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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 241137 AAA
AFDGYX

Area Forecast Discussion...UPDATED
National Weather Service Gray ME
637 AM EST Thu Jan 24 2019

.SYNOPSIS...
Low pressure will drag a trailing cold front across the area
today as it passes by to our north and west. Weak low pressure
will approach from the west Friday, before crossing the region
Friday night. A weak ridge of high pressure will pass over the
region Saturday. Low pressure will track through southeastern
Canada Sunday, before a cold front sweeps across the region
Monday. High pressure will follow on Tuesday. Yet another area
of low pressure will pass by to our north and west Tuesday night
into early Wednesday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM Update...
Have adjusted temperatures slightly for this update. Portions
of southern NH are warming quickly, with Jaffrey at 49 degrees
this hour. Just a few miles north, temperatures are in the
upper 30s, so there is a large temperature discrepancy as warm
air moves north. Freezing rain is still occurring in the winter
wx advisory area where temperatures are in the 30s. Although
some sites like Laconia, Fryeburg, and Lewiston are above
freezing by a few degrees, local data plots show many other
readings in the lower 30s. So have not cancelled any advisories
and will likely let them go until they expire at 8 AM.
Temperatures will need a lot of adjusting today as this event
unfolds.



Previous discussion...
Synoptic scale flow is currently dominated by a highly
meridional ridge over the west coast, with a deep trough
covering most of the central CONUS. The East Coast also has a
ridge along the length of it. The coldest center of the trough
was located well to the north near Hudson Bay, where
temperatures are in the -30 to -40F range. A piece of the polar
low will dip down into the northern Plains today and push a
downstream short wave across our forecast area. At the surface,
a warm front was located in southern Canada with a surface low
progged to deepen as it moves east from the Great Lakes.

Precipitation associated with broad warm advection was spreading
across northern New England this morning with a mix of
precipitation types as the warmer air advanced northward. In
general, the winter wx advisories across southern NH and
southern Maine were allowed to expire with p-type having changed
to light rain. Elsewhere to the north advisories remain in
place mainly for freezing rain which will last longest over
northern Coos, N. Oxford, N. Franklin, and central Somerset
Counties.

Even as the winter weather threat begins to come to an end
there are still a couple more hazards we have to deal with,
including moderate to heavy rain and strong winds. Concerning
the rain, CAMs are showing several slugs of rainfall moving
through today, some of which will be concentrated on a trailing
cold front moving through later this afternoon. PW values are
around 225% to 250% of normal, and this combined with poor
drainage due to snow and ice has prompted a flood watch for
southern NH and SW Maine (basically where their is not as much
snowpack to absorb the rain). Ensemble river forecasts are also
pointing towards several rivers reaching minor flood stage.

In tandem with low pressure moving across the forecast area
today, a strong LLJ approaches from the south and pivots over
the region, peaking around 100 kts offshore. A wind advisory
remains in place for the coast for today and tonight with gusts
to 40-50 mph possible. Temperatures warm into the 40s to near 50
today, which will help mix winds aloft down to the surface. In
addition, the strong winds are not very far off the ground, less
than a 1k ft in some cases, and the heavier rain expected will
also help bring the winds down to the surface.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Clouds and showers linger for the mountains overnight with lows
in the teens north to 20s south. Cooler tomorrow with highs in
the mid 20s to mid 30s with clearing skies downwind. A trough
crosses the forecast area bringing light snow showers to the
mountains and the CT River Valley.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Ensemble and deterministic model solutions remain in good agreement
on the long wave pattern through the upcoming weekend and well into
next week. The current high amplitude pattern across the CONUS will
remain locked in place featuring the west coast ridge and a deep
trough across the remainder of the lower 48. The real question
this forecast period is when and to what degree phasing occurs
between northern and southern stream energy. Otherwise...we`re
left with a dominant northern stream and below normal temperatures
with repeated outbreaks of arctic air across the region punctuated
by brief warm ups ahead of several disturbances. At present...models
are suggesting the potential for a significant winter system
Tuesday into Wednesday next week. However some uncertainty remains
as energy responsible for this system is still well out over the
data sparse Pacific Ocean at moment.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Short Term...Conditions are ranging from IFR to MVFR this
morning in FZRA and RA. HIE should be the last to change over to
plain rain and this should occur later this morning. Winds will
increase out of the south tomorrow with gusty winds along the
coast reaching 30kts. Aloft a very strong LLJ will result in
LLWS at all sites through the day. Rain comes to an end towards
00Z today.

Long Term...

Sat...Sct MVFR in mtn -shra.

Sun...Areas of MVFR in -sn.

&&

.MARINE...
Short Term...Increasing southerly flow will reach storm force
on the eastern waters as a very strong low level jet moves
through the region. In the bays and further west have left
gales as the core of the jet will pass to the east...however a
few gusts to storm force are possible.

Long Term...

Sat - Mon...SCA`s psb outside the bays.

&&

.TIDES/COASTAL FLOODING...
High astronomical tides will continue today. High water levels
will combine with building seas to produce beach erosion and
splash-over near the time of the early afternoon high tide. A
coastal flood statement has been issued for early this
afternoon.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory until 8 AM EST this morning for
     MEZ012>014.
     Flood Watch through this evening for MEZ018-019-023-024.
     Wind Advisory until 9 PM EST this evening for MEZ023>028.
     Winter Weather Advisory until 11 AM EST this morning for
     MEZ007>009.
NH...Winter Weather Advisory until 8 AM EST this morning for
     NHZ001>006.
     Flood Watch through this evening for NHZ007>015.
     Wind Advisory until 9 PM EST this evening for NHZ014.
MARINE...Gale Warning until 9 PM EST this evening for ANZ151-153-154.
     Storm Warning until 9 PM EST this evening for ANZ150-152.

&&

$$

NEAR TERM...Hanes
SHORT TERM...Hanes
LONG TERM...Schwibs