Area Forecast Discussion
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FXUS61 KGYX 240657
Area Forecast Discussion
National Weather Service Gray ME
257 AM EDT WED AUG 24 2016
High pressure will gradually sink to the south of New England
today allowing for warmer than normal temperatures on a
southwesterly wind. The warm weather will continue Thursday into
Friday when a cold front moves through. There will be a chance of
showers and possible thunderstorms as the front moves through,
otherwise, expect drier and slightly cooler conditions for the
weekend. Another frontal system may bring showers and
thunderstorms early next week.
.NEAR TERM /TODAY/...
High pressure at the surface this morning will gradually sink to
the south of New England today. This will allow a warm return flow
to develop and will likely result in highs a good 10 degrees above
normal today. Dewpoint values will increase as well but level off
only in the upper 50s to lower 60s which should keep it from
feeling all too uncomfortable.
.SHORT TERM /TONIGHT AND THURSDAY/...
A short wave trough will approach the region late tonight with
little fanfare. Deep layer moisture will be lacking and will only
be sufficient for a few clouds to move into western zones late
tonight or early Thursday morning. As that short wave trough moves
across the region on Thursday we expect a period of clouds but
little in the way of precipitation, perhaps a few spot showers or
thunderstorms late in the day across the mountains. Dewpoint
values Thursday should creep up a little bit, making it feel a
little more uncomfortable for some folks.
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
After the initial shortwave trough moves off to the east Thursday
afternoon, another will approach from the west Thursday night.
With a little more moisture and lift to work with, this one will
have a better chance of producing showers or thunderstorms by
Friday morning as a cold front sharpens and gets pushed eastward
with the advancing trough. Coverage does not look to be
widespread, but scattered showers with a chance of a thunderstorm
can be expected along and ahead of the front as it moves through
during the day Friday. Wind shear looks pretty good especially in
the low levels, so any stronger updrafts that can form could
rotate. Instability is the limiting factor with thunderstorms
Friday, though as has been proven again recently it does not take
a lot of instability to get a rogue spin up. Timing of the frontal
passage does not seem to favor a traditional diurnally triggered
severe weather event as the front should move into central and
eastern Maine by early afternoon.
Behind the front expect a brief period of stronger winds as
downsloping allows some of the stronger winds aloft to mix down.
Decided to go a little above guidance on winds in the afternoon.
Although we do have a cold front moving through, temperatures
Friday afternoon will be just as warm, if not warmer, than
Thursday due to the downsloping winds. Cooler temperatures won`t
really be felt until Saturday although forecast highs are still a
few degrees above normal. High pressure crosses the area on
Sunday, shifting into the western Atlantic.
Models are fairly consistent in bringing another shortwave trough
and associated frontal system through the area early next week,
though there are some timing differences. GFS is a little quicker
with the wave while the ECMWF is slower and wetter. Either way it
looks like a decent chance of showers or thunderstorms on Monday
especially in the north.
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Short Term...VFR conditions will prevail thru Thursday. Any river
valley fog should burn off early this morning. Winds to turn more
southerly during this afternoon and Thursday afternoon at coastal
Long Term...There will be a chance of showers and thunderstorms
early on Friday as a cold front moves through the area. This could
bring MVFR conditions at times, especially in the mountains. VFR
conditions dominate through the weekend although this time of year
early morning fog is almost always a possibility at Whitefield
Short Term...Conditions will remain below small craft thresholds
today through Thursday morning. However, a small craft advisory
may be required Thursday afternoon as southerly winds increase and
Long Term...Borderline advisory level wind gusts possible through
early Friday ahead of the cold front. Once the front moves through
there could be a brief period of gusty winds out of the northwest
but in general wind speeds should be diminishing. High pressure
over the Gulf of Maine brings light winds and calming seas through