Area Forecast Discussion
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FXUS61 KGYX 251411
Area Forecast Discussion
National Weather Service Gray ME
1011 AM EDT WED MAY 25 2016
Sunshine and warmer weather will return today ahead of a cold front.
The front will bring clouds and a few showers and thunderstorms
to the area this afternoon and early evening. A ridge of high
pressure will build over the area tonight... then hold over the
region on Thursday as a warm front approaches from the west. The
warm front will stall over the region Thursday night and Friday
and will finally push east of the region on Saturday. A cold front
will cross the region Saturday night then stall just to our south
on Sunday. The front will return north as a warm front on Memorial
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Threat for some hail and gusty winds continues this afternoon and
evening for Northern NH and adjacent western Maine. Coordination
has occurred with Caribou for some enhanced wording for hail and
Have updated the grids based on latest observations and mesoscale
model data. Low level moisture continues to increase over the
region while the atmosphere remains capped. Fog has mixed out in
many inland areas and destabilization has begun. Northwest front
aloft, favorable for strong thunderstorms will accompany a cold
pool aloft and surface cold front as it passes through the region.
Steep low level lapse rates will develop with the
afternoon surface heating. CAPE values will continue increase
while the cap is breaking. However, highest CAPE values, AOA 1000
J/KG may remain north of the border. Will continue to highlight
the threat for storms over the afforementioned area in our
products and social media.
May have to nudge temperatures upward along the coast, depending
on whether there will be a significant onshore flow or not. In the
meantime, portions of southernmost NH may nudge 90 degrees this
At o6z...weakening low pressure surface and aloft was over the
gulf of Maine. While showers had ended...clouds and areas of
drizzle and fog were lingering across the forecast area.
Conditions will improve later this morning as the system slides
well east of the area. The clouds and fog will break by shortly
after sunrise with southerly flow and 850 millibar temperatures
near plus 14C boosting temperatures into the 80s away from the
coast where onshore trajectory will temper the heat today.
shortwave impulse on GOES Water Vapor imagery north of the Great
Lakes will race eastward with associated cold front over Quebec
approaching international border region late today. While moisture
and wind fields aren`t overly impressive...the modified BUFKIT
forecast soundings for late today suggest gusty winds and small
hail are a possibility with the stronger cells. I`ve included
enhanced wording in the grids for that area.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
convection will quickly end this evening with loss of heating and
as upper support exits the coast. Clearing and cool tonight behind
the front with some late night valley stratus and fog as a ridge
of high pressure noses in from the north. Lows tonight will range
from upper 40s near the international border to around 60 at the
New Hampshire seacoast. The ridge will crest across the area on
Thursday with sunshine and warm temperatures. Highs will range
from the mid 70s to lower 80s...before turning cooler by afternoon
along the coast in a developing seabreeze.
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Model guidance is in good agreement on overall extended pattern
into next week. Ridging will build into the region from the Wrn
Atlantic...with the axis running thru New England. It will be a
good potential pattern. Potential for some above normal
temps...perhaps even 90...to work into parts of Nrn New England.
But also the potential for a passing s/wv trof to knock the ridge
down and backdoor some of the area. As things stand this
morning...there is some consistency and consensus that a hotter
day is possible Sat...while a backdoor cold front is possible Sun
especially for Ern zones. With that boundary separating hot and
cold air lingering nearby...a focus for showers or tstms will also
be present into early next week. Cannot completely rule out rnfl
in the extended...but there is not enough confidence for likely
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
Short Term /through Thursday/...Sct MVFR across the mtns this PM
and evening with brief lcl ifr psb in -shra/tsra. Areas of mvfr
and lcl ifr dvlpg btw 08-12z Thu in valley stratus and fog...bcmg
vfr throughout aft 13z Thu.
Long Term...In general high pressure looks to be in control of the
forecast area thru early next week. VFR conditions should prevail
as a result. However...there will be a risk for scattered shra or
maybe even tstms and MVFR or local IFR that go with them.
Short Term /through Thursday/...No flags expected.
Long Term...With ridging generally in place over the waters thru
the extended...SCA conditions are not expected.
Warm temperatures today but with scattered showers and
thunderstorms later today. Good relative humidity recovery follows
for tonight. Thursday will be one of the only dry days of the
week. Afternoon relative humidity values on Thursday may hover
near 30%...but winds will be light. We are forecasting all areas
to receive rainfall this week albeit light.