-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 231114
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
714 AM EDT Tue Apr 23 2024

.SYNOPSIS...
Dry and seasonably warm weather is expected most of today as
high pressure moves east of the area. Showers will return late
today and tonight, and continue through part of Wednesday, with
a crossing cold front. A warming trend is then expected late
this week through the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
KEY MESSAGES:

- Dry and warmer today
- Wind gusts around 25 mph this afternoon
------------------------------------------------------------------

Made a morning update to adjust the temperatures and dew points
to the current trends. Did bump temps up a degree into the
afternoon to adjust more to the rapid warming this time of year
and the models poor adjustment to the transitioning season.

Previous discussion...Continued with the frost advisory through
9 AM, with several more sheltered locations reporting
temperatures in the lower to mid 30s.

Otherwise, shortwave ridging will slide east of the area this
morning, as a shortwave trough and surface cold front approach
from the Midwest. Clouds will increase through the day in warm
advection ahead of the shortwave.

A tightening surface pressure gradient ahead of the front, and
mixing, will result in wind gusts of around 25 mph by this
afternoon. Low dew points are also expected, and will highlight
this in the fire weather forecast.

Shower chances will increase by late afternoon, mainly NW of
Pittsburgh, as the front approaches. Increased temperatures a
couple of degrees above guidance in some locations, with the
warm advection and mixing expected today.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
KEY MESSAGES:

- Showers return tonight with a crossing cold front
- Few showers possible Wednesday with a secondary trough
- Frost possible Wednesday night
- Dry and warmer Thursday
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Showers will overspread the region through the evening as the
shortwave trough and surface cold front cross the Upper Ohio
Valley region. Some jet support will also enhance the ascent as
the front crosses. Rainfall amounts are expected to range from a
tenth to a quarter of an inch for most areas.

Scattered showers will continue through part of Wednesday as the
upper trough axis crosses, and a secondary surface trough tracks
across the region. Any remaining showers should end by mid to
late afternoon as the troughs exit, and surface high pressure
begins to build across the area from the north. Clearing skies
and temperatures in the upper 20s to mid 30s will result in a
frost and freeze potential Wednesday night and Thursday morning.

The high is expected to be centered across southern Ontario
Thursday, moving east to New England Thursday night. This will
result in dry weather across the Upper Ohio Valley region, with
slightly warmer temperatures.

&&

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

- Much warmer through the weekend
- Showers return Friday night into Saturday
- Showers and thunderstorms with a Monday cold front
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Model ensembles indicate ridging, warm advection, and rising
1000-500mb heights will result in dry and warmer weather on
Friday. The ridge will shift east of the area Friday night and
Saturday, as a shortwave trough embedded in southwest flow aloft
crosses the region. Showers and possible thunderstorms will
return with the approach and passage of the wave.

The ridge is then progged to become reestablished across much
of the Eastern CONUS through Sunday night. Dry weather is
expected most of the period from Saturday night through Sunday
night, through diurnal instability could be sufficient for
isolated to scattered showers and thunderstorms.

Rising 1000-500mb heights, and 850mb temperatures around 14 deg
C, should result in highs in the upper 70s to mid 80s by Sunday.
This warmth should continue through Monday.

The ridge is expected to shift eastward on Monday, as a
shortwave trough and associated surface cold front approach from
the Midwest. More widespread shower and thunderstorm chances are
expected with the approach and passage of the front.

&&

.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
VFR conditions are anticipated through the day.

Wind gusts will increase through the post-dawn morning hours.
Increase mixing will work to bring stronger winds aloft to the
surface. Wind gusts of 20 to 30 mph are expected through the
afternoon hours.

Light rain showers are possible toward the end of the TAF
period. Additionally, following the onset of rain, cigs should
lower to MVFR.

Wind will weaken somewhat after dark, however gusts of 15 to 25
mph remain possible.

.Outlook...

Widespread MVFR to potential IFR (DUJ/FKL) conditions are
expected to increase between 09Z to 12Z Wednesday with the
passage of a cold front.

Cig improvements will likely develop late evening Wednesday with
incoming dry, cold air in the wake of the front.

The probability of showers and isolated thunderstorms increases
Saturday.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Frost Advisory until 9 AM EDT this morning for PAZ008-009-
     014>016-022-029-031-073>078.
OH...None.
WV...Frost Advisory until 9 AM EDT this morning for WVZ021-509>512.

&&

$$

SYNOPSIS...WM
NEAR TERM...WM/Shallenberger
SHORT TERM...WM
LONG TERM...WM
AVIATION...Shallenberger/22