Area Forecast Discussion
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FXUS61 KCAR 252057
Area Forecast Discussion
National Weather Service Caribou ME
457 PM EDT Tue Oct 25 2016
Low pressure over the Maritimes will slowly dissipate and move
to the southeast through Wednesday. High pressure will cross the
region Thursday. Low pressure will approach Thursday night then
cross the Gulf of Maine Friday.
.NEAR TERM /THROUGH WEDNESDAY/...
Surface low pressure over the Maritimes combined with an upper
level trough of low pressure across our area will continue to
circulate moisture south across the region tonight into Wednesday.
This will continue produce snow showers over the north with a mix
of snow and rain showers Downeast tonight. The surface low
dropping southeast through the Maritimes later tonight into
Wednesday morning will pull a surface shortwave trough south
through the Downeast region enhancing rain and snow shower
activity Wednesday morning. Scattered snow showers will continue
across central and northern areas Wednesday. Skies will remain
cloudy across the region as deep moisture remains over the area.
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
High pressure will cross the region Wednesday night through early
Thursday, then begin to move east later Thursday while low
pressure moves east across the eastern Great Lakes. Expect
decreasing clouds Wednesday night, with generally partly sunny
skies Thursday. However, cloud cover will begin to increase later
Thursday across western portions of the forecast area in advance
of the approaching low. A secondary low will begin to develop
along the New England coast Thursday night, with precipitation
expanding northeast across the forecast area. Based on
temperatures and critical thicknesses, expect precipitation to be
a rain/snow mix Downeast, with snow across northern areas. Light
snow accumulations are possible across northern portions of the
forecast area Thursday night with accumulations generally an inch
or less, though slightly greater accumulations are possible across
the higher elevations of northern Somerset and northern/central
Piscataquis counties. Any snow accumulations Downeast Thursday
night are expected to be a half inch or less. The surface low will
track across the Gulf of Maine Friday along with a closed upper
low. Uncertainty still exists Friday regarding precipitation
totals and types. Generally expect the heavier precipitation
across Downeast areas Friday, with lesser precipitation totals to
the north. The least precipitation should occur across the Saint
John Valley where high pressure ridged to the north will limit
totals. Expect precipitation in the form of rain Downeast Friday.
Across central portions of the forecast area expect a snow/rain
mix during the morning to transition to mostly rain during the
afternoon. Although temperatures aloft remain cold enough to
support snow across northern areas, boundary layer temperatures
are more marginal. Precipitation type uncertainty is greatest
north of a line from Dover-Foxcroft to Topsfield. Across northwest
areas...the Saint John Valley and higher terrain expect
precipitation to remain mostly in the form of snow. Across the
remainder of northern Maine expect snow in the morning to
transition to a snow/rain mix during the afternoon. However, a
slight change in temperature and elevation could determine whether
precipitation remains snow or transitions to a rain/snow mix.
Additional snow accumulations are possible across northern areas
Friday with the better chances of accumulation across northwest
and extreme northern areas along with the higher terrain.
Potential additional snow accumulations at lower elevations will
be dependent on precipitation type and intensity. Temperatures
will be at below normal levels Thursday/Friday.
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
An unsettled weather pattern will persist through the extended
period of the forecast. A mature low will be moving through the
Gulf of Maine at the start of the period. By Saturday morning the
low will move to central Nova Scotia, a high pressure ridge will
briefly build in Saturday morning, and move east of the area by
Saturday afternoon. A low moving across the northern Great Lakes
region. Its associated frontal system will extend into western
Maine. The front will extend across the state by Saturday evening.
The associated cold front will move through early Monday morning
and higher pressure will again ridge across the area. The ridge
will remain across the state through Tuesday morning. A warm front
will move into western Maine Tuesday morning, the associated cold
front Tuesday evening. Higher pressure will dominate the weather
through the end of the period.
Loaded a blend to smooth out the minor differences in the models.
Loaded NAWAVE4 for seas in the coastal waters. Loaded windgust by
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
NEAR TERM: IFR conditions will likely persist across the north
tonight through Wednesday. VFR conditions Downeast tonight should
drop to MVFR on Wednesday in lower clouds and showers.
SHORT TERM: Occasional MVFR conditions are possible early
Wednesday night. Otherwise, generally expect VFR conditions
Wednesday night into Thursday. Conditions will lower to MVFR/IFR
levels Thursday night. MVFR to LIFR conditions are expected
Friday through Friday night. Occasional MVFR conditions are
possible Saturday. MVFR/IFR conditions are possible Sunday.
NEAR TERM: An SCA will continue for the offshore waters through
Wednesday for wind gusts up to 30 kt. Winds should be below SCA
over the intracoastal waters.
SHORT TERM: Small craft advisory conditions are expected
Wednesday night. Conditions are expected to be below small craft
advisory levels Thursday. Conditions could then approach Gale
levels later Thursday night, with Gale conditions possible
Friday. Visibilities will be reduced in rain Thursday night into
MARINE...Small Craft Advisory until 2 AM EDT Thursday for ANZ050-051.