Situation météo possible pour lundi (Québec jusquau État-uni

[hurricanes hunter]

Fast-Moving Storm Targets An Area From High Plains Into The St. Lawrence

Valley For Heavy Snow, Ice, And Wind; Blast Of Arctic Air Will Be Concentrated

Over Great Lakes And Northeast Next Week, While Western States May Be Hit With

Wind Damage And Flooding From Series Of Pacific Ocean Storms

 

 

(Disclaimer And Copyright Statements At End Of The Discussion)

 

 

 

WEATHER SUMMARY THROUGH NEXT 72 HOURS

 

 

The center of low pressure now organizing over the TX/OK Panhandle Region

represents a fairly major winter weather event from the Front Range into the

Great Lakes and St. Lawrence Valley. Specifically, the Chicago IL/Milwaukee WI

corridor could see significant snowfall, as could Montreal and Quebec City in QC.

One word of caution; as noted in the previous edition of WEATHERAmerica, the

snow to ice conversion line almost certainly will pass through the Windy City

itself. So those living in southern Cook County may only get into 2-4 inch

falls of the white stuff (after a mixture of sleet, snow, and freezing rain),

while some enhancement from Lake Michigan could jack up accumulations into the

10" category in places such as Kenosha WI and Waukegan IL.

Of course this system is critical in that the huge reservoir of bitter cold

values over Canada will be drawn into the northern tier states behind the

deepening cyclone. Only the Upper Midwest; Great Lakes; and New England will see

the full brunt of the cAk dome, probably over the course of the next 4 to 5

days. While it is true that temperatures should fall substantially (perhaps into

the 5 to 10 deg F below normal range) from the Great Plains into Dixie, the

relatively unamplified look of the 500MB longwave pattern does not favor extreme

thermal variations below 40 N Latitude. Since there is no NAO-styled blocking,

and the Omega signature in W AK is retrogressive, this is not a locked-in,

long-lived cold spell.

That said, the current advance of very mild, moist air from the Gulf of

Mexico will be ended over the Old South and East Coast by Monday. Some strong

thunderstorms and locally heavy rainfall should occur from the Ozark Plateau into

the Ohio Valley precedent to the passage of the cAk front, while a temporary

intrusion of cPk readings into the interior Northeast could make for icy travel

and brief (moderate) overrunning snows from NY State into central and northern

New England. I would not be surprised to see portions of Lower MI....SE

ONT....and QC involved in blizzard conditions by later tomorrow into Day 3.

No fooling, the Intermountain Region is plenty cold! A weak shortwave could

trigger another round of heavy snowfall even at lower elevations in N

CA....OR....WA....ID today. Brief clearing on Sunday may give way to another

approaching mPk front and wave after 60 hours, with the Pacific Northwest at risk for

excessive precipitation and strong winds. There is some good news in the winter

wonderland that is the West, however. A weak PNA ridge axis will set up along

the Continental Divide as we head into the medium range, which may allow for

some warming and drying in the mudslide-ravaged, chilled southwestern U.S.

Short-Range Numerical Weather Prediction Models

(red dot indicates preferred model)

______________________________

http://www.weathermatrix.net/archive/wxame...rica/0000.shtml

[Wilbo78]

Ouais, j'ai lu ça samedi matin... cette discussion date déjà de 24 heures... les modèles indiquent depuis que le gros passera au sud du territoire du Québec quoique Larry Cosgrove (celui qui écrit cette "NewsLetter") a tendance à ne pas toujours se fier à 100% aux modèles mais plutôt selon son propre jugement (ce qui peut être bien!)... nous verrons bien ce qui arrivera!

 

 

 

Envoyer mon message (04-01-04 07:09)

[beachcp31]

Finalement, on aura 5 à 10 cm, et même peut-être seulement 5-7 cm selon les derniers modèles... petite chute de neige! Dommage...