Severe Thunderstorm Warning 112, NWS Pittsburgh, PA

Area Forecast Discussion
National Weather Service Pittsburgh PA
1028 AM EDT Thu Jun 22 2017

.SYNOPSIS...
Scattered showers and storms are forecast this afternoon. The
remnants of Cindy make their way into our region tonight into
Saturday. Heavy rain is possible Friday. Dry weather makes a
return late Saturday with cooler weather Sunday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Showers and storms tracking along the Lake Erie shoreline will
continue to be the primary impact today. Latest high resolution
guidance tracks this area across northern sections this
afternoon /during peak heating/. Dry mid levels make damaging
winds the primary hazard. Delta theta-e values around -25 are
below the freezing level so its going to take an icy core to get
well above the 13KFT in order to attain severe levels. Rich low
level moisture will yield downpours with any storm. The cluster
of showers and storms this morning over southwestern PA
produced nearly an inch of rain, illustrating how efficient the
atmosphere is. Temperatures are on track with minimal changes.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
More substantial upper level energy will stream northward from
the lower Ohio Valley tonight. These waves will follow
the intensifying southwest flow aloft, as the remnants of TS
Cindy move over the Lower Mississippi Valley. Deep moisture,
tropical in nature, will also stream northward which will bring
widespread rain and storms to the area late tonight through
Friday night. Warm rain process will develop on Friday,
creating a scenario for very efficient rainfall. As the rain
overspreads the region, a surface cold front will move across
the Upper Midwest, reaching Western Ohio by late in the
afternoon. It is a good bet that rainfall will intensify late
tonight and then ahead of the boundary Friday afternoon, so the
eastward progression of the front will need to be monitored
closely in future model runs. In addition to closely watching
the progression of the front, where the remnants of TS Cindy go,
once it phases in with the upper level flow, will also be
critical.

It will take all of Friday night for the front to exit to the
east, meaning the risk for heavy rain will continue into early
Saturday.

Drier air sags through the area on Saturday behind the exiting
front. This will allow for the area to finally start to dry out
and cool down.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A stark shift in the upper level pattern looks to occur by early
next week. Model and ensemble projections all favor deep
troughing settling over the region by that juncture. With this,
much colder air aloft combined with northwesterly surface flow
will mean temperatures well below normal with chances of showers
as cold air aloft migrates through the region.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
VFR is expected through the period outside of possible scattered
showers/thunderstorms mainly north of KPIT as a stalled frontal
boundary lifts back to the north.

.OUTLOOK...
Widespread restrictions are likely Friday and Friday night with
the encroachment of a cold front.

&&

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

&&

Hazardous Weather Outlook
National Weather Service Pittsburgh PA
418 AM EDT Thu Jun 22 2017

MDZ001-OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>023-
029-031-073>076-WVZ001>004-012-021-509>514-230830-
Garrett-Tuscarawas-Carroll-Columbiana-Coshocton-Harrison-Jefferson-
Muskingum-Guernsey-Belmont-Noble-Monroe-Mercer-Venango-Forest-
Lawrence-Butler-Clarion-Beaver-Allegheny-Armstrong-Indiana-
Washington-Greene-Westmoreland-Westmoreland Ridges-Fayette-
Fayette Ridges-Hancock-Brooke-Ohio-Marshall-Wetzel-Marion-Monongalia-
Ridges of Eastern Monongalia and Northwestern Preston-Preston-
Eastern Preston-Western Tucker-Eastern Tucker-
418 AM EDT Thu Jun 22 2017

This Hazardous Weather Outlook is for western Maryland, east
central Ohio, northwest Pennsylvania, southwest Pennsylvania, west
central Pennsylvania, western Pennsylvania, northern West Virginia
and northern panhandle of West Virginia.

.DAY ONE...Today and Tonight.

Showers and storms will overspread the area late tonight. Storms
could produce locally heavy rainfall and increase the threat for
flooding. A flood watch may be required.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

The threat for heavy rain will continue through Friday. A flood watch
may be required.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
 conditions according to Standard Operating Procedures.