Area Forecast Discussion
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FXUS61 KGYX 270004
Area Forecast Discussion
National Weather Service Gray ME
804 PM EDT Wed Apr 26 2017
Low pressure will slowly weaken and fall apart over Northern New
England allowing for overcast skies and damp conditions to
persist through Thursday night. A cold front will help to sweep
out the cool and wet conditions Friday...with a trend towards
warmer temperatures to start the weekend. That may be short
lived however...as cooler air tries to slip back in from the
north Sunday into Monday.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
755 pm...Stacked low south of Long Island this evening will
continue to shift east and weaken tonight, and this should
slowly move flow of showers off the Gulf of ME east as well, and
generally reduce the coverage. Still, the lack of flow as col
moves overhead, and any low level flow generally onshore will
make for fog and drizzle persisting overnight into Thu morning.
Some areas will see dense fog later this evening and overnight.
Temps may drop off a few degrees overnight, but should bottom
out in the upper 40s to low 50s.
Low pressure off the coast of New Jersey will continue to slowly
drift northwards and fill this evening. As it does rain will
continue to rotate around the low bringing periods of showers
through the evening. Between the rain showers low clouds and
drizzle remain keeping everywhere damp.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Through the overnight hours the rain will come to an end but
onshore easterly flow over the mid 40s ocean will continue. This
moisture will allow for fog to develop. Dense Fog is possible
along the coast with some sites to our south in Mass already
reporting 1/4 mile visibility. High res ensemble also shows a
significant chance of low visibilities and a Dense Fog Advisory
may be needed overnight and into early morning. Have opted not
to issue one at this time mainly due to the uncertainty in the
geographical area. Some mountain sites have already seen dense
fog as well as a few coastal locations. Expect fog to be
widespread by some uncertainty still exists in the extent of the
very low visibilities so have opted for areas and patchy dense
fog for this forecast.
As we move into the day on Thursday we`ll see a slight
improvement in visibility through the morning but skies will
remain overcast with periods of drizzle possible through the
morning as the low continues to fall apart through the day.
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
The extended forecast looks to feature generally Sly flow over
the forecast area. L/wv trofing is forecast to set up to our
W...allowing S to SW flow aloft and advection of warm fronts
towards the area. Of course banking on warm fronts to push thru
the forecast area is typically playing with fire...especially
this time of year. The first comes following the passage of a
s/wv trof Fri. After some early day showers...the question is
how far N the warm front can make it into the area. If it can
make steady progress thru the region it will be a mild day...but
it may get hung up overhead and lead to a pretty large range in
temps from N to S. Thru the rest of the weekend the front aloft
looks to move into Quebec...but high pressure forecast to build
N of the area will tend to lock the surface front in place. That
would mostly likely lead to another round of rain/drizzle and
low clouds until early next weekend when the cold front sweeps
out the low levels. At this time no significant amounts of
precip look likely...with either warm frontal forcing to our N
or more progressive cold fronts moving thru the area.
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Short Term... Widespread IFR conditions will deteriorate into
LIFR overnight with 1/4SM fog at coastal sites. To the west in
the CT River valley conditions will improve to MVFR for Thursday
while across the coastal plain and mountains IFR with periods of
drizzle will linger through Thursday.
Long Term...A series of warm fronts will try and lift into Nrn
New England thru the weekend. This will most likely lead to
periods of widespread cloud cover. Significant periods of MVFR
CIGs are likely...and areas of IFR could form in the overnights
in onshore flow. Any IFR conditions would be most likely near
the coast...with LEB and HIE being least likely to see
Short Term... Have dropped the Small Craft in favor of just the
Hazardous Seas Headline. A few gusts to 25kts are possible
this afternoon but winds will generally be diminishing. Seas
will remain 4-6ft through Thursday as the low pushes easterly
Long Term...Persistent Sly flow across the waters will keep seas
near 5 ft outside of the bays into the weekend. The warmer wind
over cold water will likely keep wind gusts below
thresholds...but a SCA may be needed for hazardous seas.
Drizzle, low clouds and damp conditions will continue through
the region today as low pressure east of New Jersey slowly fills
Despite the damp conditions QPF amounts have been a bit lower
than expected with totals around an inch along the coast and
half an inch in the headwaters. An additional quarter inch is
possible through the afternoon and evening. Rivers should stay
below flood although a few will exceed action stage including
the Saco at Conway and the Presumpscot at Westbrook.
A Coastal Flood Advisory is in effect for tonight. High tide at
Portland is 11.5ft at 11:53pm. Onshore flow may create a minor
storm surge pushing coastal locations to near flooding.
ME...Coastal Flood Advisory until 2 AM EDT Thursday for MEZ023-024.
NH...Coastal Flood Advisory until 2 AM EDT Thursday for NHZ014.
MARINE...Small Craft Advisory for hazardous seas until 8 PM EDT Friday