.4. Looking at this image we can see that almost all the models show a significant drop-off in the second half of the winter with the warm SSTAs in this region and only 1 model briefly reaches +1.5C with the vast majority of the data showing a borderline WEAK/ MODERATE event.
This next table actually is a breakdown of all those individual models that we see here and I have highlighted or summarized like these forecast models are showing... and began only a 5 of the 19 models show SSTA in ENSO 3.4 reaching and HOLDING Moderate level.

 

 
TABLE     1

CMB'S  ENSO    FORECAST

ECMWF   ENSO  3.4     Forecast IRI   CLIMATE   MODEL   FORECAST
19    FORECAST MODELS
REGION 3.4 SEPT   1 OCT  1 EARLY   OCT

1

2

3

 

4

 

   DETAILED   BREAK  DOWN OF  ALL 19 IRI CLIMATE MODELS  USED IN FIG 4

  Seasons (2006-2007)
Model OND NDJ DJF JFM FMA MAM AMJ MJJ JJA COMMENTS
Dynamical models            
NASA GMAO model 1.2 1.3 1.3 1.2 1.1 1 0.9 0.8 0.6 Moderate
NCEP Coupled Fcst Sys model 1 1.2 1.4 1.5 1.4 1.2 1 1   Moderate
Japan Met. Agency model 0.6 0.6 0.5 0.4 0.3         weak
Scripps Inst. HCM 0.9 0.9 0.9 0.8 0.7 0.5 0.3 0.2 0.1   weak
Lamont-Doherty model 0.9 1 1.1 1.1 1.1 1.1 1.1 1.1 1   weak/ Mod
POAMA (Austr) model 0.5 0.7 0.8 0.9 0.9 0.9 0.9     weak
ECMWF model 1.1 1.1 1.1             weak/ Mod
UKMO model 1.4 1.4 1.4             Moderate
SNU (Korea) model 0.9 0.9 0.9 0.9 0.8 0.8 0.7 0.6 0.5  weak
ESSIC Intermed. Coupled model 0.5 0.6 0.6 0.5 0.5 0.5 0.5 0.6 0.7 weak
ECHAM/MOM 1.2 1.3 1.3 1.2 0.9         Moderate   falls off to weak late  in winter
COLA ANOM 1.3 1.3 1.2 0.9 0.6 0.4 0.2 0.2 0.1 Moderate   falls off to weak late  in winter
Average, dynamical models 0.9 1 1 0.9 0.8 0.8 0.7 0.6 0.5 WEAK
Statistical models            
NCEP/CPC Markov model 0.9 1 1 0.9 0.8 0.7 0.6 0.6 0.5 weak
NOAA/CDC Linear Inverse 0.8 0.7 0.7 0.7 0.6 0.5 0.4 0.3 0.3 weak
NCEP/CPC Constructed Analog 0.8 0.7 0.6 0.4 0.3 0.3 0.3 0.4 0.4 weak
NCEP/CPC Can Cor Anal 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 weak
Landsea/Knaff CLIPER 1 0.9 0.9 0.8 0.7 0.7 0.6 0.5 0.4 weak
Univ. BC Neural Network 1.1 1.4 1.4 1.5 1.6 1.4 1.2 1 0.9 MODERATE
FSU Regression 1.2 1.2 1.2 1 0.8 0.5 0.3 0 -0.2 Moderate   falls off to weak late  in winter
TDC - UCLA 1.3 1.3 1.1 0.9 0.6 0.5 0.4 0.3 0.3 Moderate   falls off to weak late  in winter
Average, statistical models 0.9 1 0.9 0.8 0.7 0.6 0.6 0.5 0.4 WEAK
Average, all models 0.9 1 1 0.9 0.8 0.7 0.6 0.5 0.4 WEAK

 

