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038
FXUS61 KBGM 191901
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
301 PM EDT Sun May 19 2024

.SYNOPSIS...
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Increasing sunshine is expected this evening with temperatures
rising into the 70s. Monday is looking even warmer, with dry
and mostly sunny weather expected. Very warm temperatures are
expected Tuesday into Wednesday. There will be a chance for
scattered thunderstorms later Wednesday into Thursday as a cold
front approaches the region.
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&&

.NEAR TERM /THROUGH MONDAY NIGHT/...

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3 PM Update

Tonight, high pressure remains in place and with radiational
cooling and with plenty of low level moisture (low dew point
depressions), valley fog will likely develop over the region.
There is some question as to how extensive the fog will be, and
if if can reach some of the mid elevation locations as well. It
will be seasonable overnight, with lows in the 50s.

Monday is looking even warmer as 500 mb heights continue to
rise towards 580 dm and 1000-500mb thicknesses reach 567dm.
With ridging in place, a stout subsidence inversion around 700
mb will likely keep most of the region capped despite some
surface based CAPE able to develop with the heat and humidity.
Once again there is a small chance that terrain and or some lake
breezes will help a couple showers or thunderstorms break
through the cap, over the Central Southern Tier and SW Finger
Lakes but odds are low (20%). The rest of the region will see
the fog burn off by mid morning, then mostly sunny skies. The
latest trends in the bias corrected guidance is increasing
temperatures even more...with highs in the mid to upper 80s for
the valley locations...with upper 70s to low 80s over the higher
elevations. Winds will be light west-southwesterly under 10
mph.

High pressure and clear skies continue into Monday night, with
perhaps some patchy valley fog again. It will be milder, with
lows only dipping down into the upper 50s to lower 60s.
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&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
248 PM update...
Main concerns in the short term are focused on the hot air mass
with well-above-normal high temperatures, along with
afternoon/evening showers and storms.

Synoptic pattern will be defined by an upper level ridge
extending from the southern Atlantic coast northward into
southern New England. A surface high off the coast will draw in
moisture from the Atlantic as a potent low pressure system in
the central US lifts into the western Great Lakes and several
weak waves traverse the ridge of the Appalachians into NY/PA.
The air mass will become unstable during the afternoon periods
of these two days. Temperatures will climb into the 80s both
days, with some valley or northern Finger Lake plain/western
Mohawk Valley locations getting close to 90 on Wednesday.
Surface dew points will only push into the lower 60s, so rising
air parcels are expected to only become weak to modestly
buoyant. Forcing along these passing waves will interact with
the unstable environment in the afternoon and evening to produce
some scattered showers and thunderstorms.

Mixed layer CAPE values will hover around the 500-1000 J/kg
range on Tuesday and the highest values should be be mostly
confined to western and the lake plain south of Ontario. Greater
instability is expected to be present on Wednesday...jumping up
to 800-1500 J/kg. Deep layer shear will be minimal across the
region as the region will be generally situated under the upper
ridge axis. This will cause storms to be mostly pulse-type and
on the weak end of the intensity spectrum.

This period will definitely need to be watched if the stronger
dynamics to the west end up shifting eastward closer to the more
unstable air. At this time, widespread severe weather is not
expected.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
248 PM update...
The cold front to the west is expected to push to the east
through the region Wed night into Thu this week and will take
advantage of the 1-1.5 inches of PW, forcing along the front and
a corridor of instability to produce an axis of convection that
will move through the Northeast US during the day Thursday.
Thursday will most likely be the most favorable day for strong
to possibly severe thunderstorms as this front moves through.

The air mass behind the front will be of Canadian origin and
quite dry and cool. Surface dew points in the 40s and afternoon
highs in the 70s will be a nice relief from the hotter
conditions earlier in the week. The next chance of rain looks to
be Saturday night into Sunday.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
Generally VFR level scatter clouds around this afternoon and
early evening, before skies clear.

Tonight, clear skies will likely bring fog formation once again;
developing after 03-06z Monday. ELM has the best chance at fog,
being in valley, and it could be dense here. Went ahead and
indicated a time of IFR/LIFR VSBYs here, especially from about
08z to 12z early Monday morning. For the rest of the TAF sites,
during this 8-12z time period have indicated the potential for
MVFR light fog/mist around the region. There remains a good deal
of uncertainty in exactly where the fog will set up overnight
into Monday morning, and just how low the VSBYs will go. Will
the fog be confined to just the valleys, or more widespread like
some of the guidance is indicating...again, not confident either
way at this time. Will need to monitor trends in the observed
conditions and updated model guidance to get a better feel for
this. The nights are getting shorter, but there seems to still
be enough cooling and time for some fog formation.

Any fog should burn off after 12-13z Monday morning, with a
return to VFR conditions expected for the rest of the day.

Winds will be light and variable under 5 kts through the period.


Outlook...

Monday afternoon through Thursday...Mainly VFR. Some showers
possible late Wednesday through Thursday.

&&

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

&&

$$

SYNOPSIS...MJM
NEAR TERM...MJM
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...AJG/MJM