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Area forecast discussion 
National Weather Service Gray ME
1009 am EDT sun Jul 13 2014

Synopsis...
a warm front will push northeast of the region today allowing for
very warm...humid and unstable air to invade the region today
through Monday. This will set the stage for showers and
thunderstorms to develop later today and continue tonight and
Monday. Some of the thunderstorms could produce gusty winds, small
hail and heavy rain. A cold front will move to the coast Tuesday
and stall resulting in scattered showers and thunderstorms through
middle week before high pressure moves in Thursday and pushes the
front to the east. High pressure will build over the region
through Saturday.

&&

Near term /until 6 PM this evening/...
10 am update: previous forecast has a good handle on situation and timing
for this afternoon and evening. Input latest observation data and only
minor tweaks were needed.

Previous disc:
the warm fnt pushes to the NE of the forecast area early toady. This
brings in very warm...humid and unstable air for today. This will
allow rain showers/thunderstorms to develop...first over the north/Mt/far western zones
where instability increases first as indicated by cape...Li and
850 mb Theta-E values...then spreading to the east and southeast later
today. Some thunderstorms could have gusty winds...small hail and heavy
rain in favorably sheared environment as indicated by increasing
and veering winds from surface to 700 mb.

Winds pick up today from the S SW which brings in cooler air off
the ocean for coastal zones...then spreads further inland over southern
and central Maine. This will hold back temperatures today. Also...the
increasing clouds then developing convection will hold back temperatures
across the forecast area. Look for highs mainly in the 70s north/Montana and
coastal zones and mainly 80 to 85 elsewhere. If clouds hold off
longer allowing for more sunshine then inland temperatures could rise a
bit higher.

&&

Short term /6 PM this evening through 6 PM Monday/...
rain showers/thunderstorms continue at least into this evening then let up overnight.
Areas of f likely to form in the warm and muggy air mass...
especially in areas that had rain during the afternoon and/or
evening. Min temperatures will be mostly in the 60s.

The very warm...humid and unstable air mass remains over the
region on Monday as a trough of low pressure moves through. The
instability covers just about the entire forecast area as indicated
by forecast cape...Li and 850 mb Theta-E values. Thus expect
rain showers/thunderstorms across the forecast area...again with the potential for
gusty winds...small hail and heavy rain with any thunderstorms with
favorably sheared environment as indicated by fairly strong and
veering winds from surface to 700 mb.

&&

Long term /Monday night through Saturday/...
a bit unsettled in the medium range. Models indicating the cold
front will become stationary near the coast Tuesday with low
pressure moving northeast along the front keeping the region in
scattered showers and thunderstorms. Precipitable waters above 2 inches could
result in heavy rain from Monday night through Tuesday. Surface
low pressure develops on the from Wednesday and moves northeast
scraping along the coast of Maine. Both GFS and European model (ecmwf) are similar
but the GFS is more robust with the surface low. At any rate showers
and thunderstorms may linger along the coast through early
Thursday while more interior locations see some clearing
Wednesday.

&&

Aviation /14z Sunday through Thursday/...
short term /today through Monday/...VFR lowering to MVFR/IFR in
developing scattered to maybe occasional rain showers/thunderstorms later today and
tonight and continuing on Monday. Some h/f that could lower visibility and
perhaps ceiling early this morning then again later tonight into Monday.

Long term...expect MVFR/IFR Monday night and Tuesday. Interior
locations will become VFR Wednesday while coastal location remain
MVFR/IFR. VFR returning Thursday.

&&

Marine...
short term /today through Monday/...updated to input latest
observed data resulting in minor, if any, adjustments to the
previous forecast. Will continue the Small Craft Advisory for this afternoon through tonight as
S SW winds should increase along with building seas...first over
the open waters then extending even into the bays. Winds let up
for Monday...with seas a little slower to respond.

Long term...Small Craft Advisory may be needed Monday night through Wednesday.

&&

Tides/coastal flooding...
an astronomical high tide of 11.7 feet at Portland, which will be
one of the highest of the year, will occur at 1236 am Monday. The
11.6 feet predicted tide at 1143 PM Saturday reached 11.84 feet. An
increasing southerly flow and building seas should push the surge
higher than the 0.24 feet of this past high tide. This will likely
cause the tide to reach...or go slightly above, the 12.0 tidal
flood stage at Portland. Some minor coastal flooding and
splashover is possible...therefore have issued a coastal Flood
Watch for the high tide tonight...from 11 PM to 2 am.

&&

Gyx watches/warnings/advisories...
ME...coastal Flood Watch from this evening through late tonight for
mez023>028.
New Hampshire...coastal Flood Watch from this evening through late tonight for
nhz014.
Marine...Small Craft Advisory from 2 PM this afternoon to 8 am EDT
Monday for anz150>154.

&&

$$

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