-- Discussion containing changed information from previous version are highlighted. --
868
FXUS61 KBGM 211839
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
239 PM EDT Fri Jun 21 2024

.SYNOPSIS...
Hot and humid conditions with scattered thunderstorms are
expected again today, with the focus expanding into
northeastern Pennsylvania. A few stronger storms may produce
damaging winds and torrential rainfall. Heat and humidity is
expected to continue through the weekend with relief coming
Monday.

&&

.NEAR TERM /THROUGH SATURDAY NIGHT/...
949 AM update...
Valley fog has scoured out this morning leaving most of the
area under mostly sunny skies. This should be quickly replaced
by a rapidly developing cumulus field that will eventually build
into scattered showers and thunderstorms around or just after
12 PM. Some minor adjustments were made to the forecast
PoPs/Weather/QPF for today into this evening, mainly to account
for the lower chances of precip across the northern counties
after 3 PM. No significant changes were made to the temperatures
and heat indices today. Still expecting highs into the upper 80s
and lower 90s in central/srn NY and lower to mid 90s in ne PA
valley locations. Heat indices will range from 90-105 across the
region.

410 AM Update:

Broad subtropical ridge will retreat southward just a little today.
Weak disturbances embedded in westerly flow aloft will help kick off
scattered showers and thunderstorms again today, mainly focused
along a quasi-stationary front as it sags south towards the NY/PA
line. As a result, precip chances will spread south from CNY into
NEPA today. Localized torrential rainfall will again be favored
today as PWAT values range from 1.75 to 2 inches across the
area, though slightly drier air will begin to infiltrate north-
central NY later in the afternoon as activity pushes south.

Temperatures will be a few degrees cooler today north of the
aforementioned front, with highs topping out in the mid to upper-80s
across north central NY, including Syracuse and the Thruway
corridor. Hotter temperatures and slightly higher dewpoints will be
prevalent from the Southern Finger Lakes into the Southern Tier and
NEPA, where Heat Index values will again reach Heat Advisory
Criteria (95 in NY, 100 in PA).

We`ll see the usual diurnal downturn in precip coverage tonight,
though the southern edge of some areas of showers and thunderstorms
may graze areas north of the Thruway early Saturday. Otherwise,
another round of showers and thunderstorms is expected across the
region Saturday. Max temperatures on Saturday will be similar to
what we see today (Friday), but Heat Index values may encroach on
the 105 mark in the Wyoming Valley of PA. Still enough uncertainty
and time on our side, so kept the Excessive Heat Watch as-is for the
time being.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...

-- Changed Discussion --
The pattern is finally expected to shift Sunday as the strong upper-
level ridge responsible for the long duration heat and humidity
begins breaking down as a shortwave trough and surface cold front
approach from the west. This will lead to an increasing chance of
showers and thunderstorms Sunday, especially during the afternoon
and evening when precipitation appears likely. With the cold front
trending a little bit faster early this morning, moving into our
area during peak heating hours, along with 1000-1500 J/kg of surface-
based CAPE in place and 30-40 knots of shear, there will be the
potential for some stronger storms to develop. Mid-level lapse rates
are not very impressive at this point, so this looks to be more of a
wind threat with any potential stronger storms along with heavy
downpours with PWAT values in excess of 1.5 inches. The SPC has
outlooked the entire CWA in a marginal risk this day. With
uncertainty with the timing of the front, cloud cover and the
convection, temperatures on Sunday will be tricky to forecast. Highs
have trended down several degrees across CNY in the low and mid 80s
with the faster progression of the front, while the Twin Tiers into
NE PA range from the mid 80s to the low 90s. This still gets some
heat index values to around 95 for the Southern Tier of NY into NE
PA. So the heat advisory was extended through Sunday with the
afternoon forecast package.

As the front pushes east, the upper trough will lag behind over the
area on Monday, keeping the chance for scattered showers and
maybe a thunderstorm around. However, cooler, drier air will be
moving in for most areas as dew points fall back into the upper
50s and low 60s by the afternoon. Highs Monday are expected to
be from the mid 70s to the low 80s. With the Wyoming Valley
being one of the last spots for this more refreshing air to move
into, highs this day can still reach the mid and upper 80s. It
will feel more comfortable Monday night with lows in the upper
50s and low 60s.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...

-- Changed Discussion --
Only subtle changes to the previous long term discussion. GFS
trended more toward the ECMWF suite with a cooler and more
progressive look later next week. High pressure briefly builds in
overhead Tuesday leading to a dry day before another front looks to
bring the chance for showers and storms back into the area Wednesday
into Thursday. With ridging aloft Tuesday, high temperatures are
expected to trend back into the 80s, but it`s not expected to feel
too humid as dew points remain in the upper 50s and low 60s, but
they will be trending up Wednesday ahead of the front. Wednesday is
expected to also expected to have highs in the 80s, and perhaps
nearing 90 degrees in a few places, before cooler air moves in again
for the second half of the week.
-- End Changed Discussion --

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
Scattered showers and thunderstorms continue to develop and
move slowly across the region this afternoon. The most favorable
timing of TS will be between 19Z and 00Z at ITH, ELM, BGM and
AVP. The potential for precipitation at SYR and RME is much
lower given the more stable air dropping in from the north.
Conditions will stabilize after 00Z and areas of low clouds and
fog are expected to develop once again through the overnight
hours. The most favorable locations for fog are ELM and BGM.
Conditions will remain VFR, after the fog lifts and mixes out
around 12-13Z, through the rest of the period. There could be
some MVFR cigs and light rain showers that move in from the
north just before 18Z and impact RME and SYR, but confidence is
on the low side.

Outlook...

Saturday afternoon through Monday...Spotty restrictions
possible in showers and thunderstorms.

Tuesday and Wednesday...VFR conditions likely.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
PA...Heat Advisory until 8 PM EDT Sunday for PAZ038>040-043-044-047-
     048-072.
NY...Heat Advisory until 8 PM EDT Sunday for NYZ022>025-055-056-062.
     Air Quality Alert until 11 PM EDT this evening for NYZ062.
-- End Changed Discussion --

&&

$$

SYNOPSIS...BJT
NEAR TERM...BJT
SHORT TERM...DK/MWG
LONG TERM...DK/MWG
AVIATION...BJT/MPH