370
FXUS61 KBGM 300600
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
200 AM EDT Tue Apr 30 2024

.SYNOPSIS...
A warm front moves north early this morning, bringing isolated
rain showers and maybe thunderstorms to the area. A cold front
passage this afternoon and evening will bring widespread rain
showers and thunderstorms. Some of these storms may be severe.

&&

.NEAR TERM /THROUGH TODAY/...
1230 am update...

Increased pops and thunder chances for Oneida County for the
next hour or two. More showers are still expected to form
upstream to the west and move through early this morning so left
the showers and isolated thunder there. Minor changes to

630 PM Update...

No major changes for the near-term forecast update. Decreased
chances for scattered thunderstorms across Central NY through
this evening. Otherwise, forecast remains on track.


330 PM Update...

The frontal boundary remains draped across the Southern Tier,
with 80s to the south and mid 60s to low 70s to the north. Some
isolated showers and storms are expected to develop along and
just south of this front boundary where CAPE is climbing above
1000 j/kg. Some patches of 0-6km bulk shear around 20-25kts may
allow for these storms to get a little more organized and
produce some gusty winds, but severe chances are currently very
low. These shower and storm chances are expected to last into
the evening hours.

Tonight, guidance is showing the warm front pushing north, which
should generate some scattered rain showers and isolated
thunderstorms across NY, moving from SW to NE. Given the already
warm and moist boundary layer, any additional rain will help
generate patchy fog, especially in river valleys. Lows tonight
will be very warm thanks to the warm front pushing north with
mid 50s to low 60s expected. Oneida county should remain in the
low 50s as it looks like the warm front will not move through
the area. Where rain falls will create cold pools, with
temperatures falling into the low 50s.

The forecast for Tuesday is complicated with many features in
play that will either help or hinder severe thunderstorm
development ahead of the approaching cold front. Rain Monday
night could create cold pools, where morning temps are several
degrees cooler than currently forecasted, causing CIN to be
higher than currently modeled. The showers are expected to be
scattered so confidence in where this will occur is low. Also, a
marine layer is expected to work its way into the Catskills,
Poconos and maybe even into areas near I-81 in the Twin Tiers,
as some high- res model soundings suggest. This would keep
morning temperatures cooler, increasing CIN chances. Model
guidance is also putting a lot of mid-level cloud cover over the
region during the morning hours, increasing CIN and reducing
CAPE in the afternoon.

Having said all of that, there does look like a period of
clearing occurring across NEPA west of the Poconos, extending
up into the Finger Lakes and CNY south of the Mohawk Valley.
Current modeled conditions show CAPE values reaching around 1000
j/kg in the afternoon, with 0-6km bulk shear values in the
30-40kt range. If the CIN factors from above can be limited, we
could see some discreet supercells form in the early afternoon.
Soundings show enough dry air in the mid levels that microbursts
will be possible. There are chances for small hail as well over
CNY and NEPA, with the better chances for seeing hail approach
severe criteria over Luzerne county as 700-500mb lapse rates are
approaching 7.5C and we have more CAPE in the hail growth zone.
The best chance for severe weather will be during the passage
of the cold front where storms shift from discreet to more of a
squall line, pushing through during the afternoon and into the
evening. Severe parameters are not signaling high chances for a
widespread severe weather threat, but isolated pockets along the
line will bring gusty winds given the modeled dry air in the
mid-levels.

Hydrologically, the system is modeled a little more progressive
than in previous runs, especially across CNY. PWATs will
approach 1.5in along the front, allowing for heavy downpours and
isolated flash flooding. NEPA, especially Wyoming, Lackawanna,
and Luzerne counties have a greater chance for flash flooding as
some CAMs are showing a couple rounds of heavy rain chances
within a few hours of each other.

The severe threat should end by mid-evening as the tail end of
the front should be moving out the NEPA by then. Some rain
showers may linger east of I-81 as a few weak shortwaves ripple
through the mid-levels. Even with the passage of the cold front,
temps are going to remain warm for this time of year, with lows
falling into the low to mid 50s across CNY and mid to upper 50s
in NEPA.

SPC has placed us in General Thunder as of now, given the low
confidence in severe weather chances. An upgrade to Marginal
will be possible later tonight when hopefully model guidance
has more certainty.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
350 PM Update...

The short term is looking mostly dry and a little cooler
compared to the start of the week. Upper level ridging builds in
Wednesday with a surface high moving off to the east. Weak cold
air advection aloft will cool off 850 mb temperatures a little
bit so highs will be 5 to 10 degrees cooler than Tuesday but
still above average. Ridging with zonal flow continues Wednesday
night into Thursday night with temperatures continuing to
remain above average. Forecast soundings show a subsidence
inversion present Wednesday into Thursday night so convection is
unlikely with the best chance for any showers or thunderstorms
being in the Catskills and Poconos where terrain could help
break the capping.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
350 PM Update...

The long term is looking somewhat active with the long wave
ridge axis moving east of the region opening up the northeast to
more frequent shortwaves with predominantly SW flow.
Temperatures are a little more uncertain especially for the
weekend as there are quite a few ensemble members that have
strong high pressure off of the New England coast with colder
onshore flow helping to suppress highs. There is decent amount
of spread especially since ensemble members that do not have as
strong of high pressure or dont have the marine layer push far
enough west keep highs in the low 80s. Precipitation chances
were largely kept through the long term especially in the
afternoon with day time heating and good low level moisture in
place. Also given the set up with high pressure moving off the
New England coast this weekend, an approaching front will likely
slow down and if that can slow over our region, then greater
amounts of rain would be possible.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
145 am update...

Isolated to scattered showers will move through early this
morning. Some MVFR fog and cigs is possible at most sites 9 to
13z. RME already had rain to moisten the low levels this
morning.

After 17z steadier showers and thunderstorms are expected.
Heavier rain could drop vsbys to 2sm in addition to MVFR cigs.
In general cigs will fall to fuel alternate MVFR by 21z.
SYR/RME/BGM/ITH should fall to IFR due to cigs around 21z and
continue through the night.

Winds will be mostly light early this morning. Southwest winds
at 5 to 10 kts early this morning shift to northwest this
evening.

Outlook...

Overnight toNight... Restrictions likely in lingering stratus
and fog.

Wednesday...Lingering morning clouds and restrictions possible,
becoming VFR in the afternoon.

Thursday...VFR Likely.

Friday..Mainly VFR, but late day showers/t`storms possible.

&&

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

&&

$$

SYNOPSIS...JTC/TAC
NEAR TERM...JTC/KL/TAC
SHORT TERM...AJG
LONG TERM...AJG
AVIATION...TAC