Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
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FXUS61 KCAR 231200
Area Forecast Discussion
National Weather Service Caribou ME
700 AM EST Thu Feb 23 2017
Low pressure will move through Quebec today bringing a cold
front through the region tonight. High pressure will return on
Friday. A warm front will cross the region Friday night.
.NEAR TERM /THROUGH TONIGHT/...
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Temps drop a bit more early this morning w/upper teens in some
of the low spots of the northern and western locales. Some
freezing fog still around w/some icy spots on roads possible
this morning. Upgraded the fog across the downeast to areas this
morning. Reports of vsby down to <1/4 of a mile. Expecting
improving conditions later this morning w/the warming trend and
s winds kicking in. Radar trends showing some returns showing
across across far northern areas of Aroostook County this
morning ahead of the warm front. Still expecting some light snow
or even sleet/freezing for a brief period across the far n and w
as the warm front lifts n. Not expecting much accumulation
w/this batch of precip.
Another mild day in store w/more melting.
Temps in some areas this morning dropped below 20F such PQI and
MLT. Looks like temps across just about the entire CWA down
below 32F w/some fog around. Latest IR satl imagery showed
clouds advancing ahead of a warm front lifting across the region
this morning. Radar showed returns back across Quebec pushing
ene. The latest HRRR and RAP lining up well w/bringing an area
of precip across far northern and western areas this morning.
Temps being below 32F will leading to the potential for some
freezing rain/drizzle or even sleet for a brief period mainly
across the north and west. Further s, conditions should remain
dry. Not expecting much in the way of icing as temps should warm
fairly quickly and be well above 32F by mid morning. Temps will
continue to warm into the afternoon as the region gets into the
warm sector. We are talking afternoon temps shooting well into
the 40s and even lower 50s in central and downeast locations.
Dewpoints going above 32F will lead to a melting of the
The main action of precip will arrive later this afternoon into
the evening w/the apchg cold front. There does appear to be a
pre-frontal trof to set up ahead of the front. Mdl sounding
data from the NAM & RAP support the potential for some squalls
in the form of heavy rain showers and winds gusts of 30+ mph.
Strong llvl shear of 35+ kts along w/steep lapse rates in the
low and mid level lend support for the squalls. Another thing to
note was the elevated CAPE of 120+ joules on the NAM across the
northern areas which would help to support the squall potential.
There is even concern about some isolated tstms. Lightning
detection showed some activity across Lake Huron and this
activity was moving ne. Will look at this potential again later
this morning w/the update.
The cold front is forecast to slide across the CWA tonight
w/showers pushing off to the e. A slight cooling is expected
overnight w/some clearing as temps fall back into the upper 20s
and lower 30s across the n and w. Central and downeast areas
will see mid 30s. Winds will pick up some later in the evening
but show signs of letting up by early Friday morning. This will
allow for fog development w/wet surface. Decided to add the
mention of fog in the forecast.
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.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
A weak cold front is expected to be through the area by Friday
morning with the area in a col. The front will tend to lift back
northward as a warm front later in the day while a cold high in
Quebec subtly wedges into northern Maine. This will bring enough
low level cold air for a freezing rain and sleet event north of
Houlton on Friday night. A tenth of an inch of ice is
possible...mixed with sleet. Rain will occur further south as
the warm front moves northward. On Saturday, the entire area
will be in the warm sector with a moist south to southeasterly
flow. Expect this will cause widespread low clouds, fog, drizzle
and rain Saturday and Saturday night...especially in upslope
areas in Piscataquis and northern Penobscot counties. The cold
front will cross Saturday night with rainfall amounts around a
quarter to a half inch. Locally heavier amounts are possible due
to instability aloft. The amount of rain by itself is not
expected to cause significant hydro issues, but the long period
of mild temperatures from now through the cold frontal passage
will be an issue. Most areas in the southern half of the
forecast area will be above freezing from now until Sunday
night. Dew points will reach well into the 40s later Saturday
into Saturday night ahead of the cold front. Rivers will have to
watched for ice movement by Saturday night into Sunday with the
threat of ice jams. The rain will change to snow later Saturday
night for a brief time in the northern half of the area with no
significant accumulations expected.
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Temperatures will remain relatively mild on Sunday with highs in
the upper 30s north and low to mid 40s for Bangor and the Down
East region. Besides potential river issues, winds will be
notable on Sunday with gusts over 30 mph in a well-mixed
boundary layer. Cooler air finally arrives for Sunday night to
slow the melting. For early next week, daytime temperatures will
be above freezing, but nighttime temperatures will drop well
below freezing with low dew points. This will slow snow melt to
a much more manageable level. Did go below guidance on Monday
night as the high builds over the area. By Wednesday, the next
significant low pressure system will be moving into the area. At
this time, have played for a storm track to the north of the
area...meaning snow changing to rain as far north as northern
Aroostook County...but it`s still too early for high confidence.
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
NEAR TERM: MVFR vsbys w/fog this morning across portions of the
northern sector such as KCAR while IFR vsbys for some downeast
sites which includes KBHB. KBGR was seeing fog starting to
develop. Conditions are expected to drop back to MVFR and even
IFR today into the evening. LLWS will be a concern later this
afternoon into the evening mainly across the northern terminals
w/the cold fropa. Fog potential is there once again overnight
leading to IFR/MVFR vsbys.
SHORT TERM: For Friday, some MVFR cigs are possible with good
vis. On Friday night, IFR cigs will move into the area with some
freezing rain and sleet north of HUL. IFR cigs and vis will
continue to be the predominant condition Saturday into Saturday
night with fog, rain and drizzle. VFR tempo MVFR cigs return
Sunday into Monday. Strong west winds will gust over 30 mph on
Sunday into Sunday evening. Tempo IFR vis in snow showers will
be a threat on Monday north of HUL.
NEAR TERM: Decided to hoist the SCA for the outer zones for this
afternoon into tonight mainly for gusts to hit 25+ kts ahead of
the apchg cold front. There is a 35-40 kt jetstreak that is
forecast to move across the region aiding in the stronger winds
gusts. The winds are expected to drop off after 1 am w/the front
clearing the region. Seas will be at 2-4 ft.
SHORT TERM: There is a possibility of an SCA Saturday night, but
confidence is not high as it will be very stable and have fog in
the forecast for Saturday into Saturday night. It is much more
likely to have an SCA from Sunday into Monday. Marginal gale
winds are possible Sunday afternoon.
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MARINE...Small Craft Advisory from 4 PM this afternoon to 2 AM EST
Friday for ANZ050-051.
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