Rain, Wintry Mix Will Arrive This Evening

There are some sprinkles around Southern New England this morning but the main action is still to our west.  Rain will begin to overspread the region mid to late afternoon.  South of the Pike and Inside 495 it will begin as some rain.  Northern Worcester, Franklin and Hampshire counties will see some snow/freezing rain/mix to start the event.  Most of the interior will go over to mix/sleet briefly tonight but it goes back to rain by 4 AM.  This is generally a minor event with *Winter Weather Advisories* posted.

NWS Boston AM Headlines

General Overview
Here is the regional radar round up as of 6 AM

NWS Northeast Regional Radar Loop 

Low pressure moving slowing out of the Great Lakes into the Northeast will force a secondary low to develop this evening.  Here is the surface analysis as of 4 AM.

WPC Surface Analysis 4 AM 

The surface low is being driven by a pair of upper level disturbances.  The trailing disturbance will eventually take over the steering of our precipitation.  A new surface low will eventually develop near the Jersey Shore.

06z NAM 500 mb vort, height Tues 4 AM (image NCEP)

There is high pressure to our north this morning and it is cold in Western and Northern New England.  For Southern New England it is 35 in Boston, 32 in Worcester, 32 in Providence but 28 in Hyannis, 22 in Springfield, 27 in Lawrence.  There is a wide variety in temps which makes the forecast a bit more challenging.

New England/New York 2 m temps 5 am (image Weatherbell)

Short Term Forecast
Here is how the surface is expected to evolve between 1 PM this afternoon and 7 AM Wednesday morning.  This is not a swift mover.

Click to enlarge

Precipitation begins as rain around 4 PM.  Change over to snow/sleet/ice in Southern Worcester County is not until after the PM commute.  Leaving Worcester to head south may be a bit slick however.   The precipitation is pretty much down by 4-5 AM Wed.

09z HRRR 1, 5, 10 PM sim radar and 06z NAM hires 1 AM Wed sim radar (image Weatherbell) CLICK to enlarge

Temperatures max in the mid to upper 30's today and only drop into the low 30's tonight.  Some left over showers are likely Wednesday as this system takes its sweet time clearing out.  I'll update as needed tonight.

NWS Boston Snowcast 

-Zack Green