467
FXUS61 KBGM 051813
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
213 PM EDT Fri Jul 5 2024

.SYNOPSIS...
Another warm and muggy afternoon expected with isolated to
scattered showers and thunderstorms. A weak front moves through
tonight helping to move some of the moisture out of the region
with Saturday looking drier especially later in the day. Hot and
muggy weather returns next week with frequent chances of
showers and thunderstorms.

&&

.NEAR TERM /THROUGH SATURDAY/...
1015 AM Update...

Increased cloud cover across the area for the rest of the
morning and into the early afternoon hours based on the latest
GOES East Visible imagery and 12z HRRR. Guidance shows drier air
mixing in and clouds finally breaking some by about 2-4 PM; but
it will still be partly cloudy at best. An area of rain is
moving across the Twin Tiers and western Catskills at this time.
CAMs show thus area of light to moderate rain slowly translating
east into the early afternoon, with perhaps a slight uptick in
convective activity surrounding it. MLCAPE is low, just 100-200
J/Kg due to all the cloud cover and lack of surface heating thus
far. This will beginning to increase toward 500-1000 J/Kg by
late afternoon and evening as daytime heating increases low
level lapse rates. The other story for today are the very high
dew points in the low to mid-70s out there. This will certainly
make it feel much hotter than the actual temperature. By late
afternoon the heat index looks to peak around 90 for the valley
locations in CNY, but up to 92-99 in the Wyoming Valley.

Updated PoPs to better match the latest 12z HRRR for this
evening and overnight. It appears there maybe two rounds of rain
and t`storms. Number 1 in the evening hours from about 6-10 PM,
moving across CNY then round two after midnight into the early
hours of Saturday morning.

630 am update...
Overall little change to the forecast. Adjusted chances of
precipitation to match radar for the next couple of hours.
Chances of rain were lowered slightly overnight as the 500 mb
shortwave is a bit weaker but there is still plenty of
instability.

315 AM Update...

Cloudy skies overnight has helped keep temperatures warmer with
most of the region still in the 70s early this morning. A
cluster of showers and thunderstorms have developed in central
PA and will be moving into NEPA and the Southern Tier around mid
to late morning. Temperatures for the late morning through the
afternoon were lowered as there will likely be a cold pool left
behind by the rain in the morning. Dew points were once again a
little high with the NBM so some of the NBM 10th as well as the
Canadian Reg were blended in to drop dew points from the mid 70s
to low 70s.

There is still a lot of uncertainty in the precipitation
chances through the day as the morning rain will stabilize
things but most forecast soundings do have CAPE recovering by
the mid to late afternoon. Precipitation chances were kept
through the afternoon despite CAMs not showing much. Soundings
show a bit of CIN but it would not be too hard to be a degree or
2 warmer or terrain helps get a couple storms going and outflow
from those get other storms going in the afternoon across CNY
and the Southern Tier.

Tonight, a surface trough moves through that helps spark off a
round of more widespread showers and thunderstorms. It is
possible for a few of these thunderstorms to become severe as
bulk shear is up over 40 knots in forecast soundings and lifted
indexes getting below -5 along with elevated CAPE staying
between 700 and 1400 J/kg through the night. Hail and wind would
be the primary threats with the stronger storms.

With the surface trough moving east of the region Saturday as
well as no discernible 500 mb shortwave, there will not be
anything to trigger storms. Dew points also fall a bit in the
afternoon as some drier air advects in aloft and mixes down with
day time heating. Precipitation chances were reduced and
largely kept at a chance or higher in the Catskills down into
the Poconos.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
A cold front will continue to be slow to push east of the area
Saturday night.  Any lingering showers and or thunderstorms would be
on the isolated side east of I-81. Humidity does ease a bit after
the cold frontal passage resulting in slightly cooler nights with
lows in the 60`s this weekend. Most locations should get well into
the 80`s for highs on Sunday with more sunshine as high pressure
builds into the region.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Heat and humidity will start to increase on the backside of the high
already on Monday. A weak cold front looks to follow for Tuesday and
Wednesday only slowly moving through the region. Modeled boundary
layer temperatures show highs reaching 90 in most locations. Even
just a slight increase in the humidity gets some locations in CNY
close to a 95 degree heat index. Air temperatures look to trend
slightly cooler Tuesday afternoon. However, with the increase
in humidity another day with some locations in CNY pushing 95
for a heat index and a few spots in NE PA pushing 100 for a peak
afternoon heat index. Muggy overnight lows not falling much
below 70 as well.

The weak cold front Tuesday and Wednesday looks to provide enough
lift for the development of scattered showers and thunderstorms
likely with peak coverage each afternoon and evening. An early look
with PW values indicates the atmosphere could be quite juicy for
locally heavy downpours. Currently modeled 0-6km bulk shear of
around 30 knots would indicate some potential for gusty winds with a
few storms as well. Still plenty of time to dive into the details
with this front. Temperatures should trend a little cooler
Wednesday.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...

2 PM Update

Scattered to bkn CIGs between 2500 to 8000 ft agl are lingering
over the region early this afternoon. These should lift to
mainly VFR cloud bases and scatter out more heading into the
late afternoon.

There will be a chance for scattered rain showers and isolated
thunderstorms between about 00z to 03Z, especially for the ELM
and ITH area...but it could also clip SYR, BGM or even RME. This
is round number 1. After a brief break, latest CAMs guidance,
including the HRRR show another more substantial round of rain
moving through between about 06-12z overnight into early
Saturday morning. There could also be embedded thunderstorms
during this timeframe as well. The highest instability looks to
be over the BGM and AVP area during the overnight hours, so
included PROB30 groups for TSRA here. Otherwise, with the clouds
and periods of rain not expecting widespread fog, but areas of
patchy fog are certainly possible even across the higher
elevation taf sites.

The rain showers should exit the area after daybreak Saturday
morning, but MVFR CIGs may linger through mid morning. Becoming
VFR by midday Saturday, but there will still be isolated
thunderstorm around, especially north of BGM, including the
ITH-SYR-RME area into the afternoon.

Outlook...

Saturday afternoon & Saturday Night...Isolated thunderstorms,
then areas of fog overnight with associated restrictions.

Sunday and Monday...Mainly VFR.

Tuesday and Wednesday...Showers and thunderstorms possible,
with associated restrictions.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...Air Quality Alert until 11 PM EDT this evening for NYZ062.

&&

$$

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