MEI   INDEX


The  folks   over   at CDC     - Climate Diagnostic Center   have developed  a    More complete   way of   measuring  ENSO   events .... be it a   El Nino   or La Nina event. The  MEI   or  Multivariate ENSO Index (MEI)    measure       all  El Nino    and  La Nina    events  on six main observed variables over the tropical Pacific.    ( sea-level pressure...  zonal   surface winds...   meridian   surface winds....  sea surface temperature...   surface air temperature...  and total cloudiness as a fraction of the sky

   FULL DETAIL    and a better  overall image  of  ALL the   MEI    data since 1950   can be  seen here    http://www.cdc.noaa.gov/people/klaus.wolter/MEI/

However  for ease  of comprehension  I have    created this  table of  MEI  values   from  January to November  2006. what I am searching for here is NOT a  exact   numerical  Value match   but the overall trend . 

 

2007      MEI   VALUES  FROM JAN  TO   NOV  6   

 JAN FEB MARCH APRIL MAY JUNE JULY AUG SEPT OCT
-.382 -0.417 -0.554 -0.594 -.014 +.481 +.643 +.750 +0.892 +1.027

Note the MEI  values  were     moderately NEGATIVE   in the Winter and  Spring (hence the  weak La Nina)...  then rose to NEUTRAL   and  steadily  But  NOT rapidly   rose  into  weak El Nino    levels   in JULY AUG SEPT.   The OCT  2006   value  is  right on the  border between WEAK and  MODERATE  El Nino...

Here are the  4 analog  years that closet  match   with what we have  seen   with this  CURRENT  MEI .  Over on the far right columns  I have made  a few   comments   for your consideration  

1957

-.983

-0.426 +0.88 +.388 +.886 +.755 +0.958 +1.104 +1.138 +1.091 +1.111 +1.19   So-So... MEI  rose  to  above  +1.0 in AUG   1957
1963 -.748 -.893 -.684 -.784 -434 -.081 +.372 +.651 +.44 +892 +.934 +.703   PERFECT MATCH
1986 -0.304 -0.225 +0.040 -0.103 +.318 +.311 +.387 +0.713 +1.093 +1.012 +.856 +1.186 2ND  BEST ... ROSE TO  +1.012 in OCT 1986  matching the   OCT 2006  value
2002 -.111 -0.147 -0.81 +.414 +.882 +0.853 +0.567 +0.864 +0.806 +0.914 +.987 +1.151   Good  match   


KEY  POINT    THE  BEST   3 MATCHES   to  MEI    OF  2006 ....     1963   1986  and  2002


 

   THE   HURRICANE  OF  2007 --
DOES IT MEAN ANYTHING  FOR THE WINTER   OF  2007-08?

 
You know what's really interesting? Last year when we had that super active hurricane season there were an awful lot of private forecasters out there ranting and raving about how the 2005 Hurricane season was somehow connected atmospherically to what the upcoming Winter might hold for the eastern half of CONUS.   Now that we have had a sub active hurricane season... suddenly there are not a lot of people talking about the hurricane connection and what it might or might not mean for the winter.

Isn't that curious?


Since there is not a lot of speculation about what the 2006 hurricane season might mean for this    coming Winter across the CONUS... I won't spend a lot of time on this aspect of the forecast. However it one point I do want to make is that there is significant research out there which  shows  SOME    correlation  between Hurricane activity over the southeast US and what that means or implies for the following winter.

You see the problem was that last year these private forecasters that were banging  the drum about  Winter  of 2005-06  took that research and misused it. Instead of using the actual research which does lend some support to the idea that active hurricane season over the southeast US has implications for the overall pattern in the following winter... they took this data and asserted that ANY sort of above normal activity in the Gulf Mexico has implications for the overall Winter pattern. That of course is 100% BS...   However  IF the goal was to get an awful lot Media attention and get yourself on CNBC while Natural gas and Heating oil prices rise.... then that strategy was successful .

