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000
FXUS61 KGYX 150416
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1216 AM EDT Sat Jul 15 2017

.SYNOPSIS...
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An upper level trough of low pressure over the Great Lakes will
move east tonight and across northern New England Saturday,
while weak low pressure passes to our south. Scattered showers
and widely scattered thunderstorms will occur along and in
advance of this trough overnight and Saturday. As the trough
exits Saturday night, clearing and drier weather can be
expected that will last into Sunday. Another trough of low
pressure approaches from the west late Sunday and and stalls to
the west of New England Monday and Tuesday with more unsettled
weather.
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&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...

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1214 AM...Minor ESTF update to reflect current mesonet and radar
trends in near term grids.

Prev disc...
940 PM Update...
Another update to adjust PoPs across the region. Showers are
scarce at the moment with some moving through the Mid Coast
region of Maine and more over VT and NY along a stalled front.
Convection continues to weaken as it moves east. Stratus and
fog were developing across the region with plenty of moisture
still in place. Have lowered PoPs to slight to chance PoPs for
the most part as even the CAM models are having a hard time with
precipitation placement and movement. Other parameters were
adjusted to reflect these ideas.


735 PM Update...
Forecast was updated to adjust PoPs and weather grids based on
latest CAM models and radar data. Some isolated thunderstorms
are still occurring across the region with the biggest area of
convection over the Moosehead Lake region. Additional cells
were still forming over NY State as well as VT. Any
precipitation has the potential to be heavy but basic average
QPF amounts will be light. Cloud cover and dew points will keep
temperatures up with readings only dropping a few degrees by
morning.


Previous discussion...
An upper trof over the eastern Great Lakes will slowly move east
tonight. Meanwhile the weak ridging off the coast will continue
the light moist maritime onshore flow. The HRRR model brings
the developing convection over central and upstate NY this
afternoon into NH by 00z and then moves a large area of
convection across the rest of the cwa by later in the evening.
Will go with the likely POPS offered by models for tonight.
Due to the shallow nature of the sfc maritime air mass over the
region, the elevated convection developing to the west should
be able to hold together as it moves across the region tonight.
Will have some enhanced wording for some heavy rain and gusty
winds in some of the storms through 06z tonight. Due to very
little ventilation and plenty of low level moisture, will also
have the mention of some developing fog overnight. Used a blend
of models with more weight on the NAMDNG guidance for overnight
lows which should be in the 50s.
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&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM SUNDAY/...
The upper trof moves over the area Sat and then exits northern New
England to the east Sat night. Scattered showers and possibly an
isolated thunderstorm will accompany the trof Saturday but come to
an end by Sat evening. Preference of better detail from the NAMDNG
model for max/min temps was used.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
An upper level trough will approach from the west on Sunday.
However, short wave ridging overhead should keep most if not all
showers/thunderstorms to our west Sunday.

The trough gets a bit closer on Monday so the chances for
showers and thunderstorms will increase in western and central
zones, but still should be the hit or miss variety. The same
thing can be said for Tuesday but the shower and thunderstorm
activity should be a bit more widespread with better forcing for
ascent moving on in.

Thereafter, we should have a fair weather day on Wednesday before
another short wave trough approaches and brings renewed chances for
showers and thunderstorms for the end of the week.

&&

.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
Short Term /through Saturday/...Variable conditions mostly MVFR to
IFR tonight into late Sat in stratus clouds, sct -shra, and
patchy fog. From 22z-08z wdly sct -TSRA also possible.
Conditions improve to VFR aft 21z Sat.

Long Term....Mainly VFR expected Sunday and Monday expected
although some stratus and fog may develop on the coastal plain
during the two nights as onshore flow develops.

&&

.MARINE...
Short Term /through Saturday/...Winds and seas to remain below
SCA criteria through Sat night.

Long Term...A weak pressure pattern looks to keep sub-sca
conditions around through early next week.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$

ES