522
FXUS61 KPBZ 061224
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
824 AM EDT Sun Oct 6 2024

.SYNOPSIS...
Showers and thunderstorms will be possible later this afternoon
and through the evening with a passing cold front. Noticeably
cooler temperatures and dry conditions are expected Monday and
through the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
KEY MESSAGES:

- Unseasonably warm with increasing humidity during the
  afternoon.
- Strong to severe thunderstorms possible later this afternoon
  and into the evening.
-------------------------------------------------------------------

Made some minor tweaks to temperatures to account for some
unexpected low and mid level cloud cover pass through the area.
Timing of the front today is still on track and did not need any
adjustments.

Warm, moist advection will ramp up ahead of an
approaching front today, which is progged to cross the region
later this afternoon and through the evening. Joint
probabilities of effective shear of 30kts and 500J/kg peak
around 100% at 5PM this afternoon north and west of PGH,
decreasing from there on out. Bumping up CAPE thresholds to
1000J/kg drops probabilities down to around 60% at the same
time.

Ample deep layer shear and cold mid-level temperatures will
support both large hail and damaging winds as storms rapidly
grow upscale and evolve into a line with bowing segments. There
will be a very narrow window of an hour or two early in storm
development, where forecast hodographs look more favorable for
tornado potential, if they can remain discrete. That said LCLs
are forecast to be rather high, which will limit potential.

The severe weather threat should rapidly decrease by 00Z and
lingering thunderstorm/precipitation threats should clear the
Laurel Highlands into the WV mountains before 10 PM with the
passage of the cold front and the loss of surface heating.

In the wake of the front, overnight temperatures will fall to
near average.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
KEY MESSAGES:

- Dry conditions resume, with much cooler temperatures.
-------------------------------------------------------------------

A much cooler air mass will return to the area behind the
mentioned front with temperatures dropping some 20 degrees for
highs on Monday, ending up in the low 60s. A slight moderation
in temperatures is likely into the middle of the week with
increasing heights, with dry conditions continuing as surface
high pressure settles over the region.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
KEY MESSAGES:

- Dry weather continues with temperatures trending up towards
  the end of the week.
-------------------------------------------------------------------

Dry conditions will continue the remainder of the week as high
pressure remains the dominant feature. The limited cloud
coverage will likely lead to large diurnal temperatures swings
during the week. Models continue to show a signal toward low
temperatures falling into the 30s by Friday morning with a few
cooler solutions within the ensembles hinting at a least a few
pockets of frost, with the sheltered Canaan Valley of West
Virginia almost certain to see a deep hard freeze.

Temperatures will bounce back to above normal as a large, broad
central CONUS ridge shifts east towards the end of the week and
into next weekend.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
High confidence in VFR conditions through 18z today as high
pressure slowly shifts east of the region. Surface winds out of
the SSW will increase aft 15z as pressure gradient tightens
ahead of an incoming cold front.

Scattered to potentially numerous showers and thunderstorms are
favored to develop along the frontal boundary and rapidly move
SE between 21z-04z. Peak intensity of thunderstorms could drop
visibility to 1 mile or less and contain gusty wind in excess of
40kts, but probability of terminal impact for those higher end
values is too low for mention.

Limited moisture ahead/behind front will
keep ceiling impacts short in duration, though notable cold
advection should aide in a stratocu layer developing as it
traverses warmer Lake Erie waters.

.Outlook...
There is a potential (up to 60%) for MVFR stratus reaching as
far south as KPIT in the post-frontal environment early Monday
morning (after 06z) and lingering into the early afternoon.

Otherwise, VFR conditions are highly likely Monday night through
much of the rest of the week under the influence of high
pressure. Cooler temperature and light wind nights may result in
brief periods of morning river valley fog.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.

&&

$$

SYNOPSIS...Bookbinder
NEAR TERM...Shallenberger
SHORT TERM...Bookbinder
LONG TERM...Bookbinder
AVIATION...Frazier/Shallenberger