843 
FXUS61 KBGM 241934
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
234 PM EST Wed Nov 24 2021

.SYNOPSIS...
High pressure will weaken as a frontal system moves into the 
central Great Lakes tonight. Clouds will increase from the 
west, keeping temperatures in the 20s and 30s overnight, warmest
over the Finger Lakes region. For Thanksgiving Day, 
temperatures will warm back up into the 40s, and a few 
sprinkles will possible as clouds increase. Scattered rain and 
snow showers will spread across the area Thursday night into 
Friday, with lake effect snow showers persisting into early 
Saturday. A clipper system will bring additional snow chances to
the area on Sunday and Monday, as coastal low develops off the 
New England coast.

&&

.NEAR TERM /THROUGH THURSDAY/...
225 PM Update...
High clouds are beginning to spread into western NY/PA ahead of
the next system, and will continue to do so overnight, gradually
thickening and lowering. This, along with light southerly flow
aloft, will help keep temperatures quite a bit milder tonight,
with 30s west, and mid to upper-20s east.

A weak shortwave trough will ripple through the area tomorrow
(Thanksgiving) morning. It will encounter a very dry low level
airmass, and though several CAMS show light simulated
reflectivity echoes, they also show minimal to no accumulation.
BUFKIT soundings suggest most areas will see clouds and virga,
with perhaps a sprinkle over central NY through early afternoon.
Shower chances will increase late in the afternoon west of I-81
in both NY and PA. Precip type will favor rain and early on maybe
an ice pellet or two with evaporative cooling. Cold front pushes
through the Finger Lakes after Midnight, reaching the Hudson
Valley by dawn. Precip type will shift to all snow behind the
front, but dry slotting aloft and unfavorable jet streak
positioning for larger scale lift will limit precip amounts and
coverage behind the front. Some parts of northern and western 
Oneida County may just start seeing some wrap-around lake 
effect snow work in off Lake Ontario before dawn Friday.

1250 PM Update... No major changes to the forecast grids 
through today.


636 AM Update...
Only minor changes with sunrise update, forecast on track 
discussed below. 

A sunny but somewhat chilly day under high pressure. Although we
have a cold start this morning plenty of sunshine and weak
southerly/southwesterly flow should get most locations into the
lower 40's for highs today. High clouds slowly increase tonight
and Thursday ahead of an approaching cold front. Despite models
indicating some showers by Thursday afternoon an initial dry 
layer near the surface should keep most locations dry 
throughout the day. A few light rain showers can not be ruled 
out west of I-81 by sunset. Temperatures don't fall much 
Wednesday night with the weak southerly/southwesterly winds then
push 50 Thursday in many spots.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
315 AM Update...

Rain showers are likely for most of the region Thursday night as
a strong cold front approaches the region. A rain/snow mix will
be possible as well as snow showers in higher elevations, 
though little to no accumulation is expected during the 
overnight hours. Overnight lows will be around freezing.

A low over Quebec will drag the front through Friday morning, 
allowing for temperatures to continue to cool and more snow mix 
in. The highs will be reached in the morning with temperatures 
in the mid 30s to low 40s. There may be a brief break from any 
precipitation around mid-morning once the front passes through. 
The main snow threat will come Friday afternoon as the low
continues to move eastward with wrap-around moisture moving 
into our region. Northwest flow will also support some lake 
effect snow showers. These two features will bring accumulating
snow Friday night and into early Saturday morning for mainly 
CNY. Wind gusts up to 30 mph, possibly higher, will be possible
when some of the heavier snow is expected. This could lead to 
white-out conditions as well as slippery roads. Extra caution 
will be needed for any travel Friday night.

Snow ratios and accumulations were not changed much, though 
there was a slight reduction in this forecast update due to
a small decrease in QPF. Still, snow ratios ramp up to 15:1 
Friday night and a few inches remains possible for portions of 
the Finger Lakes Region and western Mohawk Valley. Overnight 
lows will be chilly as much cooler air moves in after the 
frontal passage. Temperatures will be in the 20s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
315 AM Update

Lake effect snow showers will hang around through Saturday while
tapering off during the afternoon. A area of high pressure moves
into the region Saturday night. There does remain a slight
chance for some lake effect snow showers Saturday night. Snow
showers return Sunday afternoon as a low pressure system moves
just south of our region. There are some timing differences 
between models but there is general agreement that the Twin 
Tiers and areas southward have the best chance for some snow 
showers or rain/snow mix. National Blend of Models (NBM) was a 
little off on the PoPs for this system, so a solution closer to
the GFS (00z) and ECWMF (12z) was used. This results in snow 
showers clearing out by Monday morning. Northwest flow could 
support additional lake effect snow showers early next week 
which could then be followed by another system to our north.

Highs during this period will be in the mid 30s and low 40s. 
Overnight temps will range from the upper teens to upper 20s. A 
slight warming trend is possible heading into early next week.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR conditions with light southerly winds will prevail with 
some high clouds increasing in the afternoon and evening hours.
As a system approaches from the west, a weak leading shortwave
trough will move across the area Thursday morning, but will
encounter a dry low level airmass. Clouds will increase, with
ceilings down to around 5000 to 8000 feet, and a few sprinkles
will be possible at western sites (ELM and ITH) between 10Z and
15Z, but with no restrictions. 

Outlook...

Thursday afternoon...VFR conditions will prevail, though
ceilings will slowly lower.

Thursday Night through Friday...A system will cause some
restrictions with rain and snow showers. 

Friday night through Saturday... Potential lake effect snow 
showers with restrictions, especially NY terminals otherwise 
VFR. 

Saturday Night...Conditions improve to VFR all areas as lake 
effect snow ends.

Sunday...Another system developing to our southwest and shifting
offshore will bring a risk of rain and snow with associated
restrictions, most likely later Sunday and Sunday night.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.

&&

$$
SYNOPSIS...MWG
NEAR TERM...MPH
SHORT TERM...BTL
LONG TERM...BTL
AVIATION...MPH