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000 
FXUS61 KCAR 141105
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
605 AM EST Sat Dec 14 2019

.SYNOPSIS...
Intensifying low pressure will track northward across New 
England to northern Maine today through tonight. A cold front 
will cross the region Sunday. High pressure will cross the 
region Monday. Low pressure will cross the Gulf of Maine 
Tuesday and exit to the east by Tuesday night. The low will exit
through the Canadian Maritimes on Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
6 am Update...
Latest radar reflectivity imagery shows rain continuing to 
expand northward across the region. Temperatures at this hour 
have warmed above freezing across the region, with the 
exception of the St John Valley, where temperatures were still 
hovering in the upper 20s to lower 30s. Only minor changes to
ingest latest observations, otherwise no other changes to going
forecast. 

previous discussion
Low pressure from the mid atlantic states will continue to lift
north toward the region today. This system will bring rain to 
the region today. Deep layered southerly flow will transport 
abundant moisture northward across the region resulting in the 
possibility of locally heavy rainfall. The heaviest rainfall is
expected to be across Downeast areas, where rainfall amounts of
2 inches or greater are expected. Elsewhere, widespread 
rainfall amounts of 1 to 2 inches are expected across the 
region.

The locally heavy rainfall will result in the possibility of
localized ponding of water on area roadways, although not 
expecting any widespread flood issues. Winds may gust as high as
35 to 40 mph along the downeast coast later this morning and 
into this afternoon in response to a low level jet traversing
the region. 

Highs today will be well above normal for this time of year,
with low to mid 40s across the north and upper 40s to lower 50s
across downeast areas.

Rain will continue into this evening as low pressure lifts to
the northwest of the state. The rain will taper to showers 
after midnight as it continues to track to the north of the 
region. Colder air will begin to filter into the area toward 
daybreak Sunday. This will result in any rain transitioning to 
snow showers across western areas but little in the way of 
accumulation is expected. Lows tonight are expected to range 
from the low to mid 30s across the north Maine Woods to the 
lower 40s across Downeast areas.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
Strong winds expected Sunday into Sunday night.

Intensifying Low pres lifts up through Quebec w/cold air expected to pour 
into the region during the day. Temps will be the warmest in the morning 
w/early high temps in the 40s, and then temps will fall back by late morning. 
An upper trof will be moving through the region which will aid 
in some snow showers/flurries across the n and w. The pres 
gradient will tighten /strong wind potential hitting Sunday 
afternoon into Sunday night. SSW winds will veer to the W during
the day. GFS and NAM soundings show inverted V in the llvls w/ 
dry air aloft. Momentum transfer from both of this set of 
guidance support wind gust potential of 40-50 mph. Some power 
outages are possible. Wind headlines may be needed for Sunday 
afternoon into Sunday night. Gusty W winds will continue through
Sunday night w/gusts at time at least around 45 mph. Temps 
continue to plummet Sunday night w/temps hitting the single 
numbers across the far n and w, while central and downeast 
areas see mid/upper teens. Quite a change from 24 hrs ago.

Monday will continue to see gusty winds, but the pres gradient will be 
loosening during the day as the low continues it's track through Labrador.
It will be a sunny day but cold w/daytime temps below normal.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
High pres will move across the state Monday night. Clear skies and 
light winds w/a cold airmass in place. The long range guidance 
including the ECMWF and GFS show some weak WAA aloft. This 
setup would be ideal for a llvl inversion to setup, keeping cold
air trapped at the sfc. Decided to lean in this direction and 
go below the guidance for overnight low temps, especially across
the nw and w where there is still a decent snow cover. Some 
sites such as Estcourt Station and Clayton Lake could see 
readings down around 0F by Tuesday morning. 

Low pres tracking up from the TN Valley is forecast to move into the 
southern Gulf of Maine Tuesday into Tuesday night. The GFS and 
its Ensemble Mean support this track as does the ECMWF and a 
number of its ensemble members. This track brings the potential 
for some accumulating snow across the coastal region. Confidence
is high enough to bring 60-70% chance for snow to this region 
and 40-50% chance for snow into the Bangor and Calais region. 
Further n, snow chances drop off w/the northern 1/2 of Aroostook
County staying dry. Confidence is low attm on snowfall amounts 
as there is some discrepancy w/the long range guidance in this 
regard. The GFS is the most aggressive w/the amounts as the 
ECMWF and a good number of its ensembles show lesser amounts 
w/the best forcing off the coast. The Canadian Global is also 
lower w/the amounts. The low looks to be a fast mover and is 
shown to be east of the region by late Tuesday night w/skies 
clearing out. An upper low w/its sfc front is shown by the long 
range guidance to swing across the region Wednesday afternoon 
into Wednesday night. The big factor is the very cold air behind
this trof that is forecast to pour into the region Wednesday 
night into Thursday. Enough forcing looks to be associated 
w/this feature to set off some snow showers into Thursday. 
Interestingly enough, the GFS shows a norlun type setup w/the 
upper low moving across southern Maine. This setup could favor a
round of snow for portions of the Downeast. The ECWMF however 
has the upper low further n supporting snow showers. Confidence 
is low and decided on 20-30% chance of snow showers. Temps 
Wednesday and Thursday are expected to continue to run below 
normal. Winds look like they could crank up as the gradient 
tightens in the wake of the upper low for Thursday into Friday.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: Widespread IFR/LIFR conditions are expected to
persist today and tonight in rain. Low level wind shear will
also be an issue into tonight at all the terminals.

SHORT TERM: 
Sunday: IFR To MVFR north. MVFR to VFR for BGR and BHB. Strong
gusty SW to W winds with gust potential to 40+ kts. 

Sunday night: Possible MVFR across the northern terminals 
early, otherwise VFR. Strong gusty W winds continue. 

Monday: VFR: Gusty west winds look like they will start to drop
off by later in the afternoon.

Monday night: VFR, lowering to MVFR then IFR in snow Downeast. W 
winds becoming light then E late. 

Tuesday: IFR in snow for KBGR and KBHB Tuesday and then becoming
MVFR by Tuesday night. KHUL may see IFR/MVFR for a time later
Tuesday into Tuesday evening. North of KHUL, VFR expected. NE 
winds becoming N then NW at 10 kts.

Wednesday... Possible MVFR and perhaps IFR in snow for KBGR and
KBHB. Across the northern terminals, VFR w/periods of MVFR in
some snow showers.

&&

.MARINE...
NEAR TERM: A Gale Warning has been issued beginning this morning
and continuing through tonight. Visibility will be reduced to 1
NM or less at times in rain into this evening.

SHORT TERM: Gale Warning to continue right into early Monday.
Expecting sustained winds of 25-35 kts w/gusts to 45 kts Sunday
into Sunday night. Winds will be dropping off on Monday at 
20-25 kt, but some gusts of 35 kt still possible through 12 PM.
Seas of 14-15 kts Sunday will be subsiding to 6-7 ft by Monday
afternoon.  

Monday night into Wednesday...Winds drop off to 10 kts w/seas 
dropping below 4 ft by Tuesday morning. Low pres passing across 
the southern portion of the Gulf of Maine w/winds back to the NE
10-20 kts. Seas are expected to pick back up to around 6 ft by 
Tuesday night into early Wednesday. Winds will become NW w/this
component helping to knock back the seas to below 6 ft by later
in the day on Wednesday.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Gale Warning until 1 PM EST Monday for ANZ050>052.

&&

$$

Near Term...Duda

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