Area Forecast Discussion
Issued by NWS Caribou, ME
FXUS61 KCAR 241011
Area Forecast Discussion
National Weather Service Caribou ME
611 AM EDT Mon Apr 24 2017
A cold front moving off the Downeast coast this morning will
dissipate today. High pressure will build across the area
tonight into Tuesday. Low pressure will slowly move up the coast
Wednesday into Thursday.
.NEAR TERM /THROUGH TONIGHT/...
6:11 AM Update...The main challenge early this morning is the
cloud cover. Early morning visible satellite pictures show areas
to the north of Caribou are mainly clear, but areas of low
cloud remain to the south of Caribou to the Katahdin Region,
with mostly high cloud across the Downeast region with some
patchy fog along the coast. Other than some minor tweaks to the
hourly conditions early this morning no other changes are
planned at this time.
A cold front is pushing off the Downeast coast early this
morning, and will stall out and dissipate across the coastal
waters today. The brunt of the cold air mass slides from central
Quebec and into Newfoundland, but it does clip northern Maine
with 850H temps of around -10C across the Saint John Valley, but
closer to +2C along the Hancock County coast. This will lead to
a sharp north to south temperature gradient with highs not
getting much above 40 degrees in the saint John Valley, but
closer to 60 degrees across the interior Downeast region. The
sky will be partly to mostly sunny with some cu to pop up across
the north in the colder air. Tonight will be mainly clear and
cold as high pressure settles into the area. Lows will range
from the 20s across the Crown to the 30s toward the coast. Some
of the broad northwest valley may drop into the teens.
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
Wet and cloudy weather pattern setting up Tuesday night and
persisting for quite a while. Long moist southerly fetch setting
up for Wednesday/Thursday with precipitable water values around
record high levels for so early in the season. Went with close
to 100 percent chance of rain most areas late Tuesday night
through Wednesday night. At least Tuesday day looks generally
dry...enjoy it while it lasts as rain is on the way. Airmass
aloft is quite warm, but with moist low level southerly flow
off the cool Gulf of Maine, don`t anticipate it being that warm
at the surface. At least it will be warm enough for precipitation
to safely be all rain.
Models all have the deep moisture over the region with the very
high precipitable water values, but overall not too concerned
about flooding for a few reasons. First, expect precipitation
rates not to be conducive to flash flooding, with little if any
in the way of convection and more of a stratiform rain. Second,
although rivers are running high, they are running highest in
the north, but the best chance for heaviest rain totals from 1.5
to 2.5 inches is Downeast where rivers aren`t running as high.
Third, upper level dynamics are fairly weak and will limit the
ability of the high precipitable water values to translate into
that heavy of rainfall. Fourth, MMEFS ensemble river guidance
indicates that even with the high end of rain occurring, most
rivers should be able to handle the potential couple inches of
rain. Still, will need to keep an eye on things.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Wet and unsettled continuing into late week. Deepest moisture
moves off to our east Thursday and Friday, but still a chance of
rain due to persisting low level moisture. Perhaps a bit of a
break in the action late Saturday to early Sunday before the
next likely rainmaker moves in late Sunday into Monday.
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
NEAR TERM: A few patches of IFR ceilings early this morning
along the coast along with patchy fog will give way to VFR
by 12-13Z. MVFR-IFR in spots across northern Maine to the south
of KPQI will give way to VFR by 13Z. VFR for the remainder of
the day and through tonight.
VFR Tuesday, but deteriorating to predominant IFR areawide
Tuesday night, persisting into Wednesday night with rain and low
ceilings. Expect general MVFR Thursday and Friday.
NEAR TERM: The wind and seas will remain below small craft advisory
levels through tonight.
SHORT TERM: Small craft conditions likely Tuesday night and
persisting for several days after. With a long southerly fetch,
seas will build to around 9 feet Wednesday and Thursday. May be
minor coastal erosion around the high tide Wednesday night.
Something to watch, but not overly concerned at this point.