Alert archive / Pennsylvania / Flash Flood Warnings in 2019

Flash Flood Warning 102, NWS Pittsburgh, PA

August 18, 2019Mercer County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Aug 18, 2019, 6:10 PM EDT for Mercer County, Pennsylvania. It was in force for 90 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 18, 2019, 6:10 PM EDT (22:10 UTC)
Expired
Aug 18, 2019, 7:40 PM EDT
In force
90 min
Issued by
NWS Pittsburgh, PA
Area
Storm-based polygon
Flood severity
None

County Mercer County, PA

The radar

The Pittsburgh radar (KPBZ), 86 km from the middle of the area, began a volume at 22:11 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, 10.2 hours before the alert went out and 100 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-pSkew-T log-p diagram, Pittsburgh, PA at 12:00Z on 2019-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 566 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Pittsburgh, PA at 12:00Z on 2019-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
566 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1315 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
113 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7

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 Aug 18, 5:16 PM EDT, 54 minutes earlier.

Area forecast discussion, Aug 18, 5:16 PM EDT, 54 minutes before
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Hazardous weather outlook, Aug 18, 4:04 AM EDT, 14 hours 6 minutes before
Hazardous Weather Outlook
National Weather Service Pittsburgh PA
404 AM EDT Sun Aug 18 2019

MDZ001-OHZ059-068-069-PAZ031-074>076-WVZ004-012-021-509>514-190815-
Garrett-Belmont-Noble-Monroe-Greene-Westmoreland Ridges-Fayette-
Fayette Ridges-Marshall-Wetzel-Marion-Monongalia-
Ridges of Eastern Monongalia and Northwestern Preston-Preston-
Eastern Preston-Western Tucker-Eastern Tucker-
404 AM EDT Sun Aug 18 2019

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

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

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

OHZ039>041-048>050-057-058-PAZ007>009-013>016-020>023-029-073-
WVZ001>003-190815-
Tuscarawas-Carroll-Columbiana-Coshocton-Harrison-Jefferson OH-
Muskingum-Guernsey-Mercer-Venango-Forest-Lawrence-Butler-Clarion-
Jefferson PA-Beaver-Allegheny-Armstrong-Indiana-Washington-
Westmoreland-Hancock-Brooke-Ohio-
404 AM EDT Sun Aug 18 2019

This Hazardous Weather Outlook is for 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.

Isolated severe storms are possible this afternoon and evening.
Damaging wind gusts or a moisture laden downburst is possible.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Local storm report, Aug 18, 4:33 PM EDT, 1 hour 37 minutes before
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Special weather statement, Aug 18, 4:58 PM EDT, 1 hour 12 minutes before
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Special weather statement, Aug 18, 5:09 PM EDT, 1 hour 1 minute before
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Special weather statement, Aug 18, 5:26 PM EDT, 44 minutes before
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Special weather statement, Aug 18, 5:34 PM EDT, 36 minutes before
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Local storm report, Aug 18, 5:39 PM EDT, 31 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 8:34 AM EDTSpecial Weather StatementPBZVenango26 min
Aug 18, 12:35 PM EDTSevere Thunderstorm WarningPBZArmstrong, Clarion, Jefferson27 min
Aug 18, 1:05 PM EDTSpecial Weather StatementPBZJefferson40 min
Aug 18, 1:19 PM EDTSpecial Weather StatementPBZWashington41 min
Aug 18, 2:02 PM EDTSevere Thunderstorm WarningPBZAllegheny, Fayette, Washington, Westmoreland43 min
Aug 18, 2:08 PM EDTSpecial Weather StatementPBZClarion37 min
Aug 18, 2:13 PM EDTSevere Thunderstorm WarningPBZArmstrong, Clarion, Jefferson47 min
Aug 18, 2:17 PM EDTSevere Thunderstorm WarningPBZFayette, Westmoreland43 min
Aug 18, 2:21 PM EDTSevere Thunderstorm WarningPBZWashington39 min
Aug 18, 2:26 PM EDTSevere Thunderstorm WarningPBZWestmoreland49 min
Aug 18, 2:48 PM EDTSevere Thunderstorm WarningPBZIndiana, Jefferson28 min
Aug 18, 2:50 PM EDTSevere Thunderstorm WarningPBZIndiana, Westmoreland28 min
Aug 18, 2:52 PM EDTSpecial Weather StatementPBZFayette23 min
Aug 18, 3:00 PM EDTSevere Thunderstorm WarningPBZFayette, Greene45 min
Aug 18, 3:23 PM EDTSpecial Weather StatementPBZFayette37 min
Aug 18, 3:29 PM EDTSpecial Weather StatementPBZFayette31 min
Aug 18, 3:33 PM EDTSpecial Weather StatementPBZIndiana27 min
Aug 18, 3:35 PM EDTSevere Thunderstorm WarningPBZIndiana, Jefferson13 min
Aug 18, 3:38 PM EDTSevere Thunderstorm WarningPBZFayette, Washington, Westmoreland18 min
Aug 18, 4:21 PM EDTSpecial Weather StatementPBZAllegheny24 min
Aug 18, 4:58 PM EDTSpecial Weather StatementPBZMercer32 min
Aug 18, 5:26 PM EDTSpecial Weather StatementPBZClarion, Forest19 min
Aug 18, 5:30 PM EDTSevere Thunderstorm WarningPBZClarion, Forest, Jefferson, Venango45 min
Aug 18, 5:34 PM EDTSpecial Weather StatementPBZMercer26 min
Aug 18, 5:38 PM EDTSevere Thunderstorm WarningPBZMercer52 min
Aug 18, 5:47 PM EDTAreal Flood AdvisoryPBZMercer3 hr
Aug 18, 6:11 PM EDTSevere Thunderstorm WarningPBZClarion, Forest, Jefferson34 min
Aug 18, 6:22 PM EDTSpecial Weather StatementPBZForest, Venango23 min
Aug 18, 7:06 PM EDTSpecial Weather StatementPBZForest24 min
Aug 18, 7:27 PM EDTSpecial Weather StatementPBZMercer33 min
Aug 18, 7:29 PM EDTSpecial Weather StatementPBZClarion31 min
Aug 18, 7:55 PM EDTSpecial Weather StatementPBZMercer35 min
Aug 18, 2:34 PM EDTSpecial Weather StatementPBZNoble26 min
Aug 18, 5:09 PM EDTSpecial Weather StatementPBZTucker21 min

Nearby

Flash Flood Warnings in Pennsylvania, 2019Every 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.