Area Forecast Discussion
Issued by NWS Portland, ME
FXUS61 KGYX 221949
Area Forecast Discussion
National Weather Service Gray ME
249 PM EST Wed Feb 22 2017
Low pressure moving east through southern Canada will drag the
boundary back north as a warm front...leading to a mild night
tonight and warmer day Thursday. Highs will climb into the 50s
to near 60 across New Hampshire...with 40s to near 50 over
western Maine. A weak shallow cold front will try and push south
across the area by Thursday evening. But, once again the
boundary lifts north as a warm front Friday night. A strong cold
front and more widespread showers moves across the region
Saturday night followed by a drier and colder air mass for
.NEAR TERM /THROUGH TONIGHT/...
The evening will start out mostly clear as per Satellite imagery
suggests. By later tonight patchy valley fog is expected to
develop due to the residual low level moisture from the snowmelt
this afternoon combined with calm winds. Tonights overnight
lows will be mild with temperatures in the upper 20s to lower
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Thursday models show a mild southwest flow to develop with h85
temps aloft to reach +6 to +8C. This flow should allow temps to
reach near 50 in the mountains and southern Maine and could
reach near 60 over southern NH. A weak cold front tries to push
south across the area but weakens and then washes out as it
moves through the area by Thu evening. A few showers are
possible in the mountains with its passage Thursday afternoon
and evening but it should remain dry elsewhere. Patchy fog may
once again form overnight due to the snowmelt. Temps will once
again be mild with overnight lows ranging from near 30 in the
mountains and mid 30s to lower 40s elsewhere.
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Models are in fairly good agreement in the long term. A frontal
boundary will stall just south of the region Friday...then start
to push back through the area as a warm front Friday night as
low pressure moves northeast through southern Quebec. This will
lead to a rather warm day Saturday. As the low continues
northeast Saturday night the trailing cold front will cross the
region with rain showers which will change to snow showers in
the mountains overnight Saturday night as colder air pushes
into the region. At this time it appears that the moist system
moving northeast in Atlantic will not phase with the northern
frontal system until after it passes through the region. The
models continue to show the heaviest showers with the frontal
passage in the mountains...and combined with the snowmelt caused
by the warm temperatures may produce some ice movement on the
Drier air moves into the area Sunday but with a northwest flow
there will be a persistent threat of snow showers in the
mountains through Monday. Weak systems pass north and south of
the region late Monday and Tuesday with the next threat of
significant precipitation for the area on Wednesday.
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Short Term...VFR conditions tonight will become locally IFR in
developing areas of valley fog aft 06z. The valley fog with IFR
conditions is expected to burn off by 14z but with some MVFR
cigs remaining. VFR conditions will prevail elsewhere.
Long Term...MVFR to IFR conditions possible in showers and fog
Friday night into Saturday night. MVFR to IFR conditions
will persist in the mountains in scattered snow showers through
Short Term...A warm front moves north across the waters tonight.
A developing southwest flow Thu will begin to build seas to
near 5 ft by evening and continue Thu night. SCA`s may be
needed for Thu night due to seas over the outer waters.
Long Term...SCAs likely outer waters late Saturday through
Monday and again on Wednesday.