Wednesday, February 20, 2013

Blustery Wind/Cold Wed-Thur, Snow This Weekend

A storm system that brought beneficial rain is exiting off the coast this morning.  I say beneficial because it helped to eat some of this snow pack.  There is snow in the medium and long range forecast.  In the short term high pressure builds holding temperatures below average and a tight pressure gradient will allow for windy conditions over the next several days.

Wednesday/Current Conditions
It is still in the low 40's in coastal regions of Eastern MA/RI/ME.  Generally lower to mid 30's elsewhere (Berkshires I see you in the low 20')
4 am 2 m Temp Analysis (Image weatherbell)
Here is the surface chart
HPC Surface Analysis 520 AM EST
That is a 1042 high centered over the Manitoba/Ontario border.  Over the northeast pressures are running around 1000 mb as the system that brought some heavy rain last night is still in the vicinity.  This gradient is the reason for the gusty winds.  Temps today will max in the upper 20's for many west of 495, low 30's east
00z EURO Max 2 m Afternoon temps (image weatherbell)
By 7 PM this evening wind chills will drop into the single digits and likely close to zero overnight
09z RAP Windchill valid 7 PM (image weatherbell)
Thursday
Much of the same for Thursday.  The high pressure system doesn't move much or weaken.  Models are in good agreement and I like the HPC forecast map

HPC 48 hour forecast valid Thursday 7 PM
One can see active weather moving out of Texas into the Plains.  They really need the moisture there as they are in exceptional drought.  None the less temperatures will likely be slightly cooler on Thursday as the high makes a subtle shift into Ontario 
00z EURO T 2m Thursday Afternoon (image weatherbell)
Friday
The large storm in the plains will move northeast towards the Great Lakes.  It will run into the strong high and begin to weaken.  However it will begin to send some warmer air into the Northeast so Friday looks to be the best of the rest.  Temperatures across the region will reach the low 40's with light winds.  The February sun will feel nice.

Saturday-Sunday
The Plains/Midwest storm will push as far to the north and east as it can but it will be forced to weaken due to upstream blocking.  This will force a secondary development off the east coast.  
HPC forecast Saturday Morning
24 hours later I am expecting a set up similar to this
HPC forecast Sunday Morning
The question is amounts, how much mixing etc.  Along the coast I do expect precipitation type issues as there is a not a classic high pressure over Montreal draining cold air into New England.  The mix shouldn't make it to far past 95 in Massachusetts however and areas from the Boston-Prov-Hartford line north should see mostly snow and heavy at that.  The rain snow line will be critical in this storm because the heaviest snow will be just to the west/north (depending on orientation).  General timing is Saturday Afternoon into late Sunday morning.  
First Outlook
I'm not going to be specific with totals yet, but expect a plow able snowfall.  Hey Ox take the over.  This looks to be a heavy wet snow, not the powder we have seen lately.  That keeps amounts down but causes many more problems.











1 comment:

  1. While agree about the weekend potential.......I would be a little worried about a mix further into Connecticut. Original low tracks pretty far in the Great Lakes. And there is a pretty good push of warm air from the Southwest before the Secondary really gets going. Of course this could all change and we could see a repeat of a couple weekends ago.

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