Again keeping in mind the original research... we have seen  some Hurricane seasons where there has been decent  a  cluster of  over the Southeast   CONUS and  the following Winters have been significant. The hurricane season of 1995 which featured  a lot of activity in the tropics    but saw  numerous   Tropical Cyclones constantly turned away from the East Coast ....because the mean trough position was located over the East Coast in the autumn of 1995. Likewise we sought awful lot of activity into Florida and the Southeast states in 2004 in the winter of 2004 --05 with reactive as well.

This year while we have not see a lot of activity...  they were three of the 9 named storms that developed in eastern Gulf OR off the FL coast that passes through a very close Florida and /or parallel the Southeast US coast... ALBERTO BERYL and ERNESTO. There also several Tropical Cyclones which were turned out to see in the central portions of Atlantic.  First let me show why this idea is crap and then why it was done.

 

THE  NAO   FACTOR


Again keeping in mind that it is my goal to convey information  without getting bogged down in Too much detail...
The NAO or North Atlantic Oscillation is one of the major modes of variability of the Northern Hemisphere atmosphere. It is particularly important in winter, when it exerts a strong control on the climate of the Northern Hemisphere. There are several manifestations of the NAO.  Basically without getting to technical  the NAO  a particular jet stream configuration which exists over the regions of the Northern Hemisphere from eastern or northeastern Canada to Greenland and over towards Iceland and Northwest Europe.

Sometimes you'll hear the phrase   'High Latitude blocking'   and if this is occurring over eastern Canada or Greenland for example     this phrase  might be referring to a negative phase of the NAO.

Arguably the most difficult aspect of any WINTER forecast for the central and eastern half of the CONUS is trying to predict or figure out what he and Io is going to be doing this winter... what percentage of the time will this critical feature be in the NEGATIVE phase ( colder and stormy pattern for the central and eastern US as well as se Canada) or POSITIVE PHASE (milder and less stormy).

 SOME  LINKS  FOR THOSE  WHO WISH TO KNOW MORE

http://www.cru.uea.ac.uk/~timo/projpages/nao_update.htmis

http://www.met.rdg.ac.uk/cag/NAO/index.htmlgas

This image is the latest sea surface temperature anomaly map for the entire world which comes from the Unisys web site... and it shows some very interesting things.

To begin there is a noticeable area of very warm SSTAs located east of the Newfoundland in the Northwest Atlantic which stretches up into the Davis Straits and east over towards the Northeast Atlantic. This pool of very warm water has been there since the Summer but back then this pool of very warm water was located significantly further south. In addition we can see some more temperatures that are actually below normal off the Southeast coast of the CONUS and sea surface temperatures are between Iceland and Greenland.

Research has shown that this sort of sea surface temperature anomaly configuration ( in the weather biz this is called the North Atlantic SSTA tripole) is supportive of a sustained negative phase of the NAO. This is not by any means a guarantee but there is some correlation between sea surface temperature configuration like the ones we currently have in the North Atlantic and fairly long intervals of the NAO staying in the negative.

In addition as I mentioned about with the drought pattern over the Plains states .... the location of the Ridge over the Plains supports the mean trough position over the East Coast which in turn does favor some sort of positive height anomaly over the Northwest Atlantic and /or Greenland.

If we look at the longer-term trend will see that the NAO  has been in the negative phase for the most part since late July early August with only a few brief intervals where the NAO went positive.
   Keep in mind there are a lot of government and private forecasts which attempt to predict me and we'll phase for either a portion of the winter or for the season as a whole. Most of their forecast have not as bad but wretchedly so in this may explain why so many of the last few went to forecast had been so bad across North America.

For example the British issue a "experimental" NAO forecast every Autumn for the following winter. As you can see from this chart... provided by the UKMO... they have been making these NAO forecasts for many years. The problem is that the British NAO seasonal forecast has really really wrong for many years. In fact I cannot recall the last time the British have gotten the NAO phase even remotely correct over the last 10 years.

