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000
FXUS61 KPBZ 231411
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1011 AM EDT Tue Apr 23 2024

.SYNOPSIS...
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Dry, warm weather is expected today with marginal fire weather
concerns. A crossing cold front will increase precipitation
chances tonight and early tomorrow. A warming trend is expected
to close out the week.
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&&

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

- Dry and seasonably warm weather with wind gusts up to 30mph
  will result in marginal fire weather concerns today.
- Showers arrive overnight with a passing cold front.
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Shortwave ridging will continue its eastward progression as a
shortwave trough moves in through the near term. Accelerated
flow is expected in an increasing gradient. Stout mixing up to
~800mb is expected to allow wind gusts up to 20 to 30mph during
the day today.

As of 10am, the mixing is already over-performing most
guidance, hence, opted to increase the temperatures into the day
today towards the 90th percentile and lower the dewpoint towards
the 10th percentile as the atmospheric profile slowly taps into
a dry cap.

Low relative humidities and heightened wind will come together
to create marginal fire weather concerns today across the
forecast area. A fire weather SPS is in effect in West Virginia
through 8pm to highlight the threat.

Shower chances increase in pre-frontal convergence and along a
passing cold front this evening and overnight tonight. Precipitation
totals have trended down slightly with the latest update. There
is only about a 30% chance of exceeding a quarter of an inch
along I-80,with roughly a 15% to 25% chance elsewhere. This
means Pittsburgh will likely not exceed its all-time April
rainfall with this event.
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&&

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

- Few showers possible Wednesday with a secondary trough
- Frost possible Wednesday night
- Dry and warmer Thursday
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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.
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&&

.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 /14Z 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...
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PA...None.
OH...None.
WV...None.
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&&

$$

SYNOPSIS...Milcarek
NEAR TERM...Milcarek
SHORT TERM...WM
LONG TERM...WM
AVIATION...Shallenberger