Alert archive / Pennsylvania / Flash Flood Warnings in 2021
Flash Flood Warning 15, NWS Pittsburgh, PA
NWS Pittsburgh, PA issued this flash flood warning at Jul 17, 2021, 12:34 PM EDT for Mercer County, Venango County, Pennsylvania. It was in force for 3 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 17, 2021, 12:34 PM EDT (16:34 UTC)
- Expired
- Jul 17, 2021, 3:45 PM EDT
- In force
- 3 hr
- Issued by
- NWS Pittsburgh, PA
- Area
- Storm-based polygon
- Flood severity
- None
Counties Mercer County, PA, Venango County, PA
The radar
The Pittsburgh radar (KPBZ), 109 km from the middle of the area, began a volume at 16:34 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 17, 1:15 PM EDT | FLASH FLOOD | 1 Nnw Dempseytown, PA | PUMP STATION ROAD IS IMPASSIBLE DUE TO WATER OVER THE ROAD. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Pittsburgh, PA (KPIT), launched 12:00Z, 4.6 hours before the alert went out and 121 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.
- Mixed-layer CAPE
- 70 J/kg
- Mixed-layer CIN
- -81 J/kg
- Mixed-layer LCL
- 882 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 80 m²/s²
- 0-3 km storm-relative helicity
- 128 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.2
The text
As transmitted.
182
WGUS51 KPBZ 171634
FFWPBZ
PAC085-121-171945-
/O.NEW.KPBZ.FF.W.0015.210717T1634Z-210717T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
1234 PM EDT Sat Jul 17 2021
The National Weather Service in Pittsburgh has issued a
* Flash Flood Warning for...
Northern Mercer County in northwestern Pennsylvania...
Northwestern Venango County in northwestern Pennsylvania...
* Until 345 PM EDT.
* At 1234 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 1.5 inches of
rain have fallen on saturated ground. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Hermitage, Sharon, Sharpsville, Greenville, Sugarcreek, Farrell,
Stoneboro, Sandy Lake, Clark, Wheatland, Fredonia, Cooperstown,
Utica, New Lebanon, Sheakleyville, Maurice K Goddard State Park
and Oil Creek State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 4120 8050 4140 8050 4148 8029 4149 8000
4151 7998 4153 7994 4154 7994 4154 7992
4155 7993 4155 7991 4157 7989 4157 7987
4160 7983 4162 7983 4162 7973 4152 7963
FLASH FLOOD...RADAR INDICATED
$$1 follow-up statement
926
WGUS71 KPBZ 171747
FFSPBZ
Flash Flood Statement
National Weather Service Pittsburgh PA
147 PM EDT Sat Jul 17 2021
PAC085-121-171945-
/O.CON.KPBZ.FF.W.0015.000000T0000Z-210717T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer PA-Venango PA-
147 PM EDT Sat Jul 17 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 PM EDT THIS
AFTERNOON FOR NORTHERN MERCER AND NORTHWESTERN VENANGO COUNTIES...
At 147 PM EDT, Doppler radar indicated showers producing light to
moderate rain across the warned area. Between 1.5 and 2 inches of
rain have fallen on saturated ground over the past 6 hours. Flash
flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Hermitage, Sharon, Sharpsville, Greenville, Sugarcreek, Farrell,
Stoneboro, Sandy Lake, Clark, Wheatland, Fredonia, Cooperstown,
Utica, New Lebanon, Sheakleyville, Maurice K Goddard State Park
and Oil Creek State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 4120 8050 4140 8050 4148 8029 4149 8000
4151 7998 4153 7994 4154 7994 4154 7992
4155 7993 4155 7991 4157 7989 4157 7987
4160 7983 4162 7983 4162 7973 4152 7963
FLASH FLOOD...RADAR INDICATED
$$The office that day
Everything else NWS Pittsburgh, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 16, 10:28 PM EDT | Areal Flood Advisory | PBZ | Mercer, Venango | 3 hr |
| Jul 17, 2:46 AM EDT | Flash Flood Watch | PBZ | Armstrong, Beaver, Butler, Clarion, Forest, Jefferson and 3 more | 15 hr |
| Jul 17, 11:21 AM EDT | Areal Flood Advisory | PBZ | Forest, Mercer, Venango | 4 hr |
| Jul 17, 1:39 PM EDT | Areal Flood Advisory | PBZ | Allegheny, Washington | 3 hr |
| Jul 17, 2:30 PM EDT | Severe Thunderstorm Warning | PBZ | Armstrong, Indiana, Westmoreland | 45 min |
| Jul 17, 2:51 PM EDT | Severe Thunderstorm Warning | PBZ | Indiana | 39 min |
| Jul 17, 4:01 PM EDT | Areal Flood Advisory | PBZ | Allegheny, Fayette, Greene, Washington, Westmoreland | 92 min |
| Jul 17, 4:30 PM EDT | Severe Thunderstorm Warning | PBZ | Fayette, Westmoreland | 45 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2021Every flash flood warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.