267
FXUS61 KBGM 261051
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
651 AM EDT Wed Jun 26 2024

.SYNOPSIS...
Partly sunny and warm through the early afternoon hours today.
Then, numerous showers and scattered strong to severe thunderstorms
will impact the area by late afternoon into this evening. Rain
showers continue overnight, before conditions dry out with
gradual clearing on Thursday. Expect seasonable temperatures
with dry and mostly sunny skies for Friday.

&&

.NEAR TERM /THROUGH THURSDAY/...

645 AM Update

No significant changes to the near term portion of the forecast
with this sunrise update. Latest visible satellite loop shows a
mix of clouds and sun out there early this morning, with
decreasing clouds expected through the morning and early
afternoon hours. Hourly temperatures were adjusted based on the
latest observations and trends. It is a very warm start out
there today for some locations; many areas are starting out in
the upper 60s to mid-70s as of 6 AM...but the cooler valleys
that decoupled are in the lower 60s. The timing and intensity of
the potential severe storms remains the same on the latest 06z
3km NAM and 09z HRRR runs. For what it is worth the HRRR
continues to show isolated very strong winds (50-65 kts) with
some of the storms early this evening...this is usually
overdone, but it is an interesting signal to see in the
guidance.

430 AM Update

A few isolated to scattered showers will be possible through
daybreak over northern portions of central NY. Otherwise, clouds
will scatter out with mostly sunny conditions later this morning
and into at least the early afternoon hours. It will be warm
with highs generally in the 80s to around 90.

The main concerns in the near term will be a Slight Risk for
scattered severe thunderstorms late this afternoon and evening
from the Twin Tiers and Catskills south across all of NE PA.
There is a Marginal Risk for an isolated severe storm further
north across the I-90 corridor and Mohawk Valley. The main
hazards with any severe storms today will be strong to damaging
winds and torrential downpours, so isolated instances of hail
are also possible. CAMS and model guidance continue to struggle
with the amount of low level moisture (i.e. sfc dew points)
later this afternoon and evening, and therefore the amount of
MLCAPE that will be present. Our CWA will have a tight
instability or CAPE gradient setting up; likely somewhere near
the Twin Tiers.

Based on some of the CAMs, such as the 00z and 06z 3km NAM it
appears that a differential moisture boundary sets up across the
Southern Tier this afternoon, with northerly winds advecting in
drier, more stable air into northern portions of Central NY.
The 00z 3km NAM indicates that for locations able to maintain
sfc dew points in the mid 60s to around 70, SBCAPE could reach
2000 J/Kg, with MLCAPE between 1000-200 J/kg. The highest
amounts of instability will be in place over NE PA, with the
instability gradient setting up over the NY Southern Tier
region. 0-6km deep layer shear is forecast to reach 40-50 kts
over the area. LIs may reach -9 over NE PA along with mid level
lapse rates approaching 7.0C/Km. DCAPE over NE PA and the
Southern Tier of NY will range from 600-1000 J/Kg, which is
favorable for strong, isolated damaging winds to mix down to the
surface in or near thunderstorms. The last several runs of the
HRRR are showing the potential for thunderstorm wind gusts of 50
kts + with some the modeled storm cells; again mainly over the
Slight Risk area mentioned above.

The main timeframe to see these potentially severe
thunderstorms will be from around 5-7 PM in the Central Southern
Tier region, reaching I-81 corridor by 7-9 PM and the southern
Catskills between 8-10 PM. With PWATs up to 1.9 inches over NE
PA and 1.75 in CNY, locally heavy to excessive rainfall and
isolated flash- flooding could also occur with any training
thunderstorms. Further north across the I-90 corridor to Mohawk
valley the limiting factor for severe weather and flash
flooding will be the low atmospheric instability; but still a
marginal risk and worth monitoring trends through the day. After
the strong to severe storms pass by to the east by around 11 PM
this evening an area of stratiform rainfall will linger for
several hours. Areal average rainfall amounts are forecast to
range from 0.5 to 1.0 inch; but certainly higher amounts are
likely where the heavier and more persistent thunderstorms
develop.

Winds turn west-northwest later tonight and a good deal of cloud
cover lingers. Can`t rule out some patchy fog, but confidence
was low due to the increasing wind speeds up to around 10 mph
before daybreak Thursday. Seasonable overnight lows in the upper
50s to low 60s expected.

Clouds linger Thursday morning under the upper level trough in
the moist, cooler NW flow. Eventually drier air mixes out the
clouds, giving way to mostly sunny skies Thursday afternoon.
There will be a northwest breeze between 10-20 mph. Temperatures
will be cooler, but with the afternoon sun it still manages to
reach into the 70s areawide; with low 80s in the Wyoming Valley.
Overall, much quieter weather expected on Thursday.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
330 AM Update...

Quiet period is expected as high pressure remains in control with
persisting dry conditions. Clear skies and calm winds continue into
the overnight hours making it a favorable night for radiational
cooling. Lows will fall into the upper 40s to mid 50s across
the region. Recent rainfall will also lead to favorable
conditions for valley fog development, so have added some
patchy fog through the overnight hours. Similar pattern
continues Friday with high pressure centered over our region.
Mostly sunny skies are expected with temperatures climbing into
the upper 70s to low 80s. Clouds will begin to move in Friday
evening as the next system approaches. Lows will return to
normal with temperatures ranging in the upper 50s to mid 60s.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
330 AM Update...

Low pressure system tracks east and into our region on Saturday
along with a warm front producing showers and thunderstorms. Deep SW
return flow advects warm air and moisture into our region with PWAT
values 2-3 standard deviations above normal. Model soundings also
show a deep warm cloud layer up to 13K feet suggesting heavy
downpours and localized flash flooding is possible. Cold front from
this system will push through on Sunday with more showers and
thunderstorms. Model guidance shows an additional wave dipping
into our region on Monday, which could increase pops, but
decided to stick with the NBM this far out. Otherwise upper
level ridge moves into the region on Tuesday with drier
conditions returning. Another system approaches our area by
Wednesday with more possible showers.

Temperatures during this period fluctuate with highs mostly ranging
in the mid 70s to upper 80s and lows in the 60s. Temperatures
will be slightly cooler on Monday behind the cold front with
highs in the low to mid 70s and lows in the 50s.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
645 AM Update

VFR conditions are expected at all of our taf sites except RME,
through about 21z today. The rest of the area will see mid
level (VFR) clouds lift to mainly high clouds through the day.
It won`t be until the evening hours (21z to 02z Thurs) that
rain and thunderstorms are forecast to quickly overspread the
area.

Rain and embedded thunderstorms, with PROB30 and TEMPO groups
added into TAFs for t`storms at ITH, ELM, BGM and AVP mainly between
21z Wednesday and 02z Thursday, with rain lingering a few more
hours later into the overnight. As these showers and storms move
across the area it will drop to MVFR Fuel Alternate and even
occasional IFR restrictions possible due to low CIGS and VIS.
The highest probability for IFR or lower restrictions will be at
AVP and BGM, first in the thunderstorms then again between
about 02-06z early Thursday. Left the mention of thunderstorms
out of the SYR and RME TAFs, as probability of thunder is much
lower (slight chc) up north, with much less instability in the
model guidance.

Outlook...

Thursday...Lingering CIGs restrictions in the morning; becoming
mainly VFR by afternoon.

Friday...Mainly VFR.

Saturday through Sunday...Restrictions from showers and
thunderstorms possible.

&&

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

&&

$$

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