Alert archive / Pennsylvania / Flash Flood Warnings in 2019

Flash Flood Warning 48, NWS Pittsburgh, PA

July 4, 2019Allegheny County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 4, 2019, 5:56 PM EDT for Allegheny County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 4, 2019, 5:56 PM EDT (21:56 UTC)
Expired: Jul 4, 2019, 9:00 PM EDT
In force: 3 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

County Allegheny County, PA

The radar

The Pittsburgh radar (KPBZ), 21 km from the middle of the area, began a volume at 21:56 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 9.9 hours before the alert went out and 12 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 287 J/kg
Mixed-layer CIN: -62 J/kg
Mixed-layer LCL: 1002 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 30 m²/s²
0-3 km storm-relative helicity: 40 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Pittsburgh, PA wrote its last area forecast discussion before this flash flood warning went out at Jul 4, 3:50 PM EDT, 2 hours 6 minutes earlier.

Area forecast discussion, Jul 4, 3:50 PM EDT, 2 hours 6 minutes before

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Hazardous weather outlook, Jul 4, 5:34 PM EDT, 22 minutes before

Hazardous Weather Outlook
National Weather Service Pittsburgh PA
534 PM EDT Thu Jul 4 2019

MDZ001-OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>023-
029-031-073>076-WVZ001>004-012-021-509>514-052145-
Garrett-Tuscarawas-Carroll-Columbiana-Coshocton-Harrison-
Jefferson OH-Muskingum-Guernsey-Belmont-Noble-Monroe-Mercer-Venango-
Forest-Lawrence-Butler-Clarion-Jefferson PA-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-
534 PM EDT Thu Jul 4 2019

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...Tonight.

Hazardous weather is not expected at this time.

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

Localized flash flooding is possible through Saturday with
thunderstorms, mainly during the afternoon and evening hours.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, Jul 4, 1:03 PM EDT, 4 hours 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
103 PM EDT THU JUL 04 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1259 PM     FLASH FLOOD      2 SE ASHER GLADE        39.69N  79.42W
07/04/2019                   GARRETT            MD   FIRE DEPT/RESCUE

            HIGH WATER ON BUFFALO RUN RD.

&&

EVENT NUMBER PBZ1902539

JD

Local storm report, Jul 4, 2:13 PM EDT, 3 hours 43 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
213 PM EDT THU JUL 04 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0209 PM     FLASH FLOOD      3 E KREGAR              40.13N  79.25W
07/04/2019                   WESTMORELAND       PA   DEPT OF HIGHWAYS

            LANDSLIDE DUE TO HEAVY RAIN ACROSS THE AREA.

&&

EVENT NUMBER PBZ1902540

JD

Local storm report, Jul 4, 2:22 PM EDT, 3 hours 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
222 PM EDT THU JUL 04 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0215 PM     FLASH FLOOD      2 SSE PLEASANT GROVE    40.16N  79.27W
07/04/2019                   WESTMORELAND       PA   DEPT OF HIGHWAYS

            WHITE OAK RUN IS OUT OF THE BANK AND AFFECTING WEAVER
            ROAD

&&

EVENT NUMBER PBZ1902541

JD

Local storm report, Jul 4, 3:18 PM EDT, 2 hours 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
318 PM EDT THU JUL 04 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0200 PM     FLASH FLOOD      FRIENDSVILLE            39.66N  79.41W
07/04/2019                   GARRETT            MD   911 CALL CENTER

            ROAD CLOSED

&&

EVENT NUMBER PBZ1902542

07

The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 4, 11:18 AM EDT	Flash Flood Watch	PBZ	Fayette, Westmoreland	6 hr
Jul 4, 11:53 AM EDT	Flash Flood Warning	PBZ	Westmoreland	4 hr
Jul 4, 4:49 PM EDT	Areal Flood Warning	PBZ	Westmoreland	3 hr
Jul 4, 6:59 PM EDT	Flash Flood Warning	PBZ	Allegheny	2 hr
Jul 4, 7:21 PM EDT	Flash Flood Warning	PBZ	Armstrong, Butler, Clarion, Venango	3 hr
Jul 4, 1:49 PM EDT	Flash Flood Warning	PBZ	Tucker	3 hr
Jul 4, 2:32 PM EDT	Flash Flood Warning	PBZ	Preston, Tucker	3 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2019 Every flash flood warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.