575
FXUS61 KBGM 131807
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
207 PM EDT Sat Jul 13 2024

.SYNOPSIS...
High pressure will dominate our weather tonight and most of
Sunday with warm and increasingly humid conditions. A warm front
will bring a few showers and thunderstorms to the region late
Sunday night into Monday with continued very warm and humid
conditions. The heat and humidity will combine for heat indices
from the 90s to around 100 degrees Monday and Tuesday.
The heat will break by mid week as a strong cold front moves
through the region with showers and thunderstorms and a return
to cooler and less humid air for the end of next week.
&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
Visible satellite shows scattered to broken cumulus under high
pressure. There were a few isolated showers popping up with the
afternoon heating in the higher terrain of the Catskills. With
continued insolation we will see a few more isolated showers
this afternoon in these areas. After the sun sets all this
limited shower activity will die down with clear skies and light
winds for tonight. We expect plenty of valley fog to form in
the twin-tier region into the Catskills where the terrain is
rugged enough for stronger mountain valley circulations. This
will lead to chillier air in the valleys and fog formation.

Then during the day Sunday heating will burn fog off, and lead
to scattered cumulus. The next upper level short wave will
ripple through the Great Lakes Sunday afternoon and lead to a
few showers and even isolated thunderstorms Sunday night. The
atmopshere will be stable most of the night so shower activity
will be slow to reach the entire forecast area. Have POPs
increasing through the night to cover this.

Heat indices on Sunday will be mainly high 80s to mid 90s so no
heat advisories needed for Sunday.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
349 AM update...

Main concerns in the short term are focused on the threat of
strong to possibly severe thunderstorms during the afternoon and
evening hours of Mon and Tue this week. We are also concerned
about the threat of very hot and humid conditions both Monday
and Tuesday as well.

A broad swath of quasi-zonal flow will extend from the Great
Lakes into the Northeast US Sunday night through Tuesday. Within
this flow, several embedded short wave and left over convective
complexes to the west will ripple through the area. Persistent
west/sw flow across the area will allow the warm air mass to
continue and build over the Northeast early in the week. This
pattern will also draw northward a very humid air mass which
will primepeak on Tuesday with
heat indices the atmosphere for more intense afternoon/evening
convection.

The challenge will be determining the timing and location of
the highest threat for scattered showers and thunderstorms. This
will depend highly on the development and track of convection
farther upstream and how it evolves as it moves into NY and PA.
We really cannot rule out rain any time across the forecast area
Monday through the day Tuesday, but the most favorable time for
strong to possibly severe thunderstorms looks to be during the
afternoon/evening hours Monday and again Tuesday. Conditions
look more favorable on Tuesday afternoon with around 1000-2000
J/kg of ML CAPE and 20-30 kt of deep layer shear and weak to
modest forcing from a potential passing mid level short wave.

The impacts from the hot and humid conditions mentioned above
may not just be limited to thunderstorms. Temperatures on Monday
will warm into the upper 80s and lower 90s...and dew points in
the lower 70s will create heat indices of 90-100. Temperatures
on Tue may be a couple deg warmer with slightly higher humidity
as well. Heat indices on Tuesday could top out around 95-105.
Heat Advisories will be needed and Excessive Heat Warnings are
not off the table either.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
349 AM update...

The synoptic pattern starts to gradually turn more cyclonic
over the Northeast/Great Lakes Tue night as an approaching cold
upper low over Ontario slowly drops south into the northern
Great Lakes. A cold front on the lead edge of this pattern
change will swing through the region on Wednesday. The
environment south and east of a line from Corning-Ithaca-Utica
will likely remain unstable enough Wed afternoon for more strong
to possibly severe storms. Surface temperatures climbing into
the upper 80s and 90s, with low 70 dew points and the passage of
the front should prove sufficient for strongly forced ascent
leading to thunderstorms. There is still timing uncertainty with
the frontal passage, but it does appear that it will be clear
of the area some time Wed night.

High pressure builds in on Thu and Fri with much cooler and
drier air in place. High temperatures will only climb into the
70s to near 80, with dew points in the 50s and lower 60s.
Overnight lows in the 50s and 60s will be a welcome relief.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Mostly scattered VFR cumulus have formed across of all central
NY and northeast PA with a few clumps of broken ceilings mainly
over the western Catskills and high elevations of northeast PA.
All terminals were VFR in scattered cumulus. There could be an
isolated shower or even a storm but the chances are less than 20
percent and current radar shows nothing near our terminal
sites. After the sun sets, skies will clear and we will see
light winds. This is a great set up for strong net radiational
cooling. With light synoptic scale winds, mountain valley
circulations will allow chillier air to sink in our valleys of
the Twin Tier region to western Catskills and even down into the
Wyoming Valley. Terminals that will see IFR conditions will be
KELM 8-14z. The rest of the terminals will be VFR overnight. For
Sunday morning we expect fog to burn off at KELM with VFR
conditions all terminals as scattered cumulus again forms toward
end of terminal period.

Outlook...

Monday through Wednesday...Scattered showers and thunderstorms
may bring occasional restrictions; otherwise mainly VFR.

Thursday...Mainly VFR.

&&

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

&&

$$

SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...BJT
LONG TERM...BJT
AVIATION...DJN