 

Looking at the last several years of this chart since 2000... if the British went out of their way to intentionally forecast the WRONG phase of the NAO they could not do a better job!!! Of course that Is not what they are trying to do and they should be applauded for making an effort. However in my opinion by putting out NAO forecasts which well SUCK... a lot of private forecasters  refer  to the well-known British  NAO forecast as is some sort of reliable piece of data when as you can see from this chart the British NAO is absolutely worthless.
 

WXRISK VIEW:  While many  see the      SSTA    set  up for the  Atlantic   Ocean   as  NOT ideal for  sustained intervals of      the  negative  phase of the  NAO   I see  some promise.   Many forecasters assume that there can only be one particular manifestation of the negative phase of the NAO... which is called the Greenland Block. However sometimes you can get a
 -NAO manifestation that shows up as a blocking pattern over the Davis Straits... or  northeastern Canada  or   northern Québec.   Indeed we saw that several times during the months of September and October. And the strong pools of very warm SSTA in and around the Davis Straits and of the coast of southeastern Canada strongly supports the idea of a westward positioned blocking pattern developing over northern Québec or the Davis Straits from time to time this winter. I do not see a  " ideal"   SSTA configuration at this time although it would not take much to change the Atlantic SSTAs into a pattern that would favor sustained -NAO. 

 

 

PDO   INDEX

 

Over the  last   10 years there has been a significant amount of   research  done  on a   climate pattern   that   is   called the  PDO in the weather biz.  The PDO     or   "Pacific Decadal Oscillation"     a long-lived   climate  pattern   that    exists over the northern Pacific Ocean. 

The  PDO   involves the location  and intensity   of   large pools of  warm and /or cold   Seas Surface   Temperature anomalies  (SSTAs)   in the  central and   eastern areas of the  Northern Pacific.  Why is this important? Again     research  has  shown that large  areas  of   warm and cold  water   pools     called     SSTA  couplets    STRONGLY affect the    Jet stream pattern and the   positions of    Ridges and troughs  within   the Jet Stream over the   Pacific   and  western North America.

This is   diagram   shows    you    the Two phases  of the   PDO... the      BLUE  color    represents   very cold  SSTA...    the  Green    cool SSTA....   the    RED color  very  warm SSTA and the  Yellow   warm SSTA.

 

 

pdo_warm_cool.jpeg (194655 bytes)

    The map below explains     HOW  and  why the   PDO affects the pattern   across  North   America.  Click on the Maps to see the     Full  size.   As you can see when the PDO is in the Positive or WARM  phase... the warm sea surface temperature anomalies along the West Coast North America strongly supports a  ridge developing over the western portions of the continent and locking this Ridge in   place.    Of course if you have a Ridge over the West Coast then downstream you have to have a trough.... (for every action there is the equal opposite reaction)... which in this case is over the eastern third of the US. This pattern is known as the +PNA and it is the classic signature for a cold weather pattern. The arctic air masses from the Arctic regions and northern Canada follow the Jet stream down into this trough which results in sustained intervals of below row temperatures cold water. On the West Coast the Ridge of High-pressure means clear skies very little storminess and Above normal temperatures.

However the opposite is true what we had a negative or cold phase of the PDO. In this case the warm water is located out in the Central Pacific Ocean and cold water develops along the West Coast North America. This results in the jet stream developing a trough along the West coast... and of course downstream a Ridge develops over the eastern half the US. This sort of pattern results in a very cold and stormy West Coast with areas such as a Seattle and Portland saying snowstorms in the very strong cases out of the negative phase PDO... and the central and eastern US saying below normal precipitation and above mobile temperatures.

SCHEposPDO.jpg (132518 bytes) SCHEnegPDO.jpg (142521 bytes)

 

The correlation between the temperature patterns across North America and PDO phase is very strong and it's very hard to ignore.

