Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
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FXUS61 KCAR 270243
Area Forecast Discussion
National Weather Service Caribou ME
1043 PM EDT Sun Mar 26 2017
High pressure will move east of the area tonight as low pressure
approaches from the Great Lakes. Low pressure will cross the area
Monday into Tuesday.
.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --1035 PM Update...
Made some adjustments to the pops to bring percentages up across
the southern sections such as sw Piscataquis County and southern
Penobscot County. 00Z UA showed high pres ridge axis still well
w of the region w/dry air in place. Satl imagery showed
mid/high clouds across the north while clouds deck was lowering
this evening. Latest radar trends showing returns showing up
across the western section edging ene. Most of the activity was
aloft as llvls very dry. The latest run of the HRRR mesoscale
model doing well w/the precip placement. A frontal boundary was
in place across the region and radar returns were lining up
along this boundary per the 00z sfc analysis. Temps look like
they are going to be warmer than previously forecast and
adjustments were made to bring them overnight. Will monitor
the coast as some freezing precip is possible during the morning
hrs before going over to rain in the afternoon.
Mainly clear skies this evening will give way to increasing
clouds tonight in advance of an approaching warm front. The air
mass across the region is very dry with dew points down around
zero across most of the region as of mid afternoon. The very low
dew points and light winds will allow for some radiational
cooling this evening before clouds thicken up after midnight.
The coldest reading are likely to be across far northeast
Aroostook County and the St John Valley where lows are expected
to fall into the single digits above zero before clouds thicken
later tonight. With the very dry low level air in place, it will
also take a while for precipitation to reach the ground, so not
expecting precipitation to develop until well after midnight
across the west and probably not until around or a bit after day
break across Northeast Aroostook and the St John Valley.
Overrunning precipitation will continue overspread the region
early Monday. Across the north the precipitation should remain
mainly snow much of the day. Across central and interior
downeast areas, expect snow to mix with sleet and freezing rain
by afternoon. Across the downeast coast, expect a brief period
of mixed precipitation in the morning to transition to plain
rain by afternoon. A weak area of low pressure developing along
the front to our south will cross the gulf of Maine during
Monday afternoon, keeping the low level cold air in place. Thus,
have leaned with cooler mos numbers for highs on Monday. Winter
Weather advisories have been issued for all of Northern Maine
for Monday. With the low level cold air expected to hang tough
into the afternoon, have also included the Penobscot region and
greater Bangor region, as well as all of interior downeast in
the Winter Weather Advisory. There could be a mix even along the
downeast coast into Monday morning, but thinking there may be
enough warming for a transition to all rain by afternoon, thus
have not included in the advisory at time. Highs on Monday are
expected to range from the upper 20s across the north to the low
to mid 30s along the coast.
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.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
A large but poorly organized storm system will be moving into the
area Monday evening with one low center along the coast and another
to our west. Temperatures Monday evening will be warm enough for
some light rain and drizzle Downeast. A mix of snow, sleet and
freezing rain is likely across the north with all snow possible
across the far north near the St. John Valley. Precipitation will
generally be light, and will diminish late at night as one low
center near the coast moves east and another remains back across
Quebec. As the Quebec low crosses the area on Tuesday, some rain
showers will be scattered over the region. Any showers may be mixed
with some sleet or snow pellets across the far north with little or
no accumulation expected. Some light rain, and snow showers across
the north, may continue into Tuesday night as a weak occlusion
crosses the area. Drier air should then begin moving into the region
on Wednesday. However, low pressure consolidating south of Nova
Scotia will have an inverted trough extending back across New
Brunswick on Wednesday. If this inverted trough sets up further
west, some scattered rain and snow showers could be possible. For
now, will only have sight chance of snow or rain showers on
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Low pressure will move away to the east Wednesday night into
Thursday as gusty northwesterly winds follow. The air will only be
moderately cooler with highs Thursday expected to be in the 30s
north and 40s Downeast. High pressure will then build over the area
Friday into Saturday bringing plenty of sunshine. Low pressure will
be tracking off the Mid-Atlantic coast on Saturday, but should track
far enough south to miss our area. Generally dry and mild weather is
then expected late next weekend as upper level ridging along the
east coast combined with low pressure over central Canada brings a
southwesterly flow across the area.
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
NEAR TERM: VFR through most of tonight. Conditions will deteriorate
to MVFR 09z to 12z, then to IFR in a wintry mix on Monday at
SHORT TERM: IFR conditions in low clouds and snow and rain are
expected Monday night through Tuesday. IFR conditions Tuesday
evening may improve to MVFR late at night, then VFR on
Wednesday. VFR conditions are likely on Thursday as high
pressure approaches. VFR conditions in high pressure are
expected on Friday.
NEAR TERM: Winds/seas will remain below small craft advisory
levels tonight. Winds/seas will begin to increase to small craft
advisory levels by late Monday afternoon. Visibilities will
decrease to 1 to 3 nm in precipitation late tonight through
SHORT TERM: A SCA will be needed Monday evening for
southeasterly winds gusting up to 30 kt ahead of approaching low
pressure. Winds will diminish late Monday night into Tuesday.
Some fog may limit visibilities late Monday night into Tuesday
as surface low pressure crosses the waters.
ME...Winter Weather Advisory from 5 AM to 10 PM EDT Monday for
MARINE...Small Craft Advisory from 10 PM Monday to 3 AM EDT Tuesday for