Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 240214
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
914 PM EST Thu Nov 23 2017

.SYNOPSIS...
A weak upper level trough of low pressure will move across the
region tonight bringing some clouds and maybe a few flurries in
the mountains. High pressure moves off to the east Friday
allowing a warmer southwest flow to develop that will continue
into Saturday. Another weak cold front crosses the region late
Saturday bringing widely scattered showers. A cold upper trof
settles over the region Sunday with possibly some scattered rain
or snow showers and colder temperatures. More high pressure
builds in for the start of next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
915 PM Update...Have updated the forecast...mainly for sky cover
based on latest satellite trends. Mid deck has made it to the ME
coast and should persist until short wave passage just after
midnight. Thereafter, locations downwind from the mountains
should clear out. Otherwise, have adjusted temperatures a little
bit but forecast remains largely on track.

530 PM Update...Have updated the forecast this evening mainly
for cloud cover. An approaching short wave trough has spread an
expansive deck of mid and high clouds over much of the CWA this
evening. This will make it mostly cloudy for several hours, but
a clearing trend is foreseen later on. Otherwise, no
significant changes.

Previously...

Weak 500 mb trough will graze the nrn CWA tonight, and spread
some clouds across the entire area through this evening, and
perhaps produce some snow showers or flurries in the mountains.
Actual best chc of snow in the north will come in the surge of
westerly flow behind the trough after midnight, air little
dynamic forcing ahead of it.

Mins are a bit of challenge, as clouds start the evening, with
clearing late. However along with the clearing comes increasing
W flow on the boundary lyr, and this may limit rad cooling in
all but the most sheltered areas. In the N, clouds will be
lingering all night, so limited cooling there. This should
bring us lows in the in the 20s, coolest N, and warmest S,
although temps may dip this evening and hold steady thru the
rest of the night.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Sfc ridge passes to our south, and the west flow gradually
shifts to SW during the day, with warner air starting to move
in. Some lingering clouds in the mountains should begin to
clear briefly in the afternoon, but otherwise mostly sunny with
highs ranging from 35-40 in the mountains, to the mid-upper 40s
along the cost and in srn NH.

Another round of clouds begin to move in Friday night, as WAA
starts up again ahead of sfc low which tracks well to our north
across Quebec. SW flow increases and with clouds rolling in
lows once again should be early in the night, with temps
steadying or rising after midnight. those lows will be mild for
late November, generally ranging from the mid 20s to mid 30s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
The deterministic models are in decent agreement on the long
wave pattern through early next week. We begin the period with
digging shortwave energy approaching from the Great Lakes. In
response...the approaching upper trough eventually goes negative
tilt by Sunday. At the surface...low pressure over northern
Quebec will drag a trailing cold front accompanied by showers
across the area late Saturday preceded by a warm southerly flow.
The front will drift only slowly offshore Saturday night and
Sunday as it becomes nearly parallel to the upper flow. Low
pressure will develop along this boundary on Sunday and rapidly
intensify as the upper trough goes negative tilt...but too far
offshore for any meaningful impacts to our sensible weather. The
upper trough will lift out during Monday with rising heights
and resultant ridging downstream of an upper trough over the
western CONUS providing the forecast area with several days of
mild weather to begin the new work week.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Short Term...VFR and light winds through Friday night.

Long Term...

Sat PM - Sun AM...Areas of MVFR in -shra and MTN -shra/-shsn.

&&

.MARINE...
Short Term...SCA for seas will hold through the night, as 5-6 ft
seas should persists until after midnight, especially away from
the immediate coast. There should be a short-lived break from
SCA on Friday, but increasing SW flow will likely lead to SCA by
Friday night.

Long Term...

Sat...Small craft conditions are likely.

Sun - Tue...Small craft conditions are possible outside the bays.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory for hazardous seas until 9 AM EST Friday
     for ANZ150-152.

&&

$$

NEAR TERM UPDATE...MLE


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