Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 211017
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
617 AM EDT Thu Sep 21 2017

.SYNOPSIS...
Jose will wobble around south of Cape Cod into the weekend,
gradually weakening with time. It will produce some gusty winds
at times along the coast into Friday and waves of high clouds.
Otherwise high pressure will be the main feature and build south
into the region as Jose weakens, making for fair weather and
temperatures running well above normal Saturday through at least
Tuesday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
615 am...Only minor changes to sky, to cover some patchy stratus
early this morning, and T/Td. which were just tweaked based on
current obs. Otherwise forecast unchanged. 10Z obs showing winds
starting to gust up.

Previously...Jose should stop its slow easterly movement this
morning and then begin to shift very slowly back to the west.
This had helped keep the winds generally fairly light across the
CWA, but the shift back to the west should help tighten up the
pressure gradient between the sfc high just to our north, so
expecting to winds to pick up this afternoon, if not this
morning, and it will become breezy, mainly along the coast with
gust of 25-30 mph in the coastal zones and 20-25 mph in the next
tier of zones just off the coast. For the most part should just
see cirrus today, but it may come in thicker waves, so could
see periods where it more cloudy, but overall partly sunny
should cover it.

Even though some cooler air aloft is moving in, it`s coolness is
all relative and still above normal with 850 temps still around
12C, and with NNE winds should see some downsloping as well,
especially in the CT valley, where highs could reach 80. The
rest of the CWA should be in the low to mid 70s today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Jose will become completely separated from any 500 mb flow by
tonight, so it will remain nearly stationary, although with a
bit of a westward drift through Friday. It will start to gradually
weaken tonight as well, as it wobbles around near the nrn
boundary of the gulf stream, so it may tap into some fuel in
the warm waters on the nrn of the gulf stream, and will tend to
hang on for a few days. Confidence is low in the little
movements and their effect on our CWA, but should winds persist
into tonight, although less gusty as mixing height lowers
overnight. Those NNE winds will tap into some cooler sfc air to
our N, so lows will drop into the mid to uppr 40s in the N, and
in the low to mid 50s S.

Models do suggest a surge of some clouds and maybe some light
SHRA moving into the coastal zones late tonight into Fri
morning, but with drier air working from the north, we may see
it drying up before it gets here again, and forcing is not as
strong as it was Tue into Wed, when we were lucky to squeeze out
a tenth or two precip in some spots. Highs may end up a little
cooler on Friday, especially in coastal areas, but should see
most places reach 70 and generally will see highs 70-75.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The models are now in decent agreement on the long wave pattern
through much of next week. We begin the period with an upper
ridge across northern New England and the remnants of Jose
meandering well offshore to our south and east. The ridge will
continue to strengthen as we head into the weekend...at which
time the remnants of Jose will finally be kicked well offshore.
The eastern ridge and western trough will then hold across the
CONUS through the start of the new work week with predominantly
dry weather and abnormally warm temperatures to continue. By mid
week...the ridge begins to weaken as the upper trough progresses
eastward into the central CONUS. This opens the door for the
tropical system to advance northward off the east coast...before
being swept well offshore into the north Atlantic ahead of the
advancing upper trough. The interaction of an approaching cold
front and tropical moisture could produce some much needed rains
late next week.

&&

.AVIATION /10Z THURSDAY THROUGH MONDAY/...
Short Term...Seeing mostly VFR this morning, although may see
some patches of fog at KLEB, as we have seen already tonight,
and also see some MVFR cigs at KRKD. Should see steadily VFR
everywhere by around 12Z, which will hold into this evening.
Coastal terminals could see some wind gusts to around 25 kt
this afternoon.

Long Term...

Sat - Mon...Lcl IFR psb in valley fog btw 09-12Z each day.

&&

.MARINE...
Short Term...Jose will wobble around south of the Cape Cod today
through Friday, and will see seas and winds surge up this
afternoon into tonight, before they start to gradually diminish
on Friday. Will probably see SCA conditions for part of Friday,
at least outside the bays, especially for haz seas, but have
held off for now, and see how things develop before extending.


Long Term...SCA conditions are likely Friday through the
weekend, mainly for seas, as Jose continues to meander south of
Nantucket.

&&

.TIDES/COASTAL FLOODING...
Long period swells will continue through Thursday night. High
tide at Portland is 10.3 ft around 1 AM, which is a little lower
than previous nights, so some minor beach erosion remains
possible.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...High Surf Advisory until 8 AM EDT Friday for MEZ023>028.
NH...High Surf Advisory until 8 AM EDT Friday for NHZ014.
MARINE...Small Craft Advisory until 8 AM EDT Friday for ANZ150>154.

&&

$$
SYNOPSIS...
NEAR TERM...Cempa
SHORT TERM...Cempa
LONG TERM...Schwibs
AVIATION...
MARINE...
TIDES/COASTAL FLOODING...



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