Scientific Forecaster Discussion
fxus61 kcar 200125
Area forecast discussion
National Weather Service Caribou ME
925 PM EDT Thu Sep 19 2019
high pressure will remain across the region through the weekend.
A cold front will cross the area late Monday. High pressure will
begin to build back into the region on Tuesday.
Near term /through Friday/...
9:25 PM update: the 00z kcar sounding showed significant
warming in the low and mid levels during the past 24 hours. The
low level air mass is also not as dry with dew points mostly in
the 40s this evening, compared to the 30s last evening at this
time. There are some high clouds pushing east along the western
Maine/Quebec border, but at this time just expecting some thin
cirrus. Lows tonight will mostly be in the 40s across the forecast area
with the coolest temperatures likely in the sheltered valleys
across the eastern zones where a few spots may drop into the
upper 30s. Made a few minor tweaks, mainly to the hourly temp
grids to lower across the valleys.
the cool high pressure system which has been over the area will
begin to slowly slide south of the region overnight. A light
westerly return flow behind the high will set in overnight. Some
moisture circulating in behind the high and ahead of a weak
trough dropping in from the northwest may bring some patchy
clouds to northern areas late tonight. Temperatures will not be
as cold as recent nights, bottoming out in the 40s in most
areas. A return westerly flow will continue on Friday with a
partly to mostly sunny sky. Strong ridging and warm air
circulating in behind the high will make Friday the warmest day
so far this month for many areas. Highs will be in the mid 70s
in most inland locations.
Swell from Hurricane Humberto will begin to reach the coast
Friday with waves up to 4 to 7 feet expected along the downeast
coast. The highest waves are likely along the Hancock County
coast, with seas not as high along the Washington County coast
as a result of Nova Scotia shadowing eastern downeast area.
Short term /Friday night through Sunday/...
high pressure will dominate the weather through the near term
period of the forecast. A frontal system over the Great Plains
will move east and by the end of the period will be just west of
Maine extending northeast to southwest across Quebec. Sunny
days and mild temperatures will continue through the end of the
Loaded a blend of the GFS/NAM/ECMWF/Gem to smooth out the minor
differences in the models.
Long term /Sunday night through Thursday/...
high pressure will build southeast of the area as a cold front
moves towards the area. Monday morning the front will move into
northwest Maine bringing rainshowers to the area. The front will move
into the Gulf of Maine early Tuesday morning. Wrap around
precipitation will affect northern Maine Tuesday into early
Wednesday morning. Higher pressure will build across the area
Wednesday. Another low and associated frontal system will push
into western Maine early Thursday morning bringing another round
of showers to the area. The front will move east by the end of
the period. Temperatures will be a bit above normal at the start
of the period, but will fall a bit to near normal after the
front on Tuesday.
Loaded a blend of models to smooth out the minor differences.
Aviation /01z Friday through Tuesday/...
Thursday night and friday: VFR across the area. Light and
variable winds this evening becoming light westerly late tonight
Friday night through Tuesday...high pressure will dominate the
weather through Sunday evening. VFR conditions all sites, except
for IFR in morning fog in the vicinity bodies of water.
Increasing clouds Sunday afternoon.
Sunday night through Monday morning...increasing clouds
decreasing ceilings becoming MVFR Monday morning in shower.
Monday morning through Tuesday...low MVFR in showers. The front
will move into the Gulf of Maine early Tuesday morning.
Conditions improving to MVFR with a few lingering showers
near term: winds and seas are expected to be below Small Craft Advisory tonight
into early Friday morning. Swell from Hurricane Humberto will
increase through the morning and midday on Friday requiring a
Small Craft Advisory for hazardous seas from mid morning Friday through Friday
Short term: elevated seas from a southerly swell as Humberto
passing well south of the coastal waters. Seas above 5 ft in a
southerly swell will continue Friday night into Saturday
morning. Seas will subside below 5 ft Saturday morning. Winds
will remain below Small Craft Advisory through the period.
long period southeast swell from Hurricane Humberto in the open
Atlantic will produce high surf for coastal Hancock and
Washington counties Friday into early Saturday. Wave heights
will increase to 4 to 7 feet during the late morning hours
Friday and continue into early Saturday. The combination of
high surf and long swell will create dangerous rip currents.
Astro tides are nearing Low Point of month, with no overwash
expected. Conditions will begin to improve after midnight.
ME...high surf advisory from 10 am Friday to 2 am EDT Saturday for
Marine...Small Craft Advisory for hazardous seas from 10 am Friday to 2
am EDT Saturday for anz050>052.