Area Forecast Discussion
Issued by NWS

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 291319

Area Forecast Discussion
National Weather Service Pittsburgh PA
919 AM EDT Fri May 29 2020

Strong to severe storms will develop out ahead of an approaching cold
front this afternoon with the daytime max heating. Expect the
strongest storms to arrive later this evening with the cold front.


As the surface temperatures rise this morning, surface based
instability will be on the increase as prefrontal showers and even a
few thunderstorms begin to develop into OH. By noon, surface
temperatures reaching the mid and upper 70s and dew points in the mid
60s will create a favorable environment with 1500 to 1800 J/KG CAPE
values developing. With this trend, will expect to see stronger storm
development by 18Z. Lapse rates are pretty marginal this morning but
will see some slightly steeper rates after 16Z.

Tonight, will begin to see the front push through the area by 00Z.
With this forcing, showers and thunderstorms will persist through the
rest of the night. The stronger storms will more than likely
coincide with the daytime heating before 00Z. Assist from the front
pushing through will keep some stronger storms going through the
overnight period.


With low-level residual moisture and prevailing NW flow (i.e. cold
advection) expected early Saturday morning, a low stratus deck/some fog
will form before sunrise across the region.

A weak shortwave advancing across Lake Erie may produce scattered
rain showers briefly Saturday afternoon. High pressure building over
the Great Lakes will return quiet, dry weather Saturday evening.


An elongated upper-level trough will continue to stay over the Great
Lakes Saturday night through Monday and bring abnormally cold air to
the region. Max temps will roughly stay 10 degrees below normal on
Sunday and Monday morning.

Temperatures will return to the climatological average Tuesday under
warm, moist advection.

The next chance for precip will arrive on Wednesday with a strong
shortwave riding over the ridge into the forecast area. This will
keep unsettled weather over the area from Wed through Thursday next


Although a couple of terminals may see brief MVFR/IFR ceilings
through mid-morning, mainly VFR conditions are expected through
midday. Showers and thunderstorms are expected to develop after 17Z
ahead of an an approaching shortwave and cold front. Initial activity
will be scattered, but more organized activity is expected during the
late afternoon/evening hours, generally between 18Z and 00Z. Handled
with VCTS for now. Any storm will be capable of strong wind gusts of
40-50 knots and some hail.

Activity will cease with FROPA tonight. Lingering low-level moisture
and cold advection may lead to restrictive stratus/fog overnight.

High pressure will result in VFR this weekend outside of patchy early
morning fog.




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