389
FXUS61 KBGM 062247
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
647 PM EDT Sat Jul 6 2024

.SYNOPSIS...
Warm and still somewhat humid this evening, with some scattered
showers and thunderstorms mainly in Central NY. Mostly clear and
seasonably mild overnight with valley fog as a surface high pressure
system moves overhead. Dry, warm and sunny weather prevails on
Sunday with slightly lower humidity levels. Monday looks to be the
hottest day of the week before it turns more unsettled with
shower and thunderstorm chances each day for mid to late week.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...

630 PM Update...

A few weak pop up showers developed over the western portion of
our region and over the Western Catskills. Updated pops using a
blend of NAM Nest, HRRR and the official forecast. Otherwise an
outflow boundary is making its way over the middle of our CWA,
not in concurrence with any showers, and possibly a lake breeze
feature. Slightly adjusted temperatures and dew points to blend
in current observations. Remaining forecast is on track at this
time.

245 PM Update...

GOES East visible satellite loop shows scattered to broken (30-60%)
cumulus cloud cover out there this afternoon. There is a lake breeze
convergence boundary moving into north-central NY which looks to
propagate east into this evening, acting as a catalyst for isolated
to sct`d showers/t`storms over portions of Central NY. Temperatures
are in the mid to upper 80s currently, with sfc dew points
dropping back a touch, now between 64-70F, which is up to 7
degrees lower than 24 hours ago (based on 230 PM NY mesonet).


MLCAPE is 400-800 J/Kg currently with LIs between -1 and -4 on the
SPC mesoanalysis. Effective layer shear is impressive at 40-55 kts
currently, but areal average soundings from the 17z HRRR are showing
dry air in the 750-550mb layer which is inhibiting any showers that
reach this level so far. The HRRR keeps this dry layer, and a weak
thermal cap around 575mb in place into the late afternoon
hours...and yet it does allow for a few thunderstorms to develop,
mainly along the remnant lake air mass boundary, which is
progressing east across our western/central CWA at this time.

Overall, sounding data shows most parameters unfavorable for severe
storms this afternoon...again owing to just too much dry air, and
weak mid/upper level lapse rates. Equilibrium levels are low,
especially for the mixed layer parcels, only reaching 20k ft
agl...and 25k ft agl for surface based parcels. Will continue to
monitor, but for now left mainly slight chance to low end chance
PoPs in the forecast across Central NY for the late afternoon &
early evening. Did include a small area of higher PoPs where the
storms are likely to roll through between now and 6 PM, along and
north of I-90 from near Syracuse to Rome.

Any lingering showers and storms should dissipate around or shortly
after sunset with skies becoming mostly clear overnight. Cross over
temperatures for valley fog formation are lower, in the low to mid-
60s over the region...but overnight lows will drip down into the
upper 50s to mid-60s. Therefore, with light winds and high pressure
in place did include patchy/areas of fog for the favored river
valley locations into early Sunday morning.

Quiet and warm weather on Sunday under high pressure. Valley fog
burns off and dissipates by 9 AM. Dew points will be lower between
60-65 in the afternoon, so it will not feel as humid out there.
Highs reach into the 80s areawide under mostly sunny skies. Much of
the same for Sunday night, with high pressure remaining overhead.
Clear skies, light winds and seasonable overnight lows in the 60s
will set the stage for more valley fog.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
255 PM Update...

High pressure overhead will promote dry conditions Monday and a
good deal of sunshine, but it will be a hot, humid day.
Dewpoints Monday will be anywhere from the mid 60s to around 70
degrees. High temperatures are expected to be in the upper 80s
to the low 90s, and heat index values can peak in the mid and
upper 90s in some valley locations. This day will be monitored
for potential heat advisories.

Clouds will start to increase Monday night as a cold front
begins to slowly approach from the west and it will be warm and
muggy. There could be enough moisture in place for a stray
shower later at night. Lows will range from the mid 60s to near
70 degrees.

The cold front is expected to continue to push east gradually
Tuesday with increasing chances of showers and thunderstorms,
especially Tuesday afternoon into Tuesday night. Tuesday looks
to remain very warm and humid ahead of the front with highs from
the mid 80s to near 90 degrees, but this will also depend on
how quickly convection gets going this day and cloud cover.
There is the potential for heat index values this day to be in
the low to mid 90s, while the Wyoming Valley may see values
nearing 100 degrees.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
255 PM Update...

Mid to late week is where uncertainty in the forecast
increases. A strong Bermuda high is expected to slow down the
eastward progress of the cold front and perhaps even stall it
out all together not too far away from the CWA Wednesday into
Thursday if the high can shift far enough westward like the 12Z
GFS depicts and most of the ensembles. This would be the
catalyst for additional showers and thunderstorms, but the wild
card is if what remains of Beryl could make it into the region.
This possible enhancement of tropical moisture can lead to the
potential of heavy rainfall and localized flooding come
Thursday, especially in urban areas and small creeks/streams.
Current guidance has Beryl moving into the southern Plains/lower
Mississippi River Valley Tuesday-Tuesday night and meeting up
with the tail end of the cold front which would help draw it
northeastward, but the question becomes where is the front and
does the tropical moisture move into the Ohio Valley and Great
Lakes or farther east toward the mid-Atlantic and Northeast.

Unsettled conditions look to persist into Friday and Saturday
with additional shower and thunderstorm chances. High
temperatures mid to late week look to generally be from the
upper 70s to the mid 80s, but convection and the potential for
heavy rainfall will make temperatures tricky. Lows are expected
to be in the 60s.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
200 PM Update

Mainly VFR conditions persist across the region through the taf
period. However, there is a chance for an isolated thunderstorm
or two in vicinity of SYR and RME as a surface convergence
boundary moves west to east. Therefore, included a PROB30 group
at these two sites from 19-23z this afternoon/evening. For the
other taf sites, it is very likely to remain dry, with chances
for any showers or t`storms only at 10-20% through sunset.

Tonight, high pressure and clear skies lead to fog developing
again mainly at ELM as they are likely to drop below their cross
over temperature during the predawn hours. Included a period of
Below Alternate Minimum restrictions in fog for ELM between
about 08-11z. The fog should lift and scatter out quickly by
mid-morning...with a return to VFR conditions areawide for the
rest of Sunday.

Outlook...

Sunday Afternoon and Monday...Mainly VFR.

Tuesday Through Thursday...Showers and thunderstorms possible,
with associated restrictions.

&&

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

&&

$$

SYNOPSIS...MJM
NEAR TERM...ES/MJM
SHORT TERM...DK
LONG TERM...DK
AVIATION...MJM