Area Forecast Discussion
Issued by NWS Caribou, ME
FXUS61 KCAR 232211
Area Forecast Discussion
National Weather Service Caribou ME
611 PM EDT Thu Mar 23 2017
High pressure will slide south of the area tonight. A warm front
will cross the region on Friday followed by a cold front Friday
night. High pressure will build down from the northwest Saturday
.NEAR TERM /THROUGH FRIDAY/...
6:11 PM Update...Early evening satellite pictures show a clear
sky across the Pine Tree State. Cold air cumulus is evident well
offshore, and thin cirrus is noted moving into central Quebec
well in advance of a warm front that lifts across the region
Friday. A gusty nw wind will rapidly decouple early this evening
with the loss of daytime heating as a surface ridge crests over
the region later tonight. The biggest forecast challenge this
evening will be the temperatures. There will be a good
opportunity for radiational cooling as strong surface based
inversions form. Clouds moving in later tonight may limit the
cooling some, especially across the normally colder broad nw
valleys. In any event, will tweak the temperatures down a bit,
especially as dew points are quite low and below zero in most
areas. Otherwise, no changes to the ongoing forecast at this
time which looks real good.
Previous discussion... Another cold night on tap for the region
as high pressure will crest over the area. High clouds
associated with our next weather system will begin to spread
into western areas late tonight which should help keep
temperatures a bit warmer than what we saw last night. Lows will
be in the single digits north and east, while more southwestern
portions of our forecast area and along the coast will bottom
out at 10 to 20.
Low pressure will slide eastward well to our north, dragging a cold
front/surface trough through the Great Lakes on Friday and into the
Northeast late in the day. This will bring another round of
precipitation to our area, mainly in the afternoon and evening
hours. Although this may start out as snow, temperatures will warm
into the lower and mid 30s by afternoon, so expect many central and
Downeast locations will end up seeing a rain/snow mix or just plain
rain for the bulk of the event, mainly along and south of a Danforth
to Millinocket to Dover-Foxcroft line. This is a fast-moving system,
so don`t expect much in the way of any snow accumulation, even in
those areas that remain cold enough for all snow. Most spots will
see an inch or less, with some amounts up to 2 inches possible in
the higher terrain of the North Woods.
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A cold front will push across the state Friday evening with some
light rain or snow showers still possible, mainly Downeast, during
the evening as the front pushes through. Northern areas will begin
clearing overnight. A large high pressure system will then begin
building down from central Canada on Saturday bringing a mostly
sunny and seasonable day across the north with partial clearing
Downeast. This will be followed by a mostly clear and cold night
Saturday night. The high will be ridging over the area on Sunday as
northern areas remain partly to mostly sunny. Some clouds will start
to increase Downeast as a warm front begins to move in from a large
low pressure system approaching form the Great Lakes.
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Low pressure will approach Sunday night into Monday as clouds
increase from southwest to northeast. Some snow may begin to spread
into southeastern areas overnight Sunday night then continue on
Monday with snow possibly reaching the north late Monday. The snow
may taper off or decrease in intensity Monday night as an initial
wave of low pressure slides off to the east. A larger low will then
approach late Tuesday into Tuesday night spreading snow back across
the area which may change to rain Downeast. Snow north and rain
Downeast are then likely Wednesday as one low lifts north across
Canada and a secondary forms south of the coast and pushes offshore.
The system should consolidate and lift northeast through the
Maritimes on Thursday as drier air returns behind the low.
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
NEAR TERM: Conditions will remain VFR for much of the forecast
period. Clouds will gradually filter in late tonight and then
lower through the day on Friday as precipitation associated with
an approaching cold front moves into the region. While light
snow showers will be possible at all sites by late morning, KBHB
and KBGR will transition to all rain by 18z while northern
locations remain all snow. Conditions will lower to MVFR at all
terminals around 18z and remain so through the rest of the day.
The northern sites will likely drop to IFR occasionally in light
SHORT TERM: IFR conditions are likely Friday evening.
Conditions should then improve to MVFR then VFR from north to
south late Friday night into Saturday morning. VFR conditions
are expected across the area Saturday afternoon through Sunday.
Conditions should lower to MVFR or IFR Downeast Sunday night
then be IFR across the area on Monday in low clouds and some
NEAR TERM: A Small Craft Advisory remains in effect through midnight
tonight. Winds and seas will slowly subside this evening and will
drop below 25 kt and 5 ft, respectively, by midnight as high
pressure crests over the waters. However, once the high moves to the
east, winds and seas will build once again on Friday, reaching SCA
levels early Friday afternoon. Additional headlines will likely be
SHORT TERM: A SCA may be needed Friday evening for
southwesterly winds gusting up to 25kt. Winds should be below
SCA late Friday night through Saturday then may reach SCA again
Saturday evening in gusts up to 25kt. Winds should be below SCA
Sunday into morning as high pressure crest over the area. Winds
may increase to SCA Monday afternoon into Monday night ahead of
approaching low pressure.
The high temperature this afternoon of 21F at Caribou, ties with
2008 for the lowest high temperature ever observed at Caribou on
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ050>052.