FXUS61 KBGM 230140

Area Forecast Discussion
National Weather Service Binghamton NY
940 PM EDT Mon Jul 22 2024

Showers and thunderstorms will continue through the overnight.
The active weather pattern will continue into the middle of the
work week with scattered showers and thunderstorms around each
day. Conditions become drier and warmer later in the week and
into the weekend as high pressure builds over the region.



Thunderstorms have pretty much decayed into an area of
stratiform precipitation late this evening. While this
precipitation has trended lighter the potential for heavier
showers to form overnight is still present. Updated pops and
thunder chances through the overnight. Also, removed any mention
of fog given the considerable overcast with the late evening

A favorable corridor of instability overlapped with a warm
frontal boundary to produce several rounds of showers and
thunderstorms this afternoon and evening. Eventhough PW values
are only around 1.6 inches rainfall rates have been quite
impressive, around 2 inches per hour in spots. Some flash
flooding has occurred in Bradford and Steuben counties where
repeat rounds of thunderstorms have moved through. Forecast QPF
was increased dramatically into the evening hours to account for

With the loss of daytime heating the lingering showers should
slowly weaken this evening. However, mesoscale modeling is
showing another round of showers and thunderstorms heading into
the region overnight. Given already saturated ground some
additional flooding is possible overnight.

230 PM Update...

Storms developing across the Twin Tiers and NE
PA will move generally east-northeastward now and through the
evening hours. These storms and showers are developing in a
moist environment, with PWAT values between 1.5 to 1.75 inches.
Any of these storms and showers could produce heavy downpours,
and could cause localized flash flooding. CAMs have generally
sped up the timing, but they`re still a couple hours behind with
onset of storms. Additionally, storms aren`t stalling too much,
but there could be some backbuilding and training of storms and
showers that could lead to localized flash flooding. From a
shower that lasted about 20 minutes over the office, it produced
almost a half inch of rainfall, providing confidence that these
showers and storms are capable of producing a lot of rainfall
in a short amount of time.

Any storms will taper off after sunset, where showers will
prevail into the early morning hours of Tuesday. Patchy fog will
likely develop across the area after showers taper off, and lift
soon after sunrise. For Tuesday, scattered storms expected in
the afternoon, with temperatures in the low to mid 80s.


For Wednesday, upper level trough will be moving into the Great
Lakes region and becoming positively tilted as it runs into the
large upper level anticyclone off the east coast. Since this
trough is slow moving and the upper level ridge is holding
steady, there will continue to be modest amounts of 0-6 km shear
Wednesday. Bulk shear magnitudes are running around 30 knots
Wednesday afternoon. ML CAPEs are projected to be 1000-1500 J/KG
on the NAM12 in western and parts of central NY with lesser
CAPE farther south and east. The GFS as usual has less CAPE
under 1000 J/KG. CAMs for Wednesday are showing a batch of
showers and a few storms skirting northeast PA in the morning
with a possible MCV hence the lower CAPE. Scattered
thunderstorms develop in the afternoon farther north into
central NY as per CAMs. This goes along with a short wave riding
northeast around the base of the Great Lakes Trough. I wouldn`t
be surprised if our area ends up in a marginal risk but it is
indeed a "marginal" set up for severe at Day 3. Any convection
that forms will last into the evening before tapering off
overnight into Thursday morning.

For Thursday, Great Lakes trough presses east and pushes a cold
front through central NY during the late morning/early afternoon and
northeast PA by evening. With the upper level trough really making a
move to the east pressing more into the ridge aloft, bulk wind shear
values between 0-6 km get up to over 40 knots. Instability will be
modest with sfc based CAPEs at or above 1000 J/Kg. There is more
uncertainity as to the timing with this front and how much
instability will be available. But there is higher confidence in
strong enough shear for severe thunderstorms. So for now we will
have high POPs for showers and thunderstorms most of Thursday given
uncertainty in timing of front.

Then for Thursday night, cold front clears northeast PA as per GFS
and Euro with high pressure building into the Great Lakes. The GFS
is dry with the Euro showing some residual low-level moisture and a
few showers. We will stick with NBM for now given uncertainities.
The amount of rain as per Euro would be very light anyway.


For Friday, high pressure builds across the region with northwest
flow aloft downstream from an upper level ridge over the upper
Midwest. This should lead to mostly dry conditions. Again the 00z
Euro continues to hold onto low-level moisture Friday morning but
again it would be light and spotty precipitation.

For the weekend, high pressure builds in aloft above a surface high
with fair weather and increasing temperatures. By Monday, models
diverge some but overall it will be very warm and humid with a
southerly flow in place. We will stick close to NBM for this period
given model uncertainities.


Several rounds of showers and isolated thunderstorms are
expected this evening into the overnight. Some of these will
result in MVFR visibilities from time to time. Ceilings should
lower to the MVFR level overnight even outside of the showers.
Showers should end by 12Z Tuesday for all TAF sites with MVFR
ceilings lifting soon after. Additional isolated to scattered
showers and thunderstorms are possible Tuesday afternoon but
uncertainity with coverage and timing is still present.


Tuesday night through Thursday...Several rounds of showers and
thunderstorms with associated restrictions. Activity will
generally be dependent on daytime heating, with best chances of
rain and thunder during afternoon-evening hours.

Friday and Saturday...VFR conditions expected as high pressure
builds in.






NWS BGM Office Area Forecast Discussion

Random Fact

Weather Terms

Enhanced Fujita Scale or EF-Scale - A scale of wind damage intensity in which wind speeds are inferred from analysis of wind damage. All tornadoes and most other windstorms are assigned a numerical rating from this scale according to the most intense damage caused by the storm. EF0 (weak) 6585 mph, light damage EF1 (weak) 86110 mph, moderate damage EF2 (strong) 111135 mph, considerable damage EF3 (strong) 136165 mph, severe damage EF4 (violent) 166200 mph, devastating damage EF5 (violent) >200 mph, incredible damage