Area Forecast Discussion
Issued by NWS Portland, ME-- Highlight Changed Discussion --
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FXUS61 KGYX 212205
Area Forecast Discussion
National Weather Service Gray ME
605 PM EDT Wed Sep 21 2016
High pressure will be centered over the region tonight and move
off the coast Thursday. A strong cold front will be slowly
drifting south into northern areas late Thursday night and then
into southern areas Friday. Scattered showers are expected along
and ahead of this cold front. Dry conditions and the coolest air
of the season are expected over the weekend and through much of
next week as a large Canadian high pressure builds south across
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
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Have updated the forecast based on current observations and latest
set of mesoscale models. Mainly clear skies continue across the
region after a day with above normal temperatures once again for
Patchy fog will develop once again tonight, however expect the
moisture to be less plentiful as it has over the past two nights,
especially along the coast. May need to adjust mins down slightly
with current dew points running in the 40s in many areas early
High pressure will be centered over the region
tonight with generally clear skies at the onset. But, high clouds
should spread over the area later tonight well out in advance of
the approaching system from the Great Lakes. After midnight river
valley fog once again expected to develop. Overnight lows will be
generally in the 50s as per guidance.
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.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
An approaching Canadian short with help drag south bottled up cool
Canadian air well to the north of the area. As this short wave
approaches increasing clouds are expected and then scattered
showers to develop in the mountains later in the day. Another mild
day is expected with a light southwest flow in advance of the
Thursday night the cold front gets pushed south into northern
areas. More numerous showers are expected along and ahead of this
front across the north and scattered showers should reach
southern areas toward morning. QPF amounts should be
light..generally a quarter inch or less since there will be a
limited moisture source associated with the Canadian system.
Expecting a rather mild night due to cloud cover and mixing ahead
of the front.
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Models are in good agreement today. The cold front gradually
slips southward during the Friday and Friday night. Showers will
be likely in the mountains Friday morning with the threat
progressing southward and diminishing a bit during the day as the
front slips southward. Cool high pressure will build in behind the
front for Saturday through next Tuesday. Minimum temperatures
during the period will range mainly from the 30s north to near 50
along the coast. High temperatures will be mainly in the 50s north
to 60s south. After Friday, the next threat of any significant
precipitation appears to be late next week.
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
Short Term...VFR conditions except locally IFR/LIFR conditions
between 08-12z Thu and again 08-12z Friday in river valley stratus
Long Term...MVFR to IFR conditions expected Friday in status and showers
gradually improving from north to south as the cold front slips
southward. Except for early morning valley fog, VFR conditions are expected
Saturday through Monday.
Short Term...Quiet on the waters with winds and seas remaining
below SCA criteria through Thursday. Seas over the outer waters may
approach SCA condition over the outer waters along the midcoast
Long Term...Seas may be near SCA criteria Friday. Winds and seas
expected to be below SCA criteria Saturday through mid week next