Still Cold. Snow to Stay Offshore

Cold Arctic air remains in place across Southern New England and that will do two things.  1) It will be cold and 2) It will push the majority of a snowstorm out to sea.  I can't rule out a light dusting for some areas tonight and 1-3 on the Cape.  Regardless we are starting off cold again, albeit a bit "warmer" than yesterday.

5 AM 2 m Temps (image wxbell)

Here are the forecast wind chills from the RAP for 7 AM

10z RAP 2 m Windchill valid 7 am EST (image wxbell)

A windchill advisory is in effect until 10 AM for much of Massachusetts and parts of RI and CT.

NWS Taunton Windchill advisory til 10 AM

Here is the surface chart for this morning.  I've circled a pair of low pressure systems which is combine energy in the Ohio Valley and then reform a new center on the Coastal Plain.  I've drawn the wind direction around the high pressure in the Northeast, helping to suppress any waves from jumping up the coast.

HPC surface

So what to expect and how much?  Here is what last night's EURO run printed out in precipitation amounts

00z EURO 2 m T and precip (image wxbell)

It will be cold so can we saturate the atmosphere?  At 700 mb there is some lift and Relative Humidity is running over 90 percent

00z NAM 700 mb RH, VV valid Fri 10 PM (image wxbell)

At 850 mb however the ideal snow growth zone is too far to the south.  

00z NAM 850 Temps, heights valid 10 PM EST (image wxbell)

Here is the HPC probability for 1 inch of snow tonight

Day 1 Snow Probs 1 inch (HPC)

I won't make a map but I expect a dusting to 2 inches South of the Pike.  Saturday will be cold like the past few days.  Temperatures will begin to moderate during the overnights and during the day.  By that I mean expect highs in the mid 20's and lows in the upper single digits to low teens.  Temps will try to rise on Monday and there looks to be some precip.  Right now I think an icing event is likely.  A ridge isn't going to just push this cold dense Arctic air out, not without a fight.  Cold will linger in the lower levels.  

Here is last nights GFS with 850 temps shown

00z GFS 850 temps 1 am Tuesday

The 1000-850 average however looks like this

00z GFS 1000-850 thickness Tuesday 1 am (image wxbell)

Also notice the high pressure stuck up in Canada.  Looks like ice and I hope I am wrong.  There is nothing worse than ice.  Have a good day.