189
FXUS61 KPBZ 121324
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
924 AM EDT Wed Mar 12 2025

.SYNOPSIS...
Dry and warm conditions prevail through Friday. Rain returns
this weekend, with the threat of severe weather. A brief
cooldown is favored to begin next week.

&&

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

- Dry weather continues.
- Low RH values with highest wind gusts south of Pittsburgh
  raise some fire weather concern.
-------------------------------------------------------------------

Mid level frontogenesis and 850 mb warm advection is driving a
localized band of clouds this morning draped north of Pittsburgh
in otherwise quiescent conditions. A weak and dry cold front
that passed through the region last evening will slowly lift
northward today as a precip-free warm front. This will make for
a challenging high temperature and dew point forecast today
given ensemble uncertainty in the northward extent of the warm
front exhibited by large spread in HREF wind direction between
Pittsburgh and I-80; this suggests that the front may reach as
far north as I-80 or halt as far south as Pittsburgh metro.
North of the warm front, highs are likely to only reach the
upper 50s while south of it, especially south of I-70, mid to
upper 70s are more likely.

South of the boundary, probability of gusts >20 mph are at 80+%
this afternoon. Moisture advection in southerly flow will
offset mixing into a very dry boundary layer somewhat in the
warm sector, but still large dew point depressions areawide will
allow minRH values to dip into the upper 20% range. Adding to
the importance of the temp and dew point forecast today will be
a fire weather threat south of the warm front where wind gusts
will be highest.

&&

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

- Above average temperatures and continued mainly dry.
- Low chance for showers in the ridges Thursday afternoon.
--------------------------------------------------------------------

There is increasing, but still low confidence in the presence
of a passing shortwave in the mid-level flow tonight into
Thursday, which will push the surface boundary south. The
highest chances of rain will sit mostly in the ridges Thursday
afternoon (20%). Otherwise, conditions will continue to remain
dry with above average temperatures. Marginal fire weather
concerns prevail for the daytime hours.

Forecast confidence increases yet again Friday with the
boundary pushing back northward through the area. It is
beginning to appear that Friday may be the warmest day of the
period with increasing sunshine and temperatures up to 30
degrees above normal.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
KEY MESSAGES:

- Weekend severe weather potential and flooding potential.
- A brief cooldown Monday, with a warmup into mid-week.
-------------------------------------------------------------------

There is increasing confidence in the next disturbance passing
through this weekend. The most likely timing remains, Saturday
for the warm front, with a strong pressure gradient Saturday
afternoon with enhanced low level flow in the warm sector. This
will need to continue to be monitored for severe development,
with ensemble plumes fairly confident on buoyancy, but unsure on
just how much. This might suggest a primary threat of damaging
winds. The main cold front is most likely to pass late Saturday
into early Sunday. Rainfall amounts are quite variable, between
0.5 and 1.5 inches between the 25th and 75th percentile.
Marginal flooding conditions are also possible as the cold front
slowly moves through. Synoptic winds are also forecast at 20 to
30 mph (25th to 75th percentile).

Behind the cold front, a brief cool down to near-normal is
expected with moderate confidence, followed by a warm-up back
above normal by mid-week.

&&

.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
A weak front stalled south of the area will drift back to the
north during the day today. A mix of mid and high clouds will
continue through the period as a result. 850mb frontogenesis
and overrunning will allow for marginally lower clouds north of
the front (FKL/DUJ), but models continue to back off on MVFR so
opted to maintain 5-7kft ceilings instead.

Winds today will vary depending on the position of the front.
Light east-southeast flow is expected at all terminals during
the morning as the front is located south of the area. However,
as the front advances northward this afternoon areas south of
it will see winds veer to southerly or southwesterly and
increase to around 10 kts with occasional gusts to 15-20 kts.
Latest guidance suggests the front makes it as far north as
roughly the I-80 corridor, with winds north of the front
(FKL/DUJ) remaining easterly and generally lighter (7-10 kts).

Outlook...
VFR is favored through early Saturday under the influence
of high pressure with surface wind quickly returning to a
predominant and occasionally gusty SW flow. The return of
restrictions is likely by midday Saturday as a dynamic system brings
rain and the possibility of thunderstorms.

&&

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

&&

$$

SYNOPSIS...22/Milcarek
NEAR TERM...22/MLB
SHORT TERM...22/Milcarek
LONG TERM...Milcarek
AVIATION...Cermak/AK