November temps running 6-degrees behind a year ago; Tuesday's nippy 41-degree high no match for 70 last November

A chill continues in the air as Wednesday dawns. But the tight grip cold air has maintained over Chicago’s weather is to loosen over the coming week, albeit slowly—and we stress the word “slowly”.

 

More than 70 per cent of this November’s days have produced deficits and the month is running more than 6-degrees behind the same period a year ago.

 

Nowhere may the warming occur more slowly later this week and over the weekend than in areas adjoining the Lake Michigan shoreline, thanks to the easterly winds predicted to blow off waters averaging just under 48-degrees into Monday. This should limit weekend highs to the low 50s on area beaches and in shoreline locations.

Tuesday produced only the fifth 100 per cent sunny day of the meteorological fall season to date

 

Tuesday’s gloriously sunny skies delivered 100 per cent of the day’s possible sunshine. Veteran Chicago observer Frank Wachowski reports that it was only the 5th day of the meteorological autumn season (which began Sept. 1) to receive its full allotment of sun.

 

Both coasts to log big precip tallies in storms over the coming week while the already dry U.S. mid-section remains largely precipitation-free

 

 

The  period through this weekend will see heavy precipitation tallies on both coasts, while the nation’s mid-section remains dry.

 

Local 6″+ rain totals are forecast for an area northwest of Seattle in the Pacific Northwest over the  next 7 days while the movement of a western Atlantic storm, predicted by a number of computer models, to parallel the Mid-Atlantic and Northeast coasts, may dictate the amount of moisture to which coastal areas there are exposed.

 

A number of the best-performing models predict a mammoth new storm over the western Atlantic—but the handling of this storm varies from next Monday forward, suggesting forecast uncertainty still exists

 

Even the thought of another nor-easter—-potentially the third in as many weeks—is abhorrent, given the decimated state of so many stretches of the East Coast. Yet, our best performing computer forecast models on Hurricane Sandy and the nor-easter which followed last week, are on record developing ominous scenarios for the Mid-Atlantic and Northeast in the coming week.

 

The forecast model run by the U.S. Navy, known as the “NOGAPS”, as well as Environment Canada’s “GEM” model and the European Center’s operational “ECMWF” model, each develop a mammoth, wind and heavy precipitation system in contact with coastal areas. The National Weather Service’s “GFS” model keeps storm development well offshore, yet suggests strong northeast winds may still come in contact with the coastline later this weekend.

 

The European global forecast model, which  performed particularly well on the last two storms, takes the nor-easter ashore in New England as does the Tuesday run of the Canadian GEM model.

 

That there is a level of agreement among models which did well with the earlier storms, makes this a situation which will have to be monitored closely in the days ahead.

 

North Atlantic blocking pattern could prevent storm from heading away from coast as some forecast scenarios suggest

 

A sprawling dome of warmth aloft over the North Atlantic—present and a key player in the storms of the past two weeks—could play a role in forcing this latest storm close enough to the coastline to be a real trouble-maker.