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000
FXUS61 KGYX 251123
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
723 AM EDT Thu Apr 25 2024

.SYNOPSIS...
Dry high pressure moves into and across the region today
through Saturday. A warming trend can be expected over the
weekend with chance of showers Saturday night or Sunday. Warmer
weather is then expected early next week for most areas except
possibly the coastal plain with scattered showers.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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730 AM Update... Minor changes to reflect latest observational
trends. Temperatures are already beginning to rebound now that
we are past sunrise.

Previously...
Nighttime microphysics satellite imagery early this morning
shows clear skies across the region. West-northwesterly winds
remain gusty in most locations with some gusts still between
25-30 mph. Breezy conditions will persist through daybreak in
most locations, although a few valley spots could briefly
decouple. Current temperatures are primarily into the 20s but a
few lower 30 degree readings persist over southern NH and
coastal western ME. A few additional degrees of cooling can be
expected through daybreak.

Surface high pressure will remain over the region today but a h5
trough axis will keep temperatures aloft on the cool side. This
will result in mainly sunny skies and low afternoon relative
humidity as we mix into a very dry airmass aloft. Afternoon
relative humidity will fall into the middle teens to 20s percent
range in most areas, lowest south of the mountains and away from
the immediate coastline. West-northwesterly winds will also
persist at between 10-15 mph, gusting to around 25 mph at times.
This combined with the low relative humidity could cause
increased fire weather concerns. Latest hi-res guidance
continues to indicate the development of onshore flow along the
coast by mid-afternoon, which will allow RH to increase over
coastal locations. Given the very dry airmass and abundant
sunshine, went on the warm side of guidance for afternoon high
temperatures. This places readings into the middle to upper 50s
for many areas south of the mountains and away from the
immediate coast.
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&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Mainly clear skies will persist tonight with winds quickly
decreasing this evening with the loss of daytime heating/mixing.
This will set the stage for likely excellent radiational cooling
conditions despite the relatively short nights of late April. As
a result, used MOS guidance for overnight lows and pushed down
the normally colder valleys down a few additional degrees. This
places lows into the teens across the normally colder interior
valley locations with 20s in most other locations.

Sunny skies and dry conditions will continue on Friday with h850
temperatures warming by around 5C. This combined with deep
afternoon mixing will allow for warmer high temperatures into
the upper 50s to middle 60s south of the mountains, warmest in
southern NH. Relative humidity will once again fall into the
teens to 20s percent range during the afternoon hours. Surface
westerly winds will be weaker as compared to today and this will
likely allow for an earlier start to the seabreeze and it will
likely penetrate further inland with increasing relative
humidity behind it.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
High pressure will remain anchored over northern New England as
we begin the long term portion of the forecast. With clear
skies, light winds and low dew points, expected a large diurnal
curve with lows dropping below freezing in all areas with 20s
in the north and lower 30s in the south.

More sunshine is expected on Saturday as the large ridge of high
pressure begins to slip off the Northeast coastline. A
southwesterly flow will develop by late in the day and will
allow temperatures to climb through the 60s.

00Z model runs remain in relatively good agreement allowing a
warm front to approach the region from the west Saturday night.
This will allow for a few showers to enter the region, mainly
over northern and western areas. Scattered showers will continue
on Sunday with readings in the 60s in most areas. The exception
will be coastal areas where temperatures will be in the 50s.

Temperatures will peak early next week. H8 temperatures near
+12C and some sunshine will allow temperatures to reach the 70s
over southern New Hampshire and 60s over interior Maine. Very
cold water temperatures in the Gulf of Maine will allow for
chilly temperatures will onshore winds and readings in the 50s.
A nearly stationary from will allow for a few more scattered
showers across the region.

Temperatures will begin to cool off by midweek next week with
plenty of cloud cover and some cold air advection.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Short Term...VFR conditions prevail today through at least
Friday. West-northwesterly winds will continue today with gusts
up to around 25 kts before becoming light and variable tonight.
A seabreeze will develop between 18-20Z today with winds
becoming southerly at KPSM, KPWM, and KRKD. Westerly winds
continue on Friday before another seabreeze develops after 16Z.
No LLWs is expected.

Long Term...VFR conditions continue Saturday with high pressure
overhead. Scattered -SHRA arrives Saturday night through part
of Sunday with possible lower ceilings although the any rainfall
would likely be brief at one location. The same is expected for
early next week although chances of rain will be lower.

&&

.MARINE...
Short Term...West-northwesterly winds of 15-20 kts continue
today before becoming light and variable tonight and then west
at 10-15 kts on Friday. Seas will decrease below 5 ft by early
this afternoon over the outer waters.

Long Term...Winds and seas to remain below thresholds hazardous
to small crafts as high pressure builds over the waters Saturday
and into early next week.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
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ME...None.
NH...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for ANZ150-
     152-154.
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&&

$$

NEAR/SHORT TERM...Tubbs
LONG TERM...Cannon