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000 
FXUS61 KGYX 142036
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
336 PM EST Thu Nov 14 2019

.SYNOPSIS...
Some very light snow will cross parts of the area early this 
evening before we dry out. We will be a little warmer Friday but
this will be occurring ahead of a strong cold front. The front
crosses the area with snow showers and squalls along with
sharply falling temperatures. Expect to fall back into the teens
and single digits again Friday night. Below normal temperatures
stick around through the weekend with a warming trend and a
return to active weather next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Early this evening we should continue to see very light snow
across much of the Nrn half of the forecast area. This is due
mainly to a couple of moist layers within the WAA regime. Weak
lift in the layer around 10000 ft is likely producing some ice
crystals which are falling into the shallow low level clouds.
This is leading to light snow but unlikely to see much
accumulation...if any outside of the mtns. 

With increasing clouds and light Sly flow the temps overnight
will be much warmer than last night...which is not saying much. 

Will have to watch the amplification of a weak wave offshore
late tonight...as some guidance is indicating that it will try
and work some moisture back towards the Midcoast. I have light
snow accumulations there confined mainly to the immediate coast. 

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
The main story Fri will be the strong cold front set to cross
the area late in the day. All signs point towards a sharp
boundary approaching the area from the NW around 7 pm. There are
plenty of ingredients in place for snow squalls...including
temps near freezing crash below behind the front. Given the set
up a couple snow squall warnings are not out of the question. 

For starters I blended in some higher-res guidance to capture
the progression of the boundary in the PoP fields. I suspect we
will be able to further refine that motion tonight and with the
early forecast updates Fri. I also used a non-diurnal temp trend
late in the day. S of the front will remain in the 30s...with
temps quickly falling thru the 20s behind it. I also blended in
some raw 2 m temp guidance Fri night...as the CAA should keep
the boundary layer fairly well mixed and stave off any
radiational cooling effects.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Overview: Surface high pressure builds into New England on Saturday 
and settles overhead Saturday night, favoring another cold 
night for the middle of November. Sunday sees the high pressure 
lift northeast as a broad trough moves into the Great Lakes 
region. That trough remains there through Tuesday night, driving
a series of coastal lows up the Atlantic coast that look to 
generally be low-impact for our region. After a chilly start, 
temperatures will gradually warm each day through the period. 

Impacts: No significant impacts anticipated on land at this time, 
but the coastal systems next week will be monitored as any 
westward changes in track could lead to impacts. 

Details: Saturday morning will begin with our region in the wake of 
an arctic front and surface high pressure building into New 
England. Expect a clear and sunny day, even in the mountains 
with no precipitation. The high should be nearly overhead 
Saturday night, and with clear skies Saturday evening, 
temperatures will likely drop quickly after sunset and 
conditions will be near ideal for radiational cooling. The only 
complicating factor is clouds expected to move in after 
midnight, especially in southern portions of the region, may cut
off the cooling thereafter. All that said, blended guidance 
that weighted some cooler solutions a little more heavily and 
came up with near zero in the mountains to the lower to mid 
teens along the coast and in southeast NH. This will easily be 
the coldest night of the long term period.

Sunday sees the surface high move northeast as an upper level low 
moves up the Atlantic coast and a broad upper level trough 
enters the upper Midwest/western Great Lakes. The trough will be
the primary influence on our weather through the rest of the 
period as the upper lows looks to pass to the east of the 
benchmark Monday night. Over land, clouds will build along the 
ME coast and in southern NH on early Sunday, gradually spreading
northward into the mountains late Sunday evening. We should 
remain dry during the day, but precipitation chances are 
introduced Sunday night as the low approaches. 

The rest of the forecast is rather low confidence as the pattern 
becomes a little more active and unsettled. Monday looks rather
cloudy with a mix of rain and snow showers. The low pulls 
northeast on Tuesday, but the upper trough over the Midwest digs
south toward the southeast U.S. and slowly moves east through 
Wednesday night. The trough picks up on a southern stream 
disturbance and it then races up the Atlantic coast late Tuesday
through Wednesday. Stuck pretty close to the long-term model 
consensus PoPs Monday through the end of the period, which 
results in chance PoPs for most of the region each day. Also 
stuck with snow/rain showers or a mix of the two for weather as 
there sill be ample time to fine-tune p-types as this part of 
the forecast comes into better focus.

Saturday looks to be the coldest day of the period as we
experience a gradual warming trend that ends with temperatures
close to normal in the early-mid part of next week.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
Short Term...Local IFR in the mtns early this evening as -SN
crosses the area. Will have to watch for a period of IFR in -SN
at RKD this evening in a window from 23z to around 5z. Otherwise
conditions are expected to be VFR or trending to VFR overnight.
A strong cold front and sharp wind shift will cross the area
from NW to SE early evening Fri. Local IFR or lower conditions
are possible in SHSN along the front as well as surface gusts to
25 kt in the vicinity of any SHSN.

Long Term...With high pressure building in, generally calm winds
and VFR conditions expected at all terminals through Sunday.
MVFR conditions expected at the southern NH and southwest ME
terminals beginning Sunday night as clouds move in from the
south; these conditions gradually spread to all terminals by
Monday morning. Unsettled Monday through Tuesday night as clouds
dominate and -SHSN/-SHRA bring occasional IFR conditions to all
terminals.

&&

.MARINE...
Short Term...SCA conditions will develop tonight outside the
bays and in the bays Fri on SW flow. A gale watch has been
issued for strong NW wind gusts behind a strong cold front Fri
night. 

Long Term...Gales likely to be in effect for the outer waters
Saturday morning, but winds diminish below 25 kt by Saturday
evening. Winds and seas build again late Sunday through Monday
with seas to 10-11 ft possible on Monday. Conditions begin to
improve on Tuesday and remain below SCA criteria through the
rest of the period.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory from 6 AM to 6 PM EST Friday for ANZ153.
     Gale Watch from Friday evening through Saturday morning for 
     ANZ150-152-154.
     Small Craft Advisory until 6 PM EST Friday for ANZ150-152-154.
     Small Craft Advisory from 1 AM to 6 PM EST Friday for ANZ151.

&&

$$

NEAR TERM...Legro

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