Area Forecast Discussion
Issued by NWS Pittsburgh, PA

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS61 KPBZ 121449

Area Forecast Discussion
National Weather Service Pittsburgh PA
1049 AM EDT Mon Apr 12 2021

Scattered showers today will be followed by dry weather Tuesday
before another crossing low returns shower chances for mid to late


An upper low currently centered over NO OH will result in scattered
showers as it slowly transitions across the forecast area. Coverage
will be greatest during the afternoon as convective temperatures are

Shower coverage will wane tonight as the upper low tracks exits to
the east. Dry weather is then expected Tuesday as shortwave ridging
builds in ahead of another low moving across the Upper Midwest.

Increasing moisture and shortwave support in SW flow ahead of the
next approaching low, and an associated sfc cold front, should
return scattered showers to the region on Wednesday. Scattered
showers should be maintained Wednesday night with the area in close
proximity to the upper low as it deepens across the Lower Great
Lakes. Temperatures should warm to around 5 degrees above average
Tuesday, before returning to more seasonable levels by Wednesday.


Cool weather and scattered showers are expected again
Thursday/Thursday night as the upper low moves east across the Upper
Ohio Valley region. There could be enough cold air aloft for a few
snow showers mixing in, especially across the higher terrain.
Generally dry weather is then expected through early in the weekend
as weak ridging builds in behind the exiting low.

A longwave trough is then progged to set up across much of the
Eastern CONUS late in the weekend through early next week. Shortwaves
moving through the main trough should return shower chances to the
forecast by Sunday.

Continued to side with lower temperature guidance, going below NBM,
through late in the week with cold air aloft associated with the
upper low. Temperatures should gradually return to more seasonable
levels by the weekend.


The passing of an upper level low, ample low level moisture, and
steepening lapse rates will yield MVFR cigs and sct showers through
much of the day. Showers will dissipate this eve as the low shifts
east, with slow w/nw to east cig clearing amid dry air intrusion and
increasing subsidence through Tuesday morning.

Confidence is lower on the timing of Tuesday morning cig clearing,
and interrelated potential for fog development. If clouds clear more
rapidly than forecasted and near sfc moisture remains prominent, more
fog may become more prevalent, favoring FKL/DUJ/ZZV/HLG.

VFR conditions and dry weather is expected by Tuesday aftn.

Another chance for deterioration will be on Wednesday/Thursday with
crossing low pressure.




$$ is the U.S. government's official web portal to all federal, state and local government web resources and services.