451
FXUS61 KBGM 080600
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
200 AM EDT Wed May 8 2024

.SYNOPSIS...
Sunny and dry weather expected this afternoon but a warm front
moving in tonight brings the threat for showers and
thunderstorms after midnight. Tomorrow, a cold front moves
through with the threat for a few isolated strong storms in the
late morning and early afternoon. Cooler and showery weather is
expected late week into the weekend.

&&

.NEAR TERM /THROUGH TODAY/...
935 PM update...

Again, the main change with this forecast was to the
temperatures and dew points. Under partly cloudy skies,
temperatures have fallen a bit since the last update, now in the
50s and 60s. Cloud cover will increase from the west over the
next few hours and that should slow down the cooling. Slight
adjustments were made to PoPs based on some of the 00z guidance
that has come in. Otherwise, we are awaiting the showers that
are slowly creeping through western NY and PA. Models continue
to show some limited instability, though elevated, so low
chances for thunder were kept in the forecast.

630 PM update...

Conditions are a bit drier than expected as dew points are low.
Temperatures are still mild though, leading up to a pleasant
evening. Minor changes were made to temperatures, though
slightly more changes were needed for dew points. Sky cover was
also touched up as a layer of high clouds are moving through
the area. As for the rest of the forecast, it all was doing well
and needed no additional changes.

230 PM update...

Sunny skies with a pocket of dry air moving through aloft
evident in water vapor imagery has caused dew points to fall
with day time mixing. Winds are fairly light but relative
humidities have fallen to around 30 percent for much of the
region. Deeper moisture is trying to make its way in from
central PA so NEPA is fairing a bit better with RH this
afternoon. Tonight, a warm front lifts in with clouds increasing
as well as a threat for some rain showers and elevated
thunderstorms. Forecast soundings do get up near 1000 J/kg of
elevated CAPE and with 50 knots of 0-6 km shear, there is a
small threat for some hail though hail size overnight should
stay sub severe with CAPE being skinny.

Tomorrow is looking a bit more interesting as there is a weak
elevated mixed layer moving through in the morning to early
afternoon where mid level lapse rates get up over 7 C/km with
0-6 km shear near 70 knots associated with a jet streak moving
overhead. Some of the CAMs do get to have over 1000 J/km of
surface based CAPE in the afternoon with little capping. Despite
there being good lapse rates and weakly capped surface based
CAPE is the lack of a trigger at the time we have the
ingredients in place for severe storms. There is a 500 mb
vorticity wave moving through northern NY so right now the NY
thruway corridor has the best chance at seeing a stronger storm
in the afternoon with large hail and wind being the main threat
if a storm can get going. Decided to keep at least a slight
chance of thunderstorms in the grids for tomorrow afternoon as
any outflow from storms farther away could trigger storms to
develop later in the day despite no mid level triggers.

Wednesday night is looking cooler with a cold front dropping
south and skies clearing and dry air advecting in at lower
levels of the atmosphere. With stronger boundary layer winds,
temperatures were not lowered below model guidance yet but if
there can be some decoupling, good radiational cooling will
cause temperatures to fall below forecasted values.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
Low pressure will track eastward from the Ohio Valley to the
east coast Thursday and Thursday night. Enough lift and moisture
will overrun a warm front to result in the development of
showers. The coverage of showers is actually a bit more
uncertain and will depend on how convection evolves over the
next couple of days. Some of the modeling is trending south with
this 12Z cycle. That is an entirely plausible outcome with
convection involved. Still the bulk of ensemble data shows about
half an inch of QPF with locally higher amounts in NE PA and
the Southern Tier of NY. Clouds and showers will likely keep
temperatures in the 60`s during the day then only fall into the
50`s at night.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
The previously mentioned low pressure system looks to linger on
Friday keeping some showers around. A broad mid-level trough
will continue to be over the region with several additional weak
cold fronts and disturbances to keep some chances of showers
around most days with the highest chances this weekend. Chilly
as well with lows in the 40`s and highs getting into the
50`s/60`s. Actual timing of the disturbances is still highly
uncertain.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions prevail, with plenty of high clouds across the
region. Scattered showers and isolated thunderstorms associated
with an upper level disturbance and surface trough are moving
into western NY and PA. 06Z HREF members and subsequent HRRR
runs suggest the bulk of the showers will attempt to avoid
ITH/ELM/BGM, but radar trends show increasing thunderstorms
upstream over far SW NY and NW PA. So, will keep in the threat
of showers, some heavier with visibility restrictions. Guidance
has trended more optimistic with ceilings as the showers roll
through, and this is supported by upstream observations as well.
Kept most sites out of fuel alt levels with this set of TAFs.

Showers will move out shortly after dawn, with VFR conditions
returning. West winds will increase later this morning and
afternoon, with gusts around 25 knots possible.

Additional showers or thunderstorms are possible this afternoon
as another upper level disturbance rolls across northern NY, and
a weak cold front pushes southward into the area. A few stronger
thunderstorms are possible, mainly after 20Z. Coverage is
questionable, and for now left thunder out of the TAFs, though
PROB30s may be added later for SYR and RME.

Outlook...

Wednesday night through Sunday...Periods of showers with some
restrictions as multiple disturbances pass through the region,
especially Thursday-Friday.

&&

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

&&

$$

SYNOPSIS...AJG
NEAR TERM...AJG/BTL
SHORT TERM...MWG
LONG TERM...MWG
AVIATION...ES/MPH