Area Forecast Discussion
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FXUS61 KGYX 121037 AAA
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
537 AM EST Thu Jan 12 2017
It will be another warm day across northern New England today,
with periods of rain showers expected. A cold front will drop into
the area from the northwest tonight and usher in colder air on
gusty northwest winds on Friday. The cold weather will last
through the weekend as high pressure builds across the area.
Expect a gradual warm up next week as warm air pushes north into
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --540 AM Update...
Warm advection showers are now moving through NH and Maine with
temperatures gradually increasing each hour. Made minor changes to
PoPs and updated temperatures to match current speed of warming.
Some more robust convection is to the west and will be arriving in
northern NH and the western Maine mountains shortly. Once again
most of this is rain but there may a few pockets of freezing
rain in the valleys which will diminish quickly as temperatures
increase this morning.
Deep low pressure was moving through northern Canada this
morning, dragging a cold front through the Great Lakes region and
into the southern Plains states. The front will eventually reach
New England late tonight. Before this occurs, warmer air ahead of
the system will continue to nurture scattered warm advection
showers throughout the day. Short wave energy in SW flow aloft is
driving the periodic nature of the showers...and there will be a
couple other batches of precipitation moving through today.
Temperatures will be well above freezing, but rain and fog will
nonetheless make for a dreary day overall.
Temperatures across the region ranged from the upper 20s to
lower 40s and have been rising overnight. Patchy black ice may be
a concern on road surfaces that are below freezing for the next
few hours, however that threat is diminishing. Readings will
ultimately warm into the mid 40s to lower 50s due to the strong
warm advection and SW winds.
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.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Rain over the higher terrain will mix with or change to snow
tonight as temperatures begin to fall. Orographically lifted snow
showers will be the only showers of note overnight. Temperatures
will be on the warm side ahead of the cold front which moves
through overnight. The cold air advection begins in earnest
Friday... and this will have the effect of creating a small
diurnal range between Friday morning`s lows and Friday`s highs...
so that some locations may only warm a few degrees before readings
begin to tumble during the day. NW winds will gust to near 40 mph
making for a blustery and cold day even though skies will be
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Winds begin to diminish Friday evening as high pressure builds
into the area from the west. The high only just barely makes it
toward western New Hampshire by sunrise, so expect winds to remain
strong enough to prevent a strong inversion from setting up,
keeping the low levels mixed. However, temperatures still drop
pretty low on cold advection, with lows below zero to the
northwest of the mountains and in the single digits to the
southeast. The high crosses the area on Saturday with light winds
and a clear sky expected. Temperatures only warm into the teens
and 20s, so it will be a cold day.
A broad area of high pressure remains over the area for the next
several days, but it is briefly broken up by a shortwave trough
which drives a second cold front toward the area Saturday night.
The GFS hits this feature harder than the ECMWF, and there is very
little moisture to work with on this, so in general expect this to
be mostly unnoticed. It could cause an uptick in wind speeds
Saturday night as well as bring some clouds to the mountains which
could prevent an otherwise excellent radiational cooling night.
However, even if these flies disrupt the ointment, there should
still be several hours of good cooling Saturday evening. Based on
the amount of dry air available Saturday evening before the dry
front arrives, there is the potential for temperatures to drop
below zero. Current forecast represents a compromise between the
warm model low temperatures and the much colder temperatures that
Secondary area of high pressure moves across the area Sunday into
Sunday night behind the minor front. Expect temperatures a little
closer to normal on Sunday, generally around freezing for a high.
Sunday night should feature good radiational cooling, but there
will not be quite as much dry air so lows will bottom out in the
teens to near zero.
Models continue to agree on the longwave pattern for the extended
forecast which features a large trough over the southwestern
United States which sends warm air northward into a developing
ridge over the eastern United States next week. The consensus now
favors some of the energy from the southwestern low ejecting
across the center of the country on Tuesday, arriving in New
England Tuesday night, bringing a chance of light rain or snow.
The broader ridging remains through the middle to later part of
the week which signals warm temperatures for New England.
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Short Term...VFR conditions dropping to MVFR early this morning
and then to IFR ceilings and MVFR visibilities as periods of rain
showers become more widespread and clouds thicken and descend.
Cold front will move through tonight after 0Z clearing out some
low level moisture and improving ceilings. Drizzle and fog may
still linger through Friday morning. Gusty SSW winds today will
become WNW overnight and increase with gusts to 35 kts on Friday.
Long Term...High pressure crossing the area should provide light
winds and VFR conditions through the weekend and into early next
week. The only exception could be a period of MVFR ceilings north
of the White Mountains Saturday night into Sunday morning, but
this is still fairly uncertain.
Short Term...Small craft continues today ahead of a cold front and
behind the cold frontal passage as well. A gale watch has been
posted for mid morning Friday through late Friday as the pressure
gradient increases markedly behind the front.
Long Term...Winds diminish Friday evening into Saturday as high
pressure moves in behind the front. A broad area of high pressure
remains over the waters through early next week leading to a
period of light winds and low wave heights.
-- Changed Discussion --ME...None.
MARINE...Small Craft Advisory until 5 AM EST Friday for ANZ153.
Gale Watch from Friday morning through Friday evening for
Small Craft Advisory until 5 AM EST Friday for ANZ150>152-154.
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