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226
FXUS61 KBGM 201704
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
104 PM EDT Mon May 20 2024

.SYNOPSIS...
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A very warm day is expected with temperatures rising well into
the 80s areawide. With dew points in the upper 50s to low 60s,
it will feel a little muggy as well. Very warm temperatures
continue Tuesday and Wednesday with isolated to scattered
thunderstorms developing in the afternoon and evening hours.
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&&

.NEAR TERM /THROUGH TUESDAY/...

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1255 PM Update...

No significant changes to the near term forecast at this time.
Scattered cumulus and thin broken cirrus clouds are over the
region. Temperatures have reached the mid-70s to low 80s as of
the latest observations...this is right on track. MLCAPE is up
to 500-1000 J/Kg, along with LIs down to -2 or -3 out there.
Therefore, cannot rule out an isolated t`storm or two over
Steuben/Yates counties and surrounding areas heading into the
early evening hours.

920 AM Update...

Only minor tweaks to temperatures, sky cover and PoPs based on
the latest satellite, observations and CAMs. Temperatures will
reach the low 80s over the higher elevations later this
afternoon with 85 to 90 in the valleys. There is some sct to
bkn, thin high level cirrus and haze moving over the region...so
this will make for a milky white sky compared to a deep blue.
irregardless it should still be mostly sunny today. There is a
slight (15%) chance for an isolated t`storm to pop up toward
sunset over Steuben/Yates counties.

330 AM Update...

With high pressure in place and upper level ridging, skies are
mostly clear with a few high clouds streaming in over the
Southern Tier. These clouds wont be affecting the development of
fog tonight as many of the deeper river valleys have already
started to fill. Fog will clear up to start another warm day
today with 500 mb heights rising to near 580 dm. With some dry
air still in the mid levels there will not be too much in the
way of fair weather cumulus with day time heating so bumped up
highs a bit for the afternoon. Given the capping as well as
drier air mixing into the boundary layer with heating, enough
instability for showers or thunderstorms will be unlikely for
most of the region outside of the higher terrain of Steuben
county.

Tonight is another mostly clear night but with the upper level
ridge axis moving east of the region, southerly return flow
strengthens. This brings in more moisture aloft so there will be
a better chance at more clouds. With increasing RH above 925 mb
there will be less efficient radiational cooling as well as
more wind in the boundary layer so fog will have a tougher time
forming.

Tuesday is another warm day with a bit more clouds and dew
points a few degrees higher as well. There is good model
agreement of a strip of Surface CAPE developing in the Finger
Lakes into CNY in the afternoon. There is not much of a trigger
but 10 meter wind fields show a surface front dropping through
the Finger Lakes and Upstate NY in the late afternoon and
evening. A few thunderstorms will likely pop up along that
surface front in the mid to late afternoon. Little shear in
place means that any storm that develops will just be typical
pop up thunderstorms with some gusty winds.
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&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
High pressure will move off the east coast Tuesday night. This
will result in a continued warming trend through Wednesday with
southwesterly winds. Most locations should rise well into the
80`s with a few locations close to 90 on Wednesday as the NBM
has caught on to the overall pattern. With dewpoints only around
60, heat index values should not be much higher. Lows generally
in the 60`s at both Tuesday night and Wednesday night. Highs
Thursday trend several degrees cooler with the frontal passage.

A frontal boundary still looks to move in later Wednesday and
Thursday to break down the ridge. Enough lift and moisture looks
present for at least some scattered showers with the frontal
passage. Instability during the afternoons surface CAPE is
currently modeled to be around 1,000 J/KG each afternoon and
evening so some thunderstorms will be possible as well. Still
some timing differences with the operational models and ensemble
guidance with the frontal timing. The instability part has been
fairly consistent on the operational models and respective
ensembles if we can get some convection in the afternoon and
evening Wednesday and or Thursday. A first look at model
soundings shows steep low level lapse rates with some mid-level
dry air as well later Wednesday. With a fair amount of shear as
well, the potential is present for some strong storms with gusty
winds and hail.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
Seeing some signal in the ensemble guidance along with the
latest 00Z 5/20 ECMWF that the front may check up not to far
south of the area Thursday night through the weekend. So while
the upcoming weekend looks mainly dry, isolated showers or
thunderstorms can not be ruled out across NE PA closer to the
front. Temperatures trend cooler with lows in the 50`s and in
the 70`s generally.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...

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Overall, VFR conditions are expected to prevail for just about
all of our TAF sites over the next 24 hours. ELM may see a short
period of fog or mist; mainly between 08-12z early Tuesday
morning. Exact extent and vsby reduction is still uncertain at
this time, but for now, limited it to MVFR restrictions here.

Otherwise, expect a mix of FEW/SCT mid level cumulus and high
thin cirrus clouds out there through this taf period. Winds are
light, and variable with a diurnal component...under 10 kts.

Outlook...

Tuesday afternoon through Thursday...Mainly VFR. Patchy early
morning valley fog possible. Also isolated to scattered
afternoon and evening thunderstorms around.

Friday and Saturday...VFR expected. Moderate to high confidence.
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&&

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

&&

$$

SYNOPSIS...AJG/MJM
NEAR TERM...AJG/MJM
SHORT TERM...MWG
LONG TERM...MWG
AVIATION...MJM