-- Discussion containing changed information from previous version are highlighted. --
536
FXUS61 KBGM 242332
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
732 PM EDT Fri May 24 2024

.SYNOPSIS...
The quiet conditions will continue through Saturday morning. A
frontal boundary will bring a round of showers and storms to the
region Saturday afternoon and night. This system sweeps through
quickly as Sunday will be mostly dry before the next system moves in
late Sunday night and into Monday.

&&

.NEAR TERM /THROUGH SATURDAY/...
230 PM Update...

High pressure will remain in control through the overnight hours as
well as into Saturday morning. Clear skies and calm winds should
allow for efficient radiational cooling. Patchy valley fog may
during the early morning hours Saturday. Lows are expected to be in
the 40s and 50s, which is below most model guidance.

The first half of Saturday will be dry but a frontal system will be
approaching the region. There is some uncertainty on when convection
may begin, but the latest CAMs show activity during the early
afternoon for far western portions of the Southern Tier and
Finger Lakes regions. SPC has a marginal risk for severe weather
for most counties west of I-81. Model guidance has 1000 to 2000
J/kg with 25 to 35 kts of shear. This will be enough to support
some isolated strong to severe storms. Strong winds and large
hail are the main threats as conditions do not look favorable
for any spin ups. Along I-81 and further east, conditions will
not be as unstable so the threat for strong thunderstorms is low
in these areas. With westerly flow present and skies starting
off mostly sunny, temperatures will climb into the upper 70s to
low 80s.

While there is uncertainty on the timing, all guidance agree that
this system will exit the region overnight, leading to cool and
quiet conditions late Saturday night/early Sunday morning. With the
added moisture from the showers and storms as well as skies clearing
out some, patchy fog/low stratus may develop. Overnight lows will be
in the mid 50s to low 60s, but could be cooler where skies clear the
most.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
230 PM update...

The short term starts off quiet with mid and upper level ridging in
place keeping the region mostly dry and warm. A deepening area of
low pressure in the central US will be lifting a warm front into our
area later in the day with increasing clouds aloft. Precipitation
looks to hold off until Sunday night. Chances of showers and
thunderstorms increase through Sunday night as strong warm air
advection. Forecast soundings show some weak elevated instability
developing but with the lack of steep mid level lapse rates, storms
will stay on the weaker side and not too widespread.

Monday has a better chance for widespread showers and thunderstorms.
Much of NEPA and upstate NY will be in the warm sector of a low
moving through the Great Lakes into Canada with a cold front moving
through in the afternoon. 0-6 km shear is looking to be between 30
to 40 knots but CAPE is on the lower end with a grand ensemble mean
of just under 1000 J/kg with most ensemble members 500 J/kg and
lower. Forecast soundings are pretty saturated so clouds will limit
day time heating and with the lack of any steep lapse rates, CAPE
will be long and skinny. Severe threat looks pretty low as of now
with the marginal parameters but heavy rain and flash flooding may
be more of a concern. PWATs get over 1.5 inches but with some
directional shear in the low levels helps limit backbuilding of
storms but rainfall rates will be high with any storm. With little
capping in the warm sector and the cold front moves through late in
the day, several rounds of storms are looking possible so any
location that gets hit multiple rounds of storms have the best
chance at seeing any flash flood problems. Chances of rain dwindle
behind the front Monday night with drier and cooler air advecting
in.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
230 PM update...

The long term is looking cooler as a long wave trough slowly moves
in. Shortwaves embedded in the flow will still lead to unsettled
weather. Chances were added each afternoon even on quieter days as
the cold air aloft coupled with the strong solar heating plus
greenup will help destabilize the atmosphere in the afternoons. QPF
amounts are not very high in each shortwave this next week as there
is not too much moisture to work with being under the upper level
trough and most of the moisture shunted to the south but ensemble
means on days 3 to 7 do get over an inch for most of the area.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Mostly VFR conditions are expected overnight, with some valley
fog expected to develop. Confidence remains low for fog at ELM,
as dewpoints mixed down to the mid-40s during peak heating. But
with clear and calm conditions, temperatures could well bottom
out close to this point, thus kept the TEMPO groups with lower
visbys in the TAF.

Conditions will improve by mid-morning, with VFR and light south
winds prevailing. A line of showers and thunderstorms will push
west to east through Central NY between 19Z and 23Z, with the
highest confidence in TS at ITH, ELM, and BGM. Thunderstorms
will tend to outrun instability in the evening, and will be
weakening as they approach AVP, but would not likely reach there
until right around 00Z Sun, and are not mentioned in the current
TAF.

Outlook...

Saturday Night... Restrictions possible in fog, especially in
river valleys.

Sunday...Mainly VFR expected.

Monday through Wednesday... Restrictions possible with
scattered showers and thunderstorms.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...BTL
NEAR TERM...BTL
SHORT TERM...AJG
LONG TERM...AJG
AVIATION...BTL/MPH