Checking various "forecasts" from NOAA, to WCVB, to weather.com etc etc shows a total mix of guesses at this point.
Could be rain changing to snow, could be heavy wet snow, could be rain, could be cloudy no rain or snow -- in other words, they really are totally clueless at this point.
I like this discussion best though.....
http://forecast.weather.gov/product...&format=CI&version=1&glossary=1&highlight=off
SUNDAY...
EXERCISING CAUTION AS THERE IS NO CERTAINTY AS TO OUTCOMES. SEVERAL
POINTS CAN BE MADE THAT EXACERBATE THE COMPLEXITY OF THE FORECAST.
ONE: ATTRIBUTING N- AND S-STREAM IMPULSES REMAIN POORLY SAMPLED BY
UPPER-AIR OBSERVATIONS. TWO: EC/
GFS/CANADIAN
ENSEMBLE MEMBERS AND
DETERMINISTIC FORECASTS VARY WIDELY IN ALL CATEGORIES INCLUDING THE
STRENGTH...TRACK...AND TIMING OF A POTENTIAL COASTAL LOW OVER THE
GULF OF MAINE. THREE: THE WIDE VARIATION MAY BE IN PART DUE TO THE
LACK OF CLARITY AS TO WHETHER N- AND S-STREAM IMPULSES PHASE /MOST
SEEMINGLY
DOWNSTREAM/ OR REMAIN SEPARATE. TO THAT REGARD IT IS
POSSIBLE THAT THE BULK OF ENERGY BETWEEN THE TWO SYSTEMS IS SHIFTED
DOWNSTREAM TO THE
LEE OF THE HIGH TERRAIN ACROSS REGIONS OF BETTER
BAROCLINICITY /OFFSHORE/ RESULTING IN MOST OF THE ACTIVITY JUMPING
OVER OUR REGION LEAVING US FOR THE MOST PART QUIET AND DRY.
HOWEVER...RECOGNIZING THE PROFICIENCY AS WHICH FORECAST MODELS HAVE
PERFORMED 7-DAYS OUT...THE OVERALL
MEAN SIGNAL OF WEATHER OUTCOMES
CAN NOT BE IGNORED JUST BASED ON THE
ENSEMBLES. WPC HAS ACCEPTED THE
TREND OF A MORE AMPLIFIED SIGNAL BASED ON SUPPORTIVE 14.0Z GUIDANCE.
ECHOING WPC SENTIMENTS...WITH PERSONAL PREFERENCE GIVEN TO THE 14.0Z
AND 13.12Z EC/EC-ENS AND CMC/CMC-ENS RESPECTIVELY...SOME CONCERN AS
TO MAGNITUDE OF SE-
FLOW OUT OF THE HUDSON BAY AREA ANTICIPATED WITH
THE DEVELOPMENT AND INTENSIFYING COASTAL LOW INTO SE CANADA...AS
WELL AS HOW EFFICIENTLY
MOISTURE CAN BE DRAWN N OFF THE NW-ATLANTIC.
THEREFORE...WILL KEEP WITH CHANCE
POPS FOR THE FORECAST PERIOD WITH
THE THREAT OF RAIN ACROSS MUCH OF THE REGION SUBSEQUENT WITH THE
DRAW OF WARMER AIR N...WITH THE POSSIBILITY THAT SHOULD A STRONGLY
AMPLIFIED COASTAL LOW TAKE SHAPE OVER THE GULF OF MAINE...THAT THE
SE-DRAW OF COLDER AIR FROM THE HUDSON BAY REGION ALLOW FOR THE MIX-
TO CHANGE-OVER TO SNOW ALONG THE W-PERIPHERY OF THE ANTICIPATED
PRECIPITATION SHIELD. HEAVY RAIN / SNOW ACCUMULATION POTENTIAL AS
WELL AS WIND GUSTS ALL SPECULATIVE PENDING BETTER CERTAINTY AS TO STRENGTH OF THE SYSTEM"