The PDO  also  has some   impact  on El Nino  / La Nina  events.   While the PDO  and  ENSO  events   have similar climate   "fingerprints"...   they have very different behaviors in time.   For  example  a phase of the PDO  can persist for 20-to-30 years while typical ENSO events persisted for 6 to 18 months.    Within that  20-30 year  PDO cycle   one  phase   is   more  favored   than the other.     For  example  when the  PDO  is in the    "Negative  Phase"    most of the time  the PDO  will run in    the Negative pattern  with  just  a   few  instances of  PDO   developing a     Positive  Phase... and  vice  versa.    In  additions  the PDO directly affects  the  ability  of  the  El Nino or La Nina event  to reach    the STRONG    category.   When   the  PDO is in a negative phase    the   El Nino event trend to be weaker    while La Nina events  are stronger.    On the other  when  when the  PDO is in the Positive or  warm phase   the  El Nino events  tend to be longer lasting  and  stronger   while La Nina event s are weaker

 

     Again if we take a look at the latest SSTA  map    we  see large areas of cold water located off the Baja California coast and  SSTA that close to neutral or slightly below normal over much of the Northeast Pacific-- off the West coast of Canada -- and north of Hawaii.    In fact in the northern Pacific the only areas of really large bodies of warm water exist in  and around Japan.    The overall sea surface temperature pattern or configuration is clearly indicative of a negative phase PDO ( hereafter called a -PDO).     However it is not a strongly negative phase like we saw last year which means that it's possible during the middle or second half the winter the PDO phase could change... from negative to positive. In order for something like that to occur... they would have to be a significant increase in areas of warm either over the Central Pacific that moves eastward or developing over the Eastern Pacific near the North American coast. Began at this time there does not appear to be anything indicating that might be the case but because we are dealing with a weak -PDO phase such a change could occur in the second half of the winter.

Again keep in mind that -PDO means a constant stream of Pacific Energy bombarding the West Coast and it also restricts the ability of cold air pour southward from Western Central Canada into the central and eastern portions of the CONUS. However since this -PDO is a weak one ... there is a high probability that the Pacific Jet stream will split into two branches on the West Coast. This sort of split in the jet stream pattern is an indicator that forecasters look for that the pattern is about to become stormy.

 

 

 

    QBO   INDEX

http://www.atmos.ucla.edu/~cwhung/qbo.html
http://strat-www.met.fu-berlin.de/products/cdrom/html/section5.html
http://ugamp.nerc.ac.uk/hot/ajh/qbo.htm

The quasi-biennial oscillation (QBO) is  a Band of    High level  zonal winds  found   over the Equatorial  at very high  altitudes ( even above the  Jet Stream).  It is  a very well known   periodic oscillation in atmosphere.     The has been a lot of research done  over the last  10 years that shows the  QBO  has significant impact of overall climate patterns ...  as well as Winter  Weather patterns  as well as the    Hurricane  season.     The period of the  QBO  "oscillation"    is about  (a little over) two years.    The   QBO  has two  "phases"   with  occur within the    1 Oscillation  cycle-- the  Easterly  or  NEGATIVE  phase   and the   WESTERLY or Positive  phase.      Within the  meteorological    community   the  QBO  is    used   heavily by SOME  as a key ingredient  to figuring   out  what  the Winter  pattern across  North  America might be... while other forecasters  dont think its  all  that relevant.

In my opinion   However   much of  the  discussion   is mis-directed   towards    How and why  the   QBO is  important     For  example  it has been asserted that  during the Winter   season....the Eastern  half of the  US is often  cold and   snowier than  Normal  when  the  QBO is in   Westerly   or Positive phase   while  others  have asserted  that the   Easterly or Negative Phase  is better  for  colder and snowier   Eastern  US  winters.

This  LINK   has the   QBO  data  going back to  1948.   It is my position that the  QBO   index is  NOT a   indices  that    directly   relates to  the   overall pattern    per  se ...be it  Winter...  Spring...Summer  or   Autumn.    The reason  why I   think the  QBO   is  important  is that it   tell us   what the    Pacific  Jet    is  going to be  doing    over the  central and eastern Pacific.    Good   weather  forecasters    should   be willing to   tell you that if   you get the  West coast of North America    wrong ...    you get  EVERYTHING       else-- the  Rockies  to the Plains     to the Midwest   to the  Deep South and East coast    wrong as well.      Perhaps  this   explains   why   there are often so many   snow   and cold  forecasts for the eastern   US  out there  that are so often wrong  or  over hyped.

