506
FXUS61 KBGM 040636
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
236 AM EDT Thu Jul 4 2024

.SYNOPSIS...
Humidity will be increasing today with a hot and muggy
afternoon expected for Independence day. A few scattered showers
and thunderstorms develop in the Southern Tier into NE PA this
afternoon and overnight that could impact some firework
displays. Muggy conditions last into Friday with continued risk
of thunderstorms into the weekend.

&&

.NEAR TERM /THROUGH FRIDAY/...
230 AM Update...

The showers early this morning across the Finger Lakes into the
Tug Hill have been spotty so precipitation chances were lowered
through the morning hours. Observations across the region show
southerly flow with higher dew points advecting in from the
south so this afternoon will feel muggy as those dew points rise
to near 70. The NBM was being a little aggressive with the
afternoon dew points so a couple of drier models were blended
in.

Given the forecast soundings across the Southern Tier into
NEPA, chances of precipitation were raised and the wording
changed to coverage rather than uncertainty as there is plenty
of surface based CAPE and not much cin.

Tonight, the HRRR wants to have more widespread showers and
thunderstorms but it is an outlier right now. Looking at the
HREF most of the CAMs have surface high pressure building in and
keeps the strongest warm air advection to the south. It looks
like what triggers the nocturnal convection in the HRRR is the
development of a 500 mb shortwave with an MCS that forms today
in the central plains.

Friday is looking a little warmer than today with better CAPE
across the area. There will be good shear in place with forecast
hodographs in the HREF members with 40 knot mean 0-6 km shear.
Low level shear is on the lower side with 0-1 km shear around
15. There is a lot of difference in the directional shear with
the CAMs in our region late in the day and that is likely tied
to the uncertainty in whether an MCV can develop with an MCS in
the central plains today into tonight. This could lead to more
turning in the low levels and potentially a bigger risk for
severe storms if an MCV develops and actually moves into our
region. Right now with straighter hodographs and most of the
shear above 3 km, the severe risk is more limited to wind and
low level lapse rates are not great. CAPE is also looking long
and skinny with precipitable water values over 1.5 inches so
flash flooding is possible if any locations can get multiple
rounds of convection over the next couple of days.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
305 PM Update...
Our next chance of showers and thunderstorms will focus on
Friday night into Saturday. There is some uncertainty for
whether a few stronger cells may be involved, as well as locally
heavy rainfall.

Friday a surface low in the western Great Lakes deepens and
moves east with a warm front lifting into the region. The warm
air advection looks weak initially so despite some lift, it does
not look like enough forcing is in place to get much more than
a few isolated to scattered thunderstorms going during the day
Friday. However, it will be quite warm and humid, with heat
index values reaching into lower-mid 90s for much of the area,
and especially in the Wyoming Valley of PA.

As was already mentioned in the previous version of the
discussion, better dynamics move in Friday evening and
overnight with better lift as another warm front moves in with
better chances of showers and thunderstorms. Shear looks to be
good overnight with near 50 knots of 0-6 km shear but forecast
soundings show stable air near the surface and elevated CAPE
staying below 1000 J/kg with a low equilibrium level so severe
thunderstorms are unlikely overnight. Precipitable water values
will be over 1.5 inches and could approach 2 inches so heavy
rainfall will be likely with showers and thunderstorms that do
develop. Storm motions will be 20 to 30 knots so that will limit
residence time of the higher rain rates but any training could
lead to isolated/localized flash flooding potential Friday
night into Saturday morning. The nocturnal timing of this
frontal system brings into question how much instability can
actually be realized, but the dynamics may provide the boost
that would be needed.

The surface low passes north of the Region Saturday with a
front dragging through NY and PA. Models are trending a bit
faster with the exit of the front which may allow much of the
area to actually dry out after the Friday night-early Saturday
activity. That said, still some uncertainty in timing and thus
we still hang on to some chances of showers and storms
especially east of I-81. Pretty confident though that we dry out
Saturday night as high pressure builds into the region.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
305 PM Update...
After a quiet Sunday, we may enter a more active pattern towards
the middle of next week as heat and humidity interact with
passing waves.

High pressure visits during the second half of the weekend with
a pleasant day Sunday; highs of mid 70s-mid 80s with
comfortable dewpoints.

Heat and humidity build quickly Monday into Tuesday via
southwest flow on the edge of a ridge. With upper jet in
vicinity and likely passing shortwaves, there will probably be
triggers for convection Tuesday-Wednesday with heat and humidity
available as fuel plus shear from the strong flow aloft.

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
A cold front is moving in with some showers near SYR and RME.
These will move into SYR and RME bringing some MVFR cigs into
the mid morning hours. These showers will become less widespread
as they drop south into ITH, ELM, and BGM later this morning but
some brief MVFR cigs is possible so tempos were added to ELM
and BGM while ITH has a better shot at longer durations of lower
cigs. AVP will not have the front reach them until this
afternoon where a few showers and thunderstorms could pop up
towards 0Z.

As we head towards 6Z tonight, fog will be developing but
restrictions at ELM should hold off until after 6Z.

Outlook...

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

Sunday and Monday...Mainly VFR.

&&

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

&&

$$

SYNOPSIS...AJG
NEAR TERM...AJG
SHORT TERM...MDP
LONG TERM...AJG/MDP
AVIATION...AJG/MPK