179
FXUS61 KPBZ 090529
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1229 AM EST Sun Nov 9 2025

.SYNOPSIS...
There is the potential for fog early Sunday south of Pittsburgh.
Rain chances increase after dawn with a passing low pressure
disturbance. Rain showers will transition to snow showers after
dark Sunday with advancing cold air. Snow accumulations could
impact the higher terrain and areas north of I-80 Monday into
Tuesday.

&&

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

- Potential for fog early Sunday south of Pittsburgh
- Rain chances increase after dawn Sunday
- Rain is expected to change to snow between 7pm to 11pm Sunday
---------------------------------------------------------------

Quiet and dry conditions are anticipated from late this evening
until 2am, under the influence of high pressure. There`s a
possibility of clearing skies south of Pittsburgh, which could
lead to fog formation.

A low-pressure system currently over Illinois will move into our
area after sunrise on Sunday. Due to warm temperatures as winds
remain from the east/southeast and/or variable, the
precipitation will begin as rain. Expect light rainfall, ranging
from a trace a tenth of an inch to a quarter of inch through
7pm.

From 7pm to 11pm, rain showers are expected to briefly change to
a wintry mix before turning into snow. As the low-pressure
system moves northeast into New York, north/northwest winds will
likely bring lake-effect snow due to warm lake temperatures.
Higher elevations in the Laurel Highlands and West Virginia
might see light snow accumulation before midnight as well due to
upsloping.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
KEY MESSAGES:

- Snow shower expected Sunday night into Monday
- Travel impacts could occur in areas under a lake-effect snow
  band
----------------------------------------------------------------

Falling temperatures and ongoing snow showers are expected
Sunday night into early Monday morning. With warm ground
temperatures and prior to the system moving through, only a few
tenths of an inch (mainly on grass and elevated surfaces) are
expected by sunrise on Monday.

The upper-level trough will continue to move across the region on
Monday. Differences remain in the upper patterns between the GEFS
and the Euro with the duration of the NW flow. Differences in the
flow would result in differing snow accumulations through Tuesday.
Despite these differences, the picture remains the same that NW flow
will bring scattered to numerous snow showers across portions of the
OH Valley.

850mb temperatures are expected to drop to between -8 to -10 deg C
by Monday, while Lake Erie temperatures hover around +12 to +14 deg
C. Lake and terrain enhancement will be likely Monday night into
Tuesday before flow backs to the W and the most efficient lake and
terrain enhancement is turned north of the region. Mesoscale
features (such as a reinforcing surface trough) will greatly affect
SFC to 850mb flow and thus the positioning, duration, and intensity
of any heavier focused lake bands remains low confidence at this
time. Despite this, models continue to hint at the likelihood of one
or several lake bands yielding enhanced snowfall near and south of
Lake Erie. NBM probabilities for advisory level snowfall continue to
fluctuate. Currently, there is a 40%-60% north of I-80 while
the PA and WV ridges probabilities remain between 30%-40%. We
will continue to monitor the evolution of this system and
pattern over the coming forecast periods.

&&

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

- Cold temperatures and snow showers continue Tuesday
- Unsettled Wednesday and Thursday with occasional rain/snow
  chances mainly north of Pittsburgh
- Apparent temperatures in the teens Tuesday morning
-------------------------------------------------------------------

The surface trough is will shift to the northeast of the area on
Tuesday, as boundary layer flow backs to the SW and snow chances
decrease through the day. Broad upper troughing is then expected to
persist across areas from the Upper Midwest into New England.
Occasional rain/snow chances will be possible, mainly north of PIT,
as individual shortwaves rotate through the trough.

Temperatures are expected to be 15 to 20 degrees below average
Monday and Tuesday, before moderating some by mid week.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Patchy MVFR fog is expected early this morning, though
increasing mid and high level clouds ahead of approaching low
pressure should keep coverage minimal, especially as clouds
thicken and lower toward daybreak.

Otherwise, low pressure will track across OH and western PA
later this morning into the afternoon, with showers and MVFR
restrictions expected. The low will pull a cold front across the
areas as it tracks NEWD. A decrease in shower activity is
expected initially after FROPA, along with a WSHFT to the W-WSW.
Continued MVFR cigs are expected to continue through late
afternoon in cold advection behind the front.

Additional showers, and IFR restrictions, are expected this
evening as a deepening upper level low approaches the region.
Critical thicknesses and model soundings indicate a changeover
to snow showers is likely by late evening into the overnight
hours in cold advection, as IFR continues.

Outlook...
IFR should continue into Monday morning with snow showers, with
some improvement to MVFR for most locations by afternoon as
mixing lifts cig heights. By late afternoon, lake enhancement
could result in localized IFR conditions in narrow snow bands,
especially across wrn PA.

These conditions are expected to continue into Tuesday before
the upper low tracks NE of the area, and wind backs to the SW
ending the lake enhancement. Patchy restrictions in snow are
possible again Tuesday night in warm advection, before high
pressure returns VFR for Thursday.

&&

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

&&

$$

SYNOPSIS...Hefferan
NEAR TERM...Hefferan
SHORT TERM...Hefferan
LONG TERM...Lupo/AK
AVIATION...WM