Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 211836
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
236 PM EDT Mon May 21 2018

.SYNOPSIS...
High pressure will slide offshore to the south of New England
this evening. A moisture starved cold front will drop south
from Quebec and stall nearby tonight. This front will return
north as a warm front on Tuesday, spreading showers into the
area. Another cold front drops south through the region
Wednesday. Weak low pressure tracks along the international
border late Thursday into Friday. A frontal system tracks into
the area for the holiday weekend bringing widespread showers.

&&

.NEAR TERM /UNTIL 8 PM THIS EVENING/...
At 18z a 1025 millibar high was draped across the lower Great
Lakes. A weak cold front extended from the rooftop of Maine
through the Saint Lawrence Valley. GOES visible imagery showed
a band of broken mid cloud with the cold front otherwise skies
were clear across the forecast area. The weak boundary will drop
south across the area tonight and stall. GOES water vapor shows
an impulse over the northern plains. This impulse and an
associated surface low will race eastward with clouds arriving
from west to east across the area during the morning hours.

&&

.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/...
On Tuesday...the impulse and surface low will cross the region
and push the boundary northward as a warm front into southern
sections of the forecast area. A mostly cloudy day with showers
developing from west to east by afternoon. It`ll be cooler than
today with highs in the 60s to around 70. Showers taper from
west to east Tuesday night as the impulse and surface low slide
offshore with patchy fog developing. QPF from this system will
average from 0.10 to 0.20 inches.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
There will be a gradual clearing on Wednesday. However an upper
level trough will linger to the west which may allow for some
destabilization and the threat of an afternoon or evening shower
or possibly a thunderstorm.

A ridge of high pressure over the region early Thursday will
give way to the approach of a warm front. H8 temperatures in the
+10C to +12C in southern Canada will advect eastward. This will
allow for much milder conditions by Friday as Maine and New
Hampshire will be in the warm sector along with scattered
showers in the northern mountains. This front will become
relatively stationary over the region Saturday. Temperatures
will lower from the 80s to the 70s in most sections except for
southwest New Hampshire. Expect more shower activity by Sunday
as the front settle south to the southern New England coastline.
12Z model suite in relatively good agreement with the front
slipping south of our region.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
Short Term /through Tuesday Night/...Gusty westerly winds will
diminish by early evening. VFR through tonight. Areas of MVFR
developing aft 16z tomorrow in shra. LCL IFR aft 03z Wed in fog.

Long Term... Generally VFR conditions with a few scattered
showers and possibly a thunderstorm Wednesday afternoon and
evening. More showers with lowering ceilings Friday night into
Saturday.

&&

.MARINE...

Short Term /through Tuesday Night/...
Westerly flow could briefly approach small craft in gusts
through early evening as a weak boundary drops south across the
waters.

Long Term...Seas will gradually build to near SCA thresholds in
the proximity of a warm front Friday into Saturday.

&&

.FIRE WEATHER...
Good relative humidity recovery expected tonight with moderate
to high relative humidity tomorrow and tomorrow night in
showers.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Beach Hazards Statement until 8 PM EDT this evening for
     MEZ023>028.
NH...Beach Hazards Statement until 8 PM EDT this evening for NHZ014.
MARINE...None.

&&

$$
NEAR TERM...Schwibs
SHORT TERM...Schwibs
LONG TERM...Cannon


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