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Area forecast discussion...updated
National Weather Service Gray ME
916 am EDT Wed Sep 18 2019

cool high pressure builds across the forecast area today and
tonight and will allow for a frost in many areas overnight.
Increasingly warm temperatures are expected to arrive by the end
of the week and for the weekend, most likely well above normal.
A cold front will approach for Monday and Tuesday with a chance
of showers as it moves through.


Near term /until 6 PM this evening/...
915 am update...
adjusted temperatures and dew point trends slightly, otherwise
no changes needed. A sunny but cool day is expected.

645 am update...little change to the going forecast for the near
term. Did however add a coastal flooding section below to
elaborate a bit on the potential for rip currents Friday into
the weekend.


A mostly sunny day is in store today after early morning valley
fog dissipates. Light wind and highs in the 60s will be the
rule. Winds turn locally onshore this afternoon.


Short term /6 PM this evening through 6 PM Thursday/...
surface high pressure centers overhead tonight. This will allow for
excellent radiational cooling conditions which should allow for
a good portion of the forecast area to receive a frost. Several
zones will likely experience a freeze as well. Have issued
frost and freeze advisories based on zone average low
temperatures, which have been populated with a blend of MOS mins
with local climo incorporated. Left leeway for the dayshift to
expand (especially southward) if necessary. Valley fog will
likely develop as well which is quite common this time of year
on good radiating nights.

Sunny and a bit warmer with high pressure right overhead for
Thursday. Postcard perfect in all likelihood.


Long term /Thursday night through Tuesday/...
in the big picture we see a ridge over central North America
trying to spill eastward into the northeast. A persistent cut
off low off the East Coast has been blocking its progress
eastward, but as Hurricane Humberto gets slung around the
eastern side of this low, the upper low itself will gradually
push away and open up the door for the ridge to build east.
Along with it expect warmer temperatures venting out of the
southern US through New England. A trough moving through Canada
will push the ridge eastward and send a cold front toward our
area early next week. This seems likely to arrive on Monday.

Surface high pressure axis remains in the area Thursday night
so we should see another good radiational cooling night.
However, some warmer, more moist air will have advected in from
the northwest on Thursday which will give US a higher floor for
the temperatures. Most areas will drop into the 40s, though a
few upper 30s are possible in colder valleys. By Friday the
warmer, more humid air will finally be felt with temperatures in
the 70s to near 80 for much of the area. The high temperature
may warm a degree or two each day through Saturday and Sunday
when more and more 80s will be observed.

There is general agreement among the models that a cold front
will push through the region early next week... broadly centered
on Monday. However, the initial push with this front blows by to
our north while a secondary area of energy may form at the base
of the upper trough to our southwest. Generally speaking we
should see a chance of showers as the front moves through, but
being in between the northern and southern waves may keep rain
chances a bit lower in our area. If the secondary wave does
become more significant then it could allow showers to continue
into Monday night in southern areas. Conditions should become
drier and cooler behind the front for the middle of next week.


Aviation /13z Wednesday through Sunday/...
short term...VFR conditions expected today through Thursday
other than LIFR in valley fog between 06z and 13z Thursday.
Light winds, becoming locally onshore this afternoon.

Long term...VFR conditions expected aside from early morning fog
I the valleys right through the weekend.


short term... winds and seas remain below Small Craft Advisory criteria through
Thursday with building high pressure.

Long term...light offshore winds expected through Friday and
Saturday as high pressure gradually crests over the region. A
south to southwest flow picks up on Sunday on the back side of
the high and in advance of an approaching cold front. It's
possible that some wind gusts could approach 25 knots Sunday into
Monday. Long period swells, possibly as high as 10 feet will
likely begin to affect the waters Friday.


Gyx watches/warnings/advisories...
ME...freeze warning from midnight tonight to 9 am EDT Thursday for
Frost advisory from midnight tonight to 9 am EDT Thursday for
New Hampshire...freeze warning from midnight tonight to 9 am EDT Thursday for
Frost advisory from midnight tonight to 9 am EDT Thursday for



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