107
FXUS61 KBGM 041837
AFDBGM

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

.SYNOPSIS...
Humidity will be increasing today with warm and muggy conditions
expected into this evening. 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/...
1235 PM Update...

Forecast remains on track this afternoon. A mix of sun and
clouds out there, with temperatures rising into the upper 70s to
mid-80s as of the midday observations. It is becoming quite
humid, as surface dew points rising into the mid-60s to lower
70s. MRMS radar shows a few scattered showers out there, now
exiting Sullivan County (NY) and popping over Bradford county.
No lightning yet, but MLCAPE is up to 250 J/Kg and SB LIs are
just below 0 now...so isolated to sct`d thunderstorms are still
expected to develop later this afternoon and evening.

1000 am update...

Minor adjustments to the cloud cover, PoPs and temperatures
through the near term period based on latest satellite, radar
and other observations. Latest CAMs such as the 12z HRRR and 06z
3km NAM were also incorporated into the official forecast.
Moisture, and surface dew points are increasing over western
NY/PA at this time. SPC meso-analysis shows this is where
surface based and mixed layer CAPE is building most effectively
this morning. Overall, it appears some isolated to sct`d
thunderstorm activity will develop this afternoon and evening,
mainly from the Southern Tier down across portions of NE PA.
Exact timing and location of any thunderstorms is uncertain at
this time...however these could linger in a few locations
through sunset and into the late evening hours. This will be
watched closely. Guidance shows upwards of 500 J/Kg of MLCAPE
later this afternoon and evening, along with about 40 kts of
0-6km bulk shear and pwats around 1.8" so a few stronger storms
with gusty winds and torrential downpours cannot be ruled out.

630 am update...

Updated QPF amounts tonight into tomorrow as showers look a bit
more widespread in the 6Z model runs. Also updated chances of
precipitation for that reason. Showers are popping up on MRMS
this morning so some higher chances of showers were introduced
to the Southern Tier and NEPA through 10AM.

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 /SATURDAY THROUGH SUNDAY 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 /MONDAY 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 /19Z THURSDAY THROUGH TUESDAY/...
2 PM Update

Mainly VFR expected this afternoon and evening over the region.
There could still be an isolated shower or thunderstorm
especially for AVP or BGM; included a PROB30 group in the tafs
for these two sites between about 20z to 01z this afternoon and
evening. Elsewhere, showers or t`storms are not expected at
this time.

Tonight, high pressure builds in at the surface with largely
calm winds. It looks like there will be a few showers and
thunderstorms across CNY into NEPA into the overnight but they
will be spotty (so not included in the tafs). With some clear
skies between the showers and high surface humidity values, fog
chances are rather high especially for ELM. Lower chances exist
at BGM, ITH, RME and AVP that will be dependent on if any rain
can fall near the airports. Generally included tempo groups for
MVFR Fog/Mist, except IFR at ELM between the hours of 07-11z
early Friday morning. Any fog/mist burns off by mid-morning
with a likely return to VFR conditions. However, additional
showers and t`storms will develop and move across the forecast
area on Friday.

Outlook...

Friday afternoon 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...AJG
NEAR TERM...AJG/MJM
SHORT TERM...ES
LONG TERM...ES
AVIATION...AJG/MJM