Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Gray ME
946 PM EST Friday Nov 28 2014
high pressure will crest overhead tonight. A warm front will move
north Saturday and pass through northern New England Sunday
morning. A cold front will move through the region early Monday
morning. High pressure will build in Monday and crest overhead
Tuesday. A cold front will approach Wednesday.
Near term /until 6 am Saturday morning/...
935 PM update: skies have become mostly clear and winds light.
Temperatures falling rather quickly as forecast. Only minor tweaks to temperatures
forecast at this time based on latest observation data. No other changes.
expect some snow showers early this evening especially in the
mountains but skies should clear later leading to a very cold
night across the forecast area as high pressure crests overhead.
Winds will be light and skies should clear. The NAM is the warmest
model tonight with the GFS being just a bit colder than the European model (ecmwf).
I have used a blend of the NAM and European model (ecmwf)/GFS for mins tonight.
Lows will drop into the single digits most everywhere with some
lower teens close to the coast.
Short term /6 am Saturday morning through Saturday night/...
a warm front will be approaching the forecast area Saturday.
Expect clear skies Saturday morning with increasing clouds
Saturday afternoon. Again the models differ with the high
temperature forecast. NAM is the warmest with the operational GFS
being the coldest by far. The parallel GFS is warmer than the
operational GFS and very close to the 00z European model (ecmwf). I used the
parallel GFS and European model (ecmwf) to populate maximum temperatures for Saturday.
The warm front will increase probability of precipitation Saturday night with snow showers
possible. Temperatures will be cold but not nearly as bad as tonight with
lows in the teens and lower 20s. Temperatures may become steady or even
rise a bit before dawn on Sunday. I used a blend of models for
Long term /Sunday through Friday/...
overall the progressive pattern continues with several swings in
temperatures but not much precipitation over the next several
days. Confidence decreases significantly for middle week.
Sunday will see temperatures rise through the day as warm air
advection sets in. Surface high pressure moves off to the east and
winds become southwesterly. With the increase in temperatures
comes an increase in moisture and skies will be mostly cloudy.
Classic warm frontal isentropic uplift will result in scattered
showers. A cold front moves through the region early Monday
morning bringing a few scattered showers before temperature begin
to drop through the day on Monday. By Monday night northwesterly
flow and cold air advection will set in.
Tuesday will see a cold high pressure system build into the
region. Initially the string pressure gradient will result in
gusty winds Tuesday morning... but winds will decrease as the high
crests over the region on Tuesday night. Temperatures will be in
the teens to 20s through Monday night and into Wednesday.
Forecast confidence decreases Wednesday as the high pressure
system pulls out to the northwest. Both the GFS and the European model (ecmwf) try
to put a trough through the region on Wednesday... bringing
precipitation. However ensemble guidance shows a big spread in the
location of the trough, leading to low confidence in the timing
and type of any precipitation. Have opted to run with a blend of
guidance as this is still day 6, but certainly trending towards
another wide spread precipitation event for middle week.
Aviation /03z Saturday through Wednesday/...
short term...expect some early MVFR/IFR in the mountains due to
snow showers this evening otherwise VFR conditions through
Saturday. MVFR ceilings likely to move in late Saturday night.
Chance MVFR visibility is snow showers.
Long term... warm air advection will drop ceilings to MVFR on
Sunday. Monday a cold front will keep snow showers at hie and leb
but elsewhere return to VFR with gusty northwesterly winds.
short term...no flags on the waters. Winds and seas will start to
increase Saturday night as winds turn to the southwest.
Long term... Sunday winds will increase to near Small Craft Advisory on the outer
waters in southwesterly flow.... after the cold front moves
through on Monday winds will shift northwesterly and approach gale