666
FXUS61 KPBZ 171520
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1020 AM EST Mon Nov 17 2025

.SYNOPSIS...
Lake-effect snow showers will taper off before 1pm. A passing
system early Tuesday may produce a brief period of wintry mix or
snow before transitioning to rain in the afternoon and evening.
Milder conditions are expected toward the end of the week.

&&

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

- Lake-effect snow showers through 1pm
- Quiet and dry conditions late this evening

----------------------------------------------------------------

With the snow band shifting into northwest Pennsylvania, Clarion
and Venango Counties have been removed from the Winter Weather
Advisory. Any additional accumulation this afternoon should be
light and is not expected to impact travel. For Jefferson and
Forest County, lake-effect snow bands continue to stream into
the area, and headlines remain in effect for an additional 1 to
2 inches of snow.

Boundary layer winds back slightly by early this afternoon
causing weakening and a northward shift in the heavy snow band,
ending the threat for significant snowfall.

Clear and quiet conditions are expected this afternoon and into
late evening as a ridge builds in from the west. Temperatures
will run about 5 degrees below normal today, with persistent
northwest flow maintaining colder air across the region.

&&

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

- Dry and quiet Monday night
- Another system crosses the region Tuesday returning a
  rain/snow mix
- Possibly slick commutes Tuesday and Wednesday mornings
----------------------------------------------------------------

Subtle high pressure noses down through the Ohio Valley from
the Upper Midwest by Monday night. This helps to promote quiet
and dry conditions as well as slacken the SFC pressure gradient
finally ending breezy conditions across the region. Clear and
calm conditions promote efficient radiative cooling overnight
and low temperatures Tuesday morning will likely trend between
5-10 degrees below average.

After sunrise on Tuesday, a new quick hitting system moves out
of the northern Plains and crosses the Ohio Valley returning
precipitation chances. At onset, precipitation could begin as
snow, with lingering low-level dry air supporting some wet
bulbing aloft. Forecast soundings look to even support some
amount of sleet with a minimal warm nose above a SFC layer just
below or at freezing. Temperature profiles hover near freezing
through the low levels and support a heavy, wet snow with
limited accumulations. Some amount of caution is advised for the
Tuesday morning commute with frozen precipitation falling and
SFC temps below freezing.

Precipitation mixes with then turns over to all rain by late
morning or early afternoon amid warming SFC temps and ongoing
WAA. Rainfall amounts are expected to be on the lighter side in
the lowlands, generally between 0.10-0.25 inches. Higher
amounts, perhaps closer to 0.50-1.00 inches look to be possible
in the WV ridges owing to more prolonged upsloping. POPs begin
to wane by late Tuesday night but some model soundings hint at
the low end possibility for precipitation to end as isolated
instances of ice across our eastern ridges. As such, there could
be slick spots to watch out for on the Wednesday morning
commute, mainly in the eastern ridges.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
KEY MESSAGES:

- Above average temperatures into next weekend
- Rain chances rise again late week with another passing
  disturbance likely
-------------------------------------------------------------------

Ensembles continue to prog height rises during the latter half
of the week supporting moderating temperatures. Despite ridge
building aloft, inverted troughing across the Ohio Valley may
support low end rain chances Wednesday night and Thursday.

A majority of clustered ensembles continue to favor a shortwave
trough dropping from the Canadian Prairies into the Great Lakes
by Thursday night. There continue to be large differences in
both strength and timing of this wave. However, increasingly
moist southwest flow spurs increasing rain chances by as early
as Thursday night with an advancing warm front. The associated
cold FROPA looks to occur Friday/Friday night triggering a
northwest flow regime that could keep POPs elevated through
Saturday. A drier trend may return by Sunday as ensembles weakly
agree on subtle height rises. However, a largely "zonal" flow
look to ensembles by late this weekend or early next week may be
more indicative of smoothing out subtle differences in each
member rather than an actual zonal flow regime.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
Lake effect snow showers will continue north of I-80 this
morning. Most ports are expected to remain VFR, but KDUJ may see
periods of MVFR restrictions with snow within a linger snow
band.

With a tight pressure gradient, expected wind gusts to range
between 25 to 35 kts today.

Restrictions are expected to increase early tomorrow morning
between 12Z and 16Z as a low-pressure system approaches the Ohio
River Valley from the west. Lingering mid and low-level dry air
may allow precipitation to begin as snow or as a wintry mix as
moisture moves into eastern Ohio. Conditions will largely depend
on the speed of the low`s progression into the Midwest and the
onset time of the warm advection. A faster arrival time would
favor a period (1-2 hrs) of snow or sleet before changing to
rain at some terminals. If the low remains farther west for
longer, the likelihood of a wintry mix or snow will be reduced.

Cigs will likely fall to MVFR followed by IFR after 15Z Tuesday
with increasing boundary layer saturation and remain low into
into early Wednesday.

Outlook...

Periodic restriction and precipitation chances are expected
through next weekend as the area remains under a relatively
active weather pattern.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Lake Effect Snow Warning until 1 PM EST this afternoon for
     PAZ009.
     Winter Weather Advisory until 1 PM EST this afternoon for
     PAZ016.
OH...None.
WV...None.

&&

$$

SYNOPSIS...Hefferan
NEAR TERM...Hefferan
SHORT TERM...AK
LONG TERM...AK
AVIATION...Hefferan