It is My contention  that   a    East or Negative Phase of the  QBO as we  go into the  Winter months   correlates  to a  more active and stronger    Pacific Jet   stream...  which means   more rains   and  storminess for the Pacific  NW and  West coast  and  a  Ridge over the    SE  or  East coast. 

 A  QBO    value that is    strongly  positive  as we  go into the  Winter months ...say   above  +10.0  or higher   almost always     implies   a  lack of cold air  build up in Canada and  a Milder winter for the CONUS . 

  A   QBO   value that is    near    zero as we  go into the  Winter months  --- say     from +5.0  to  -5.0      implies a   Pacific Jet  that is  weak   and   favorable  for   all sorts of   large scale  pattern shifts and changes  -- called pattern amplification and   de-amplification  (   lots of storms and  blocking patterns) . 

Here  are the   current    QBO  values   for   2005.

 

2007    QBO     VALUES  FROM JAN  TO   OCT   

JAN FEB MARCH APRIL MAY JUNE JULY AUG SEPT  OCT
-18.83 -11.24 -0.38 +5.00 +10.36 +11.47 +10.75 +9.10 +10.20 +10.86

 

The KEY point to consider is that IF the current QBO Phase stays strongly positive into the winter in any probabilities all saying significant cold air outbreaks or a colder than normal overall pattern would be significantly reduced. If on the other hand the QBO phase drops towards neutral then the overall pattern becomes much more promising for significant winter weather over much of the nation as well as the chances for more significant cold air outbreaks.

If you scan all the QB0  data and you look for QBO  events which were strongly negative... reached  NEUTRAL ...   then PEAKED ... and   dropped back to NEUTRAL ...  you can plot how long it takes for the positive phase of   the QBO  to run its course.   That cycle takes anywhere from 10 to 16 months.

1994-95 had a QBO that was at one strong negative-- minus 25.00 or lower. Once the QBO
reached Neutral with QBO took 12 months to reach the Peak Positive value then drop back to Neutral.


On 1996-7 the QBO was a strongly negative one -- that dropped to -25.00 or lower. Once the QBO reached Neutral... it took 11 months to reach its peak then back to Neutral.


1984-85 the QBO was a strongly negative one -- that dropped to -25.00 or lower. Once the QBO reached Neutral... it took 16 months to reach its peak then back to Neutral.

The current QBO phase became neutral in March 2006... it is now in its 9th month ( November 2006). It is probable that some point in the winter or specially the second half the winter the QBO  will rapidly breakdown with which neutral. This again leads support to the overall idea that the second half the winter was going to be significantly worse than the first portion of winter 2006 --07.


As for a QBO analog... let me emphasize that we are not looking for an exact match with respect to the numerical values per se but the overall QBO trend. What I am looking for is a analog to this particular pattern... a QBO that was very strongly negative ( -25.00 or lower) last winter... that became neutral by March 2006... that rose to +10 or higher in May 2006 and held close to +10 since then.
 

  JAN FEB MARCH APRIL MAY JUNE JULY AUG SEPT OCT NOV  DEC  
1957-58 -20.06 -17.24 -14.02 -9.27 -5.91 -2.30 +3.15 +7.07 +10.09 +11.69 +10.71 +8.30  NOT   a good match  Summer   1959 to Summer  2006
1957-58

