144
FXUS61 KPBZ 191135
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
735 AM EDT Fri Jul 19 2024

.SYNOPSIS...
Dry weather will continue through the weekend for much of the
area under high pressure. The main exception will be Saturday,
where scattered showers and thunderstorms are expected mainly
south and east of Pittsburgh with a crossing wave of low
pressure. Periodic shower and thunderstorm chances are expected
next week.

&&

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

- Mainly dry and less humid today

__________________________________________________________________

Adjusted some of the morning valley fog areas in the latest
update. Otherwise, dry weather is expected for most of the area
today as surface high pressure builds across the Upper Ohio
Valley region. An upper trough will exit the region this
morning, with rising 1000mb-500mb heights through the day. This
should result in high temperatures a couple of degrees warmer
than yesterday, but still near seasonable levels. Dew points
will remain in the 50s today, resulting in comfortable humidity
levels.

A late afternoon shower is possible across the higher terrain
area of Tucker county WV with diurnal instability, though this
potential is low.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
KEY MESSAGES:

- Dry weather for much of the area through Sunday night

- Scattered showers and thunderstorms possible Saturday mainly
  south and east of Pittsburgh with a wave of low pressure

_________________________________________________________________

Dry weather is expected tonight as surface high pressure builds
further across the Upper Ohio Valley region. A shortwave /
vorticity maximum embedded in southwest flow aloft is expected
to track northeastward across the lower Ohio Valley to the Mid
Atlantic region on Saturday. This could spark scattered showers
and thunderstorms for areas south and east of Pittsburgh.
Instability is expected to remain minimal, with general rainfall
amounts a quarter of an inch or less where these showers occur.
Elsewhere, dry weather will continue under surface high
pressure.

The shortwave will quickly exit the region Saturday evening,
with dry weather areawide under high pressure. The high will
then maintain dry weather through Sunday night.

Temperatures should begin to increase a couple of degrees
Saturday, outside of any precip, with warm advection under
southwest flow. This trend will continue Sunday, with rising
1000mb-500mb heights.

&&

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

- Periodic shower and thunderstorm chances increase through the
  week

- Above average temperatures expected
  ________________________________________________________________

Model ensembles indicate a trough will deepen across the Central
CONUS early next week, before drifting eastward by mid to late
week. This trough should approach the Upper Ohio Valley region
by Thursday. Southwest flow ahead of this persistent trough
will result in warm, moist advection across the region.

A series of shortwaves embedded in the southwest flow, and
diurnal instability, will lead to periodic shower and
thunderstorm chances across the area. At this time, it appears
the more significant shortwave passages will be Wednesday and
Thursday, where highest POPs are focused in the forecast.
Uncertainty still exists though in the exact timing and coverage
of the rain.

Above average temperatures are expected through the period, with
increased humidity levels as well.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Patchy river fog this morning gives way to widespread VFR and
light winds which prevail throughout the TAF period. A few/sct
cu field could develop during mid/late morning hours, but with
abundant dry air evident in the 12Z PIT sounding the expectation
is that cu would be short-lived, dissipating by the afternoon.

.Outlook...
VFR conditions are expected through the weekend as a ridge axis
builds over the Great Lakes.

&&

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

&&

$$

SYNOPSIS...WM
NEAR TERM...WM
SHORT TERM...WM
LONG TERM...WM
AVIATION...Cermak