Alert archive / Pennsylvania / Flash Flood Warnings in 1999

Flash Flood Warning 53, NWS Pittsburgh, PA

July 28, 1999Allegheny County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 28, 1999, 12:28 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 28, 1999, 12:28 PM EDT (16:28 UTC)
Expired
Jul 28, 1999, 3:00 PM EDT
In force
3 hr
Issued by
NWS Pittsburgh, PA
Area
Whole counties

County Allegheny County, PA

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 4.5 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-pSkew-T log-p diagram, Pittsburgh, PA at 12:00Z on 1999-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1152 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 1999-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 square meters per square second.1939587897Sfc1 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
1152 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
911 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 9:43 AM EDTSevere Thunderstorm WarningPBZLawrence, Mercer58 min
Jul 28, 10:36 AM EDTSevere Thunderstorm WarningPBZLawrence54 min
Jul 28, 10:40 AM EDTFlash Flood WarningPBZMercer2 hr
Jul 28, 10:46 AM EDTFlash Flood WarningPBZLawrence3 hr
Jul 28, 10:47 AM EDTSevere Thunderstorm WarningPBZBeaver58 min
Jul 28, 10:55 AM EDTSevere Thunderstorm WarningPBZButler65 min
Jul 28, 11:30 AM EDTSevere Thunderstorm WarningPBZAllegheny60 min
Jul 28, 11:55 AM EDTSevere Thunderstorm WarningPBZBeaver50 min
Jul 28, 12:17 PM EDTSevere Thunderstorm WarningPBZJefferson58 min
Jul 28, 12:21 PM EDTSevere Thunderstorm WarningPBZWashington54 min
Jul 28, 12:21 PM EDTSevere Thunderstorm WarningPBZFayette54 min
Jul 28, 12:24 PM EDTSevere Thunderstorm WarningPBZAllegheny51 min
Jul 28, 12:27 PM EDTSevere Thunderstorm WarningPBZWestmoreland63 min
Jul 28, 12:34 PM EDTFlash Flood WarningPBZWestmoreland2 hr
Jul 28, 1:03 PM EDTFlash Flood WarningPBZLawrence4 hr
Jul 28, 1:11 PM EDTSevere Thunderstorm WarningPBZFayette64 min
Jul 28, 10:18 AM EDTSevere Thunderstorm WarningPBZCoshocton57 min
Jul 28, 10:44 AM EDTSevere Thunderstorm WarningPBZGuernsey, Tuscarawas61 min
Jul 28, 11:35 AM EDTSevere Thunderstorm WarningPBZCoshocton, Muskingum70 min
Jul 28, 11:44 AM EDTSevere Thunderstorm WarningPBZGuernsey61 min
Jul 28, 11:58 AM EDTSevere Thunderstorm WarningPBZBelmont62 min
Jul 28, 11:59 AM EDTSevere Thunderstorm WarningPBZJefferson61 min
Jul 28, 12:11 PM EDTSevere Thunderstorm WarningPBZMonroe64 min
Jul 28, 12:17 PM EDTSevere Thunderstorm WarningPBZColumbiana58 min
Jul 28, 12:33 PM EDTSevere Thunderstorm WarningPBZTuscarawas42 min
Jul 28, 1:00 PM EDTSevere Thunderstorm WarningPBZCarroll, Harrison45 min
Jul 28, 1:34 PM EDTSevere Thunderstorm WarningPBZMonroe56 min

Nearby

Flash Flood Warnings in Pennsylvania, 1999Every flash flood warning in 1999

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.