-13.05

-11.58 -6.98 -2.01 +1.80 +3.21 +4.05 +6.30 +8.36 +10.46 +10.11 +7.35    NOT   a good match  Summer   1957 to Summer  2006
1966-67 -21.90 -17.14 -11.07 -2.33 +2.16 +5.42 +7.47 +7.63 +9.23 +11.00 +11.74 +13.26   too strong    going into winter  of 1966-67 when compared to   2006-07
1971-72 -10.67 -3.67 +0.91 +3.75 +6.77 +8.28 +8.8 +8.34 +8.95 +8.47 +8.47 +9.10  BEST ... note the  Plateau   of  Pos  value  between +8 and +9  all summer and  Autumn  1971 ... similar to  Summer Autumn 2006
1975-76 -16..0 -15.39 -13.04 -5.12 +1.18 +4.47 +7.41 +9.06 +10.25 +10.65 +11.27 +10.95 Good  match...  note the  Plateau   of  Pos  value  between +10 and +11  Autumn 1975

 

KEY  POINT    THE  BEST   3 MATCHES   to  QBO    OF  2006 ....   year 1971    1966   and 1975   

 

SNOW  COVER   NORTH AMERICA


Snow cover is one of those nebulous qualities that forecasters look at in the months of October & November in Canada. The Premise is that when you have early or heavy snow cover over a good portion of Canada there is a tendency to build colder and longer lasting arctic air masses which can then plunge into various portions all of the CONUS during the Winter months.


There is data which shows a very strong correlation especially east of the Mississippi River to mean temperatures during December January and February and snow cover in Canada. When the snow cover in OCT and NOV is above Normal Temperatures East of the Mississippi river tend to run Below or Much below normal.... and when snow cover in the months of October November is Below normal in Canada temperatures east of the Mississippi river tend to run milder than Normal.

That being said simply having early and/or heavy snow cover in the months of October and November over Canada does not necessarily mean that you are going to have a cold and/or Snowy Winter over the central and eastern US.   It just increases the chances that such a scenario COULD happen... the tendency to produce colder and longer lasting air masses is there. However if one were to look at the data from the Autumn of 1977 snow cover was below normal in Canada during the months of October November and yet that turned out to be one of the cold winters on record. On the other hand there was above normal snow cover in the months of October November 1978 in Canada and we had a very cold and stormy winter that followed in the lower 48 states.

The only thing can be said with any degree of certainty in my opinion regarding snow cover is that if you have October and November with below normal snow cover the odds are increased that you will have significantly LESS cold air outbreaks plunging into the CONUS. For example the super warm winter of 2001 --02 saw much below normal snow cover in October and November over Canada. The implication here is that when the cold air masses formed and moved south they rapidly modified as they came southward due to lack a snow cover in southern Canada during the heart of the 2001-02 winter.

To be certain we got off to a very weak start with snow cover over Canada in October 2006. The data does show that snow cover for Canada was below normal but we did see significant increases in the snow cover as the month came to a close. We can see that clearly here...

      and the differences in snow cover from the first week October when compared to the last days of October are quite impressive.  

    This increased snow cover continues through mid-November right up to the US Canada border.    The snow  cover   build  up  in Siberia is  Impressive -- Much above Normal there.



Now typically what happens with Moderate or strong El Niño pattern is that the large Upper Low develops over Alaska near the Bering Sea... and from this position the strong jet stream comes around the Upper Low and slams into Western Canada. This ends up destroying the snow cover in Western Canada as well as preventing any sort of cross Polar flow developing from Siberia into North America. This is just one of the ways (but a overlooked way) that a strong or moderate El Niño ends up affecting the overall pattern North America

However with a weak El Niño the entire pattern gets displaced. The vortex that in a strong / moderate El Niño is over the Bering Sea often gets displaced to the east in a weak El Niño... and is often found in the northeastern Gulf of Alaska  near the West Canada Coast. When this pattern occurs Western portions of Canada and the Pacific Northwest see a lot of precipitation... but much of it falls as snow since the very deep Vortex is located on the western Canadian Coast and that brings in some very cold air masses. In addition the weak El Niño position ends up increasing snow cover over much of Canada even while it provides a mild conditions for much of the CONUS.

Thus when the Jet stream decides to split into two branches the cold air is located very close to the US Canada border and the Arctic outbreaks can occur with a lot more frequency.


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