PBZ issues Area Forecast Discussion (AFD) at Sep 1, 2:32 AM EDT
153
FXUS61 KPBZ 010632
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
232 AM EDT Tue Sep 1 2026
.WHAT HAS CHANGED...
A slight risk has been added for the forecast area for Tuesday
and Tuesday night. A slight risk remains in effect for
Wednesday. Heat risk looks to be the greatest on Wednesday but
storms and cloud cover complicate that.
&&
.KEY MESSAGES...
1) Additional shower and thunderstorm chances at times through
late week, with some possibility for severe storms.
2) Heat and humidity build through mid week
&&
.DISCUSSION...
KEY MESSAGE 1...
A ridge is expected to build eastward from the Central CONUS
through mid week. The highest 500mb heights are progged to be
across the Lower Ohio Valley region on Wednesday. As the ridge
builds eastward, shortwaves are expected to track along the
northern/northeastern periphery of the ridge, crossing the lower
Great Lakes/Upper Ohio Valley region. Occasional shower and
thunderstorm chances are expected as these waves cross, one
tonight (mainly north of the forecast area,) with another
possible later Tuesday. There remains uncertainty in the
placement and strength of the ridge, and the resulting track of
any shortwaves on the northern periphery.
There is a conditional potential for severe storms on Tuesday.
ML CAPE increases to between 2000 and 3000 J/kg by late
afternoon, with veering in the low levels. An initial warm
layer aloft could limit convection, though a possible shortwave
passage in the afternoon could trigger thunderstorms. This
scenario remains uncertain due to the reasons mentioned above,
though if storms are able to develop severe weather will be
possible.
The day with the lowest potential for showers and thunderstorms
appears to be Wednesday, when the ridge is progged to be the
strongest across the Ohio Valley region. Current indications
are the ridge should begin to break down late Wednesday and
Thursday, as a shortwave and surface cold front approaching. The
potential for severe storms will also increase by Wednesday
evening, increasing again on Thursday as convection increases in
diurnal heating along the slow moving front. Increasing NW flow
aloft should result in increased shear and diurnal instability.
The potential continues for severe storms into Thursday. The
latest ML guidance indicates the increasing severe potential,
especially late Wednesday and Thursday. Depending on how fast
the front drifts south, this potential could continue for at
least southern portions of the area into Friday. Dry weather
should return by the weekend as the front exits and high
pressure builds in.
KEY MESSAGE 2...
Rising 500mb heights with the building ridge should result in
warmer temperatures each day through mid week, with the heat
peaking Wednesday when the ridge is strongest across the Upper
Ohio Valley region. Most locations outside of the higher terrain
should reach the 85 to 90 degree range on Tuesday, though there
is a continued potential for convection and/or patchy cloud
cover which could affect daytime highs. The heat should peak
Wednesday, as highs in the upper 80s to lower 90s for most
areas. The combination of heat and humidity should result in
heat index values in the mid to upper 90s Tuesday and Wednesday.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A VFR forecast is mainly in effect through the period. Overall,
westerly to southwest winds are expected up to 10 knots through
the day. Showers and thunderstorms are possible through the day
with mainly being isolated. The main threat appears to be in the
evening and overnight Tuesday into Tuesday night. Where showers
and storms disrupt the terminals, there will be lapses in flight
conditions through the period. Have put in PROB30s to account
for the continued uncertainty. Locations such as ZZv may miss
out on the convection completely.
Outlook...
Shortwave movement along the northern periphery of the ridge
could create short periods through the week where
showers/thunderstorms may occur. Due to difficulties modeling
these features, timing/coverage of storm potential may be
difficult until 6-12 hours before arrival and cause larger-
than-normal fluctuations in TAF storm timing. Additionally,
storm environments may be conducive to gusty, erratic winds plus
heavy downpours that could contribute to restriction
development.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
$$
DISCUSSION...Shallenberger
AVIATION...Frazier/Shallenberger
Source: PBZ issues Area Forecast Discussion (AFD) at Sep 1, 2:32 AM EDT (https://mesonet.agron.iastate.edu/p.php?pid=202609010632-KPBZ-FXUS61-AFDPBZ)
---------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!