NWS Caribou, Maine Area Forecast Discussion

FXUS61 KCAR 230532

Area Forecast Discussion
National Weather Service Caribou ME
132 AM EDT Mon Sep 23 2019

High pressure will continue to move south of the region overnight.
Low pressure will approach Monday and slowly cross northern
Maine through Wednesday morning. High pressure will build over
the area Wednesday evening. A cold front will approach and cross
the area on Thursday followed by high pressure on Friday.


130 am update...
Showers are vry slowly working their way east twd nwrn
Aroostook cnty but hv had to delay pops by 1-2 hrs more with
this update. No other chgs needed at this time.

Previous Forecast...
A southwest flow will be in place across the region tonight
between an approaching cold front from the northwest and high
pressure off the mid-atlantic. The southwest breeze and
increasing cloud cover will keep low temperatures generally in
the low to mid 60s across the region. A few showers are expected
to develop across far northern areas overnight, especially
toward the St.John Valley nearer to the approaching cold front.
The cold front will slowly move south across Northern areas on
Monday. Expect mainly cloudy skies and a chance for showers
across northern and central areas on Monday. Across central and
downeast areas, expect a partly sunny start followed by
increasing afternoon clouds along with scattered showers and
perhaps an isolated afternoon thunderstorm. Highs on Monday
across the north will still be above normal but not as warm as
today, with generally low to mid 70s expected. Across central
and downeast areas, highs will be near 80 degrees but a little
cooler near the coast.


By Mon ngt, an upper low crossing E across QB prov will be close
enough to result in weak secondary sfc cyclogenesis ovr Downeast,
with banding of shwrs movg W to E into our FA, and then SW to
NE across our FA on Tue. Depending on where the banding with
isolated thunder occurs (which looks msly Cntrl and Downeast
attm) and longevity ovr ptns of the FA, there is the potential
of sig to lcly hvy rnfl late Mon ngt thru Tue eve, but for now,
given the uncertainty of these factors, we went middle of the
road for fcst 6 hrly QPF values for our Rgn thru this tm frame
with max 90+ percent PoPs. Lgtr rnfl will cont late Tue ngt
with shwrs becoming sct Wed morn as both sfc and upper low move
E across the Can Maritimes, then ending Wed aftn. Temps will be
cooler both Tue and Wed, spcly N and Cntrl areas with mild
ovrngt lows.


Our FA will receive a brief respite between system Wed eve into
ovrngt before cldnss increases ahead of the next s/wv trof apchg
from Cntrl Can late Wed ngt. Shwrs will then move into the FA by
Thu ahead of the cold front associated with the s/wv as the s/wv
moves msly N of our Rgn. Subsequently, the best event rnfl
potential of a quarter to half inch will likely be experienced
across the N where we weight the highest PoPs in the likely
range with both lower PoPs and QPF Cntrl and Downeast areas.
Shwrs end behind the cold front late Thu ngt, resulting in the
return of fair, breezy and dry erly fall like wx for Fri and Sat
as sfc hi pres from the great lks builds toward and crests the
Rgn with the slower 12z ECMWF favored ovr the faster 00z GFS
model solution for dry conditions Sat.


NEAR TERM: VFR will lower to MVFR around or shortly after 12z at
FVE, CAR and PQI in cigs and -shra. LLWS will be present through
this time as well and wl extend as far south as HUL. Cannot rule
out brief IFR cigs this afternoon north of HUL but restrictions
will predominantly be MVFR. Downeast terminals will remain VFR
until late in TAF period with MVFR -shra expected after 02z. SSW
at all terminals from 10-15kts today with northerly sites become
light fm the north after 00z.

SHORT TO LONG TERM: Mon ngt thru Tue Ngt - IFR clgs/vsbys all
TAF sites mainly in shwrs/rn with patchy late ngt fog Downeast
sites late Mon ngt/early Tue morn. Lgt winds.

Wed - MVFR clgs all TAF sites improving to VFR Wed aftn. Lgt

Wed ngt - All sites VFR. Lgt winds.

Thu thru Thu ngt - All sites MVFR clgs/vsbys in shwrs. Lgt

Fri - All sites VFR. Breezy NW winds.


NEAR TERM: A Small Craft Advisory is being issued beginning
around daybreak Monday and continuing through Monday afternoon
for the outer waters. Winds/seas are expected to slowly increase
overnight. On Monday expectd gusts to around 25 KT and seas 4 to
7 feet.

SHORT TO LONG TERM: Initially SCA conditions outer MZs mainly
for seas Mon ngt, subsiding below SCA by Tue morn, then cont`d
no hdlns for the remainder of the fcst. Went with about 90
percent blend of WW3/NWPS wv ht guidance for fcst wv hts,
compromised of two spectral wv pd groups; a short fetch 6 to 8
sec group and an open Atlc long pd swell group of 12 sec.


MARINE...Small Craft Advisory from 8 AM this morning to 5 AM EDT
     Tuesday for ANZ050-051.



Near Term...Duda/Farrar
Short Term...VJN
Long Term...VJN

NWS CAR Office Area Forecast Discussion