Area Forecast Discussion
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FXUS61 KGYX 170125
Area Forecast Discussion
National Weather Service Gray ME
825 PM EST Thu Feb 16 2017
Low pressure continues to pinwheel away from New Hampshire and
western Maine tonight. Some lingering mountain snow showers will
be possible overnight and into Friday before high pressure
builds into the region to start the weekend. Mostly sunny skies
are expected along with a warming trend through the weekend. By
Sunday we may even be looking at high temperatures well into
.NEAR TERM /TONIGHT/...
Some light snow showers have snuck through the mountains and
made their way into parts of central New Hampshire. Have updated
precipitation chances a bit to adjust for this. Otherwise no
significant changes were needed. Clear sky downwind of the
mountains will allow for better cooling there, but winds are
expected to keep things mixed tonight.
Cyclonic flow around a deep low pressure over the Canadian
Maritimes will continue tonight. Downslope flow is helping to
dry out areas downwind of the mtns...but upstream lingering low
level moisture is keeping clouds and snow showers going. These
will linger into the overnight...with a couple inches
accumulation possible in the favored NW facing slopes. Boundary
layer remaining mixed tonight will keep temps from getting too
cold in the wake of the departing low.
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
Dry...cyclonic flow will continue across the area Friday into
Friday night. Gusty NW winds possible during the day...with
mostly sunny skies. Some high clouds will lift over the area in
the evening...and may become a little dense at times downwind of
the mtns. This should keep temps up a little Friday night.
.LONG TERM /SATURDAY THROUGH THURSDAY/...
High impact weather: None
A high amplitude long wave pattern continues through the start
of the weekend with a strong ridge built up through western
Canada and a 500mb trough over Quebec and the Northeast.
For the start of the weekend the upper level low will slowly
move east allowing warmer air to make its way into northern New
England. Northwesterly flow around the periphery of the low
over the maritimes will continue, with a weak wave moving
through overnight Saturday into Sunday. This will result in
upslope snow showers for far northern New Hampshire and Western
Maine. Have increased the snow amounts above guidance for the
weekend. While there won`t be any heavy snow the light showers
will continue through most of the weekend and favored locations
could see as much as 4-6" in 36 hours.
To the south warm air advection will begin bringing
temperatures above freezing for the entire forecast area for
Saturday. On Sunday that warmth will continue to increase as
high temperatures push into the mid 40s south to upper 30s
Surface high pressure looks to remain in control through the
beginning of next week. Forecast confidence diminishes
significantly at the start of the week as the hemispheric
pattern develops a block in the Atlantic. This puts northern New
England in the squeeze between a strong ridge over the great
lakes and a trough extending from Labrador to possibly as far
south as southern Nova Scotia. Have stuck with a blend of
guidance as we wait to see where it evolves.
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
Short Term...VFR expected tonight outside of some MVFR ceilings
early at Whitefield. Northwest winds expected again on Friday
gusting to 15 to 25 KT.
Long Term...VFR through most of the long term. Northern
Mountains including HIE will see some light snow showers in
MVFR Saturday afternoon into Sunday.
Short Term...NW flow will continue into Friday. Mainly 25 to 30
kt gusts expected...except for the far Ern waters where a
couple 35 kt gusts are possible. I have dropped the gale
warnings to SCAs for all waters...with bays expiring early Fri
where winds will diminish first. Winds and seas on the outer
waters will diminish Fri evening.
Long Term... Very quiet stretch on the waters with winds and
waves staying below small craft criteria.
MARINE...Small Craft Advisory until 7 AM EST Friday for ANZ151-153.
Small Craft Advisory until 1 PM EST Friday for ANZ150-152-154.
NEAR TERM UPDATE...Kimble