Brrr...Frosty Start to the Day

Light winds, clear skies and a Canadian air mass have combined for the coldest temperatures since spring time across Southern New England.  Frost and freeze advisories were issued last night and will be in place until 9 AM.  The chilly start will give way to afternoon highs in the low 60's.  Temperatures will drop to the upper 30's/low 40's again tonight before rising into the mid to upper 60's on Wednesday.  Some clouds and light rain are possible Wednesday night into Thursday as a weak cold front passes the region.

General Overview
Here are the frost/freeze advisories

NWS Boston Headlines Tuesday 548 AM

These headlines are needed thanks to temperatures region wide in the low to mid 30's (away from the urban and coastal regions).  Although winds are light the direction is out of the north.  So the cape is getting wind off the water which is still near 60 F.

RTMA 2 m max temps 4 AM Tuesday (image Weatherbell)

The surface chart shows high pressure in control over the northeast.  Air rotates clockwise around high pressure which is why the source region is Canada.  The Bruins open up Thursday so a Canadian air mass seems appropriate (especially now that the Sox are done).

WPC Surface Analysis Tuesday 2 AM 

We see a developing cold front across the plains ready to move into the Great Lakes states.  This shows up well on the satellite image this morning.    Note the strong high in Canadian Rockies driving this front into the US.

NOAA GOES_East Rainbow IR satellite (image NCEP/NOAA/NWS)

The impressive storm in the lower right corner of the satellite is Tropical Storm Nicole (soon to be Hurricane Nicole).  She appears to be on a collision course with Bermuda.  The high pressure will protect the northeast from Nicole as he will be forced to the northeast,

The Forecast
Today's high temps which are pretty close to average (+/- 2 in general)

NWS Max temps Tuesday (image Weatherbell)

It is slightly warmer tonight when compared to this morning but some areas will certainly want to keep the heat on especially north and west of the Pike.  Some spots south of the Pike in interior SE MA will also be cold tomorrow AM.

NWS minimum temps Tuesday PM-Wednesday AM (image Weatherbell)

Again temperatures are a few degrees warmer tomorrow.High pressure will slide offshore and our winds will flip around to the south.

NWS maximum temps Wednesday (image Weatherbell)

Thursday will also be mild for mid October as the Great Lakes cold front swings through the region.  Here is the frontal position on Wednesday night at 8 PM.

WPC Surface forecast Wednesday 8 PM

I hope we can squeeze out a few showers from this front but it looks like it will weaken as it approaches the east coast.  The air mass behind the front is also chilly for this weekend.

Have a great day
-Zack Green