Alert archive / Pennsylvania / Areal Flood Warnings in 2011
Areal Flood Warning 22, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood warning at Apr 17, 2011, 6:07 AM EDT for Chester 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 outline as issued.
The facts
- Issued
- Apr 17, 2011, 6:07 AM EDT (10:07 UTC)
- Expired
- Apr 17, 2011, 9:00 AM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 109 km from the middle of the area, began a volume at 10:09 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
Washington/Dulle, VA (KIAD), launched 00:00Z, 10.1 hours before the alert went out and 196 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
- 132 J/kg
- Mixed-layer CIN
- -18 J/kg
- Mixed-layer LCL
- 547 m above ground
- 0-6 km bulk shear
- 77 kt
- 0-1 km storm-relative helicity
- 574 m²/s²
- 0-3 km storm-relative helicity
- 593 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.5
The text
As transmitted, in the capitals the NWS used until 2016.
810 WGUS41 KPHI 171007 FLWPHI BULLETIN - IMMEDIATE BROADCAST REQUESTED FLOOD WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 607 AM EDT SUN APR 17 2011 PAC029-171300- /O.NEW.KPHI.FA.W.0022.110417T1007Z-110417T1300Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ CHESTER PA- 607 AM EDT SUN APR 17 2011 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * FLOOD WARNING FOR URBAN AREAS AND SMALL STREAMS IN... NORTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA... * UNTIL 900 AM EDT * RIVERS AND STREAMS CONTINUE TO RUN HIGH FROM SATURDAYS HEAVY RAINS. THE LEVELS WILL CONTINUE TO FALL THIS MORNING. A FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR HAS BEEN REPORTED. STREAM RISES WILL BE SLOW AND FLASH FLOODING IS NOT EXPECTED. HOWEVER...ALL INTERESTED PARTIES SHOULD TAKE NECESSARY PRECAUTIONS IMMEDIATELY. LAT...LON 4023 7566 4007 7543 3995 7571 4004 7590 $$
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 16, 8:08 PM EDT | Areal Flood Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 8 hr |
| Apr 16, 9:11 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 64 min |
| Apr 16, 9:18 PM EDT | River Flood Warning | PHI | Chester | 11 hr |
| Apr 16, 9:32 PM EDT | River Flood Warning | PHI | Delaware | 6 hr |
| Apr 16, 9:49 PM EDT | Special Weather Statement | PHI | Berks, Lehigh | 56 min |
| Apr 16, 11:09 PM EDT | River Flood Warning | PHI | Bucks | 13 hr |
| Apr 16, 11:11 PM EDT | River Flood Warning | PHI | Montgomery | 6 hr |
| Apr 17, 1:05 AM EDT | Areal Flood Warning | PHI | Berks | 5 hr |
| Apr 17, 3:56 AM EDT | Areal Flood Warning | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 6 hr |
| Apr 17, 6:37 AM EDT | River Flood Warning | PHI | Chester, Delaware | 7 hr |
| Apr 17, 9:51 AM EDT | Coastal Flood Warning | PHI | Delaware, Philadelphia | 4 hr |
Nearby
Areal Flood Warnings in Pennsylvania, 2011Every areal flood warning in 2011
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.