661
FXUS61 KBGM 050120
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
920 PM EDT Thu Jul 4 2024

.SYNOPSIS...
Very warm and humid conditions last into Friday with continued
risk for more thunderstorms. Saturday is now looking mainly dry,
but still very warm. Sunday and Monday will be dry and mostly
sunny, with continued hot temperatures. A front approaches
bringing showers and thunderstorms to the region next Tuesday.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
915 PM Update...

Forecast grids in decent shape with just minor adjustments to
timing of next rounds of scattered showers and thunderstorms.
CAMS guidance in rather poor agreement leading to low confidence
in forecast, but they do show plenty of potential for
showers/t-storms overnight and then again at times on Friday
across both CNY and NEPA. Will attempt some timing for the
overnight, but generally expecting scattered coverage. A few
adjustments were also made to Friday`s forecast which should
feature a lull in any lingering overnight convection before
atmosphere recovers in the afternoon as noted below.

340 PM Update

A weak boundary resides over the Twin Tiers at this time, aiding
in some minor surface convergence. Surface dew points and low
level moisture are higher across NE PA, mainly in the lower
70s...with mid-60s to upper 60s further north across the rest of
Central NY. Therefore, instability is higher over NE PA with
MLCAPE rising between 500-1000 J/Kg currently. Along this
boundary some scattered showers and t`storms have developed;
these are not moving much and should tend to remain in this
general area while drifting southeast into the evening hours. It
will be very warm and humid into the evening hours, with
temperatures in the upper 70s to lower 80 around sunset.

Difference in the CAMs for late evening and tonight made for a
lower than usual confidence forecast. The HRRR would suggest
much more numerous shower and t`storm activity
overnight...meanwhile the 3km NAM is mainly dry overnight. With
the differences and uncertainty decided to stick with slight
chance PoPs for the overnight period. Will have to monitor
upstream convective activity to see how well it progresses
east-northeast late this evening/overnight.

Friday will be another very warm and humid day, with dew points
pushing into the upper 60s to mid-70s...with the highest surface
moisture across NE PA. High temperatures reach the mid-80s to
around 90...this will produce peak heat indices well into the
90s across our valley locations. It will be very close to heat
advisory criteria in some of the favored urban valley location.,
but confidence wasn`t quite high enough as it will depend on
rain chances/timing and cloud cover.

By afternoon, instability increases between 1000-2000 J/Kg and
deep layer shear increases between 30-40 kts. SPC has the
western half of our forecast area under a Marginal risk for
severe storms, with the main threat being isolated damaging
winds. WPC is also indicating a Marginal Risk for excessive
rainfall over the entire region, as PWATS remain elevated above
1.6 inches, and warm cloud layer depth is up to 13k ft agl. CAMs
suggest a possible remnant MCS/MCV moving into the area which
will initial more convection...exactly when and where this may
track remains somewhat uncertain though at this time.

A front moves in from the west Friday evening and into the
overnight period. This will bring a period of rain and
thunderstorms to the region once again. Additional locally
heavy rainfall is possible with this convective activity.
Localized rainfall totals of 1-2"+ are possible during this
time. With the cloud, showers and a warm south wind...it will be
very muggy with lows only in the upper 60s to mid-70s out there.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A surface low tracks north of our region on Saturday with a cold
front dragging through NY & PA. Front is expected to move through
early Saturday morning with model guidance hinting at lower precip
chances for most of Saturday. A few isolated showers are still
possible with lingering moisture behind the front. Otherwise
temperatures are expected to be quite warm with southerly flow still
in place. Highs will climb into the low to high 80s by afternoon
with lows gradually falling into the low to mid 60s overnight. High
pressure builds over the midwest expanding into our region on Sunday
resulting in dry conditions. Mostly sunny skies will dominate with
highs in the upper 70s to mid 80s. Clear skies will continue into
the overnight hours with calm winds allowing for a possible
radiational cooling setup. Lows are forecasted to range in the upper
50s to low 60s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
High pressure centers over our region Monday with a pleasant start
to the week. Warm and quiet conditions will persist for one more
day, with heat and humidity starting to increase on the backside of
the high. By Tuesday and Wednesday our region rests on the edge of
an upper level ridge with southwest flow and moisture advection.
With heat and humidity in place, passing shortwaves should provide
enough lift to set off showers and thunderstorms. Model guidance
diverges towards the end of the period due to timing
differences. Went with NBM pops showing a chance of showers as
another disturbance moves through the region. Temperatures
during this period are expected to be warm with increasing
humidity as the week progresses. Highs will range in the low to
upper 80s with lows in the 60s at night.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...

VFR is expected for most of this forecast period, especially
across the northern third. Plenty of boundary layer moisture
exists, especially around the terminals that received rainfall
today (KBGM-KAVP). As a result, believe there will be
visibility restrictions at these locations. Persistent high
level clouds through the night along with a weak wave bringing
more scattered showers prevents ideal dense fog formation, so
will generally stick with MVFR mist restrictions during the
late night hours...but IFR or worse is a non-zero chance.
Confidence is just too low at this moment to include.

An initial period of SCT-BKN MVFR ceilings is likely over the
southern half of the forecast area before mixing and lifting to
VFR. Additional showers and t`storms will develop and move
across the forecast area on Friday. Confidence is low on timing
and location.

Outlook...

Friday night through Saturday Night...More unsettled pattern
with chances of showers and thunderstorms with associated
restrictions.

Sunday and Monday...Mainly VFR.

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

&&

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

&&

$$

SYNOPSIS...MJM
NEAR TERM...JAB/MJM
SHORT TERM...ES
LONG TERM...ES
AVIATION...JAB