766
FXUS61 KBGM 110159
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
959 PM EDT Wed Jul 10 2024

.SYNOPSIS...
Showers and lingering thunderstorms gradually exit the area
toward after midnight, with quieter weather moving in
overnight. A few showers will linger over portions of Central NY
into Thursday, before high pressure builds back in for the end
of the week and weekend.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...

1000 PM Update...

Showers and thunderstorms continue to slowly move east-northeast
through the eastern half of the forecast area this evening. The
main threat is shifting more toward heavy rain and hydro/flash-
flooding issues as torrential downpours occur. A few storms
could still produce gusty winds and even have some rotation. The
tornado watch is set to expire within the next hour.

Thursday will be much cooler, partly to mostly cloudy with a
breezy west-southwest winds 8-15 mph hour. Highs are only
forecast to reach into the 70s for most of the area.

745 PM Update...

Busy afternoon and early evening with numerous rotating super
cells moving through the area. The severe and isolated tornado
threat continues mainly east of I-81 in Central NY and all of NE
PA...this is where a Tornado Watch remains in effect. Sig Tor
parameter remains 1-2 for the areas noted above, with 0-1 SRH
150-200m2/s2, 0-1 km shear increasing to 20-25kt...overall
supercell composite is an impressive 8-12 over the region owing
to MLCAPE 1000-2000 J/kg and bulk effective shear 40-50kts. A
line of thunderstorms will continue rolling east into the
Catskills, Wyoming Valley and Poconos between now and 11pm or
midnight....again the severe/tornado threat continues here.

Flash flooding also remains possible along and east of I-81 as
the slow moving line moves east with torrential downpours from
the t`storms embedded....pwats are off the charts 2.2 to 2.3
inches with impressive southerly 850mb moisture transport.
Rainfall rates of 1-3 inches per hour are possible through
midnight.

150 PM update...
Main concerns in the near term remain focused on the threat for
severe thunderstorms producing damaging winds and tornadoes this
afternoon and into the evening hours. We are also concerned for
the threat of heavy rain leading to localized flash flooding.
Heat and humidity also continue today across most of central NY
and northeast PA.

A very unstable air mass has developed across much of the
interior Northeast this afternoon ahead of an approaching low
pressure system that contains the remnants of Beryl. There is a
rich air mass associated with the system, which has combined
with a supplemental plume of deep moisture that is advecting
north into the region. We have already seen a couple of discrete
rotating thunderstorms move north within the warm sector and we
are currently watching a line of discrete storms in western NY
start to move into Steuben county and these storms will be the
focus of attention into the evening.

Very favorable deep and low level shear will create very
favorable conditions for rotating storms and the threat for
tornadoes. Deep convection will also lead to the threat of
strong damaging straight line winds as the storms grow upscale
into the evening.

The threat of heavy rain will be highest along and north of the
I-90 corridor where multiple rounds of heavy rain are possible
which could lead to several inches of rain in a short period of
time.

After the sun sets tonight, there will be a loss of instability
and the stronger dynamics will also shift off to the east. The
parent low pressure system will move out tonight and a slightly
cooler and much drier air mass will advect in behind the system
into Thursday. Highs on Thu will only climb into the upper 70s
and 80s with dew points in the 60s. A very comfortable day.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
1130 AM update...

A weak slow-moving surface boundary will be hung up along the
East Coast Fri and Sat and allow for a persistent threat of
showers and storms. The most favorable chance for precip will be
over the Catskills and Poconos. A ridge of high pressure will
set up farther to the west and keep areas west of I-81 mostly
dry and quiet. Temperatures will remain hot with highs in the
80s and lower 90s. Humidity will remain elevated but not
extreme...with dew points in the 60s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
1130 AM update...

The weak ridge over the interior NE Saturday night will slowly
trend to the east through the rest of the weekend. This will
bring a brief period of dry/quiet weather to the region Sat
night and Sun. There could be a few popup thunderstorms Sunday
afternoon/evening, but better chances for convection exist
Monday and Tuesday as the ridge breaks down and the synoptic
pattern becomes more cyclonic. Precipitation chances will be
elevated during the late afternoon/evening hours during peak
heating.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
800 PM Update

Thunderstorms will continue to be possible at most taf sites
through 02-03z this evening...this was covered by tempo groups
in the tafs. As the t`storms move thorough visibilities may
drop to IFR or lower at times. The storms should be east of our
taf sites by 03z this evening.

After this, cloud bases and CIGs fall to MVFR/MVFR Fuel Alt
overnight into Thursday morning at all of our taf sites. CIGs
likely continue at MVFR Fuel Alternate at all taf sites (except
AVP) most of the day on Thursday. AVP will be mainly MVFR all
day Thursday. There is also some chance for occasional IFR CIGS
at SYR and RME from 19-23z...but it will be borderline.

South-southwest winds tonight turn westerly Thursday afternoon
between 5-15 kts.


Outlook...
Thursday night...Gradually becoming VFR from west to east.

Friday through Monday...Mostly VFR conditions with isolated
showers possible.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...Flood Watch until midnight EDT tonight for NYZ009-018-036-037.

&&

$$

SYNOPSIS...BJT/MJM
NEAR TERM...BJT/MJM
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...KL/MPK