Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
1023 PM EDT Sat Jul 4 2015
a weak cold front will approach the region from Quebec tonight...
then will cross the region through Sunday with a chance of showers
and possible thunderstorms. High pressure and warmer temperatures
returns behind the front for Monday...with more humid conditions
on Tuesday as high pressure builds across the Middle Atlantic States
and then moves east into the open Atlantic.
Near term /through Sunday/...
1020 PM update...
showers are weakening as they head east through New Hampshire and not expecting
precipitation to survive into western County Warning Area thus have rmvd mention of isolated showers
drg the overnight. Have lowered min temperatures across North Woods as they are
dropping quicker than expected. No other changes needed to existing
Previous discussion below...
Precipitation chances will increase overnight as a cold
front/trough of low pressure approaches from the west. Still
believe that the rest of this afternoon and evening will be dry
just about everywhere. However, the latest hrrr/rap are indicating
some isolated showers developing across the higher terrain of
western Maine and moving into our western areas toward evening.
Have therefore introduced a slight chance of showers for these
areas this evening. Otherwise, don't expect much more than a few
sprinkles for our southern areas. The main chances for rain really
arrive later tonight as the front gets close to our western
border. Lows will be in the middle 50s just about everywhere.
The front makes its push across the region on Sunday. Moisture
isn't all that impressive, so don't expect much more than
scattered coverage for showers. Sbcapes are prognosticated to reach into
the 400-800 j/kg range, enough for scattered thunderstorms. Weak
shear means any convection will be run of the mill. Temperatures
range from the middle 70s in the northwest and along the coast to
around 80 for interior downeast.
Short term /Sunday night through Tuesday/...
sun evening should begin with The Retreat of any remaining showers over
western portions of our forecast area as a weak cold front and associated upper trough
moves well east of the region through the eastern Maritimes. Otherwise...
clearing skies are expeceted over the forecast area overnight sun with light winds and near
seasonal low temperatures as surface hi pressure builds from the west.
With surface hi pressure anchoring over the northern Middle Atlantic States and
adjacent portions of the Atlantic Ocean on Monday as a moderately strong upper level
ridge builds over northern new eng...skies will be sunny with light west-southwest
winds. Temperatures should respond strongly reaching highs Monday afternoon sig
above 80 degree f over all xcpt immediate downeast coast portions of the
forecast area...the warmest since late may.
Monday evening will be fair and summerlike with relatively warm conditions
and a light breeze. Tuesday will begin msly sunny...then clouds will
increase from the west-southwest later in the day as a lead shortwave from the
upper Great Lakes and S central can begin to approach...bringing with it
increasing humidity as south-southwest winds increase and late afternoon scattered showers/
thunderstorms to msly the northwest third of the forecast area. The arrival tmg of
showers/thunderstorms to the northwest was based on splitting the difference
between the faster GFS and slower European model (ecmwf) solutions...although we
did note that the 12z dtmnstc GFS was slower than its previous runs.
Hi temperatures Tuesday afternoon will remain very warm across the north and west with
the increase in humidity...but will likely be a little cooler over
downeast areas with gradient south-southwest winds allowing marine cooled air
to work further inland than Monday afternoon.
Long term /Tuesday night through Saturday/...
a cold front sweeps across northern New England on Wednesday for
a chance of showers and thunderstorms. The front is progressive...
therefore quantitative precipitation forecast should be less than one quarter of an inch...except
near stronger storms.
A weak zonal flow aloft sets up behind the front with slightly above
normal temperatures and little or no precipitation.
Aviation /02z Sunday through Thursday/...
near term: VFR at all terminals next 24 hours. May see a shower
early afternoon Sunday with no restrictions expected at this time.
Potential exists for -tsra and also MVFR conditions but confidence
is too low to include mention in terminal forecasts.
Short term: VFR conditions should prevail across all of the taf
sites Sun night through Tuesday.
near term: no headlines are anticipated through the weekend. High
pressure will cross the waters tonight into Sunday morning,
followed by a frontal boundary Sunday afternoon. This will bring
showers and possible thunderstorms to the region. Winds and waves
will remain below small craft levels.
Short term: no hdlns anticipated over our waters. Waves begin at 3
to 5 feet over the outer waters Sun night with left over swell then
diminish Monday and Monday evening. Winds and seas increase some to 10 to 20
knots and 2 to 4 feet respectively by Tuesday afternoon with a return flow SW
wind...but still below min Small Craft Advisory criteria based on latest wind and WV