-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 160354
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1154 PM EDT Mon Apr 15 2024

.SYNOPSIS...
Warm weather will start the week with values some ten degrees
above normal. Unsettled weather returns Wednesday and Thursday,
with cooler air arriving for the weekend.

&&

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

- Temperatures will remain above average; Tuesday is most likely
  dry area-wide.
-----------------------------------------------------------------

Tame weather is expected in the near term with a surface high pressure
ridges moving overhead. Calm to light winds overnight and clear
skies will drop temperatures efficiently, but still a few
degrees above average given antecedent warmth.

Tomorrow, calm weather will continue. Abrupt morning temperature
increases are expected the shallow nocturnal inversion breaks.
Mixing into a dry, warm profile led to the upward adjustment of
high temperatures and a nudge down of daytime dewpoints. Though
relative humidities may drop into the 30s and 20s, there are no
fire concerns at this time with wet antecedent conditions and
calm winds. High clouds will approach in the evening, though an
earlier approach could limit mixing a tad, should it
materialize. Low PoPs were hoisted in southeast Ohio and
northern West Virginia with weak mid- level PVA.

&&

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

- Rain chances return late Tuesday through Thursday
- Temperature remains above average
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The weather pattern thru mid-week will be transitional, with
today`s upper ridge shifting ewd and increasing influence in the
upper Ohio Valley by a deep low advancing from the north-central
CONUS.

The stalled frontal zone could potentially be a focus for
isolated to scattered showers again Tue afternoon, mainly along
and south of the Mason-Dixon line, but upper-level support will
be questionable as there remains considerable uncertainty in the
precise ewd progress of the upper low from the nrn Plains. The
most-likely timing will see the boundary begin to retreat nwd
Tue night as low pressure progresses toward the Great Lakes, at
which point chances for showers/storms will increase late Tue
night.

This boundary and the increasing influence of the approaching
upper-level low will focus broad coverage of showers and storms
on Wed, especially to the north of the boundary where warm
advection-driven precipitation is likely. Within the warm
sector, precipitation may be more limited initially, but broad
coverage is likely by Wed afternoon. There is a low probability
of severe weather, but the degree of destabilization is
uncertain owing to potential for early development and broad
coverage of showers and storms.

Rain on Wed night will shift ewd on Thu as the upper trough axis
swings thru the region and out of the forecast area by Thu
evening.

&&

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

- Temperatures return closer to normal by the end of the week
- Potential for overnight temps to be cold enough for frost Sun
  and Mon mornings
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General expectation for the weekend is that broad troughing
lingers in the ern CONUS and highly amplified ridging develops
in the wrn CONUS.

A high degree of uncertainty is evident in ensemble cluster
analysis for the weekend, driven by potential for the wrn ridge
to develop farther ewd than the ensemble mean, and the ern
trough axis to be deeper than the mean, leading to greater
amplitude of the ridge/trough pattern.

This uncertainty could lead to slightly cooler temperature than
the mean might suggest, but regardless will support a trend
toward normal (and even below-normal) temperature late in the
forecast. In fact, the mean minima Sun and Mon mornings
currently shows temp readings in the 30s in many areas, some
below freezing. If the more-amplified pattern comes to pass,
these cold minima could spread farther swd into areas where the
growing season has begun.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure has set up over the area and will continue to
result in VFR conditions through the TAF period. A lack of
gradient in place will make for light and variable winds through
the period as well. Cloud cover will be on the increase as mid
and upper level cloud cover begin to move into the area by the
end of the TAF period. Any shower potential should hold off
until after the TAF period.

.Outlook...
VFR will prevail until restriction potential returns late
Tuesday and Wednesday with approaching low pressure.
Restrictions are possible into Thursday under a subsequent upper
trough.
-- End Changed Discussion --

&&

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

&&

$$

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