Alert archive / Pennsylvania / Areal Flood Warnings in 2009
Areal Flood Warning 13, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 2, 2009, 1:25 PM EDT for Montgomery County, Philadelphia County, Pennsylvania. It was in force for 6 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
- Aug 2, 2009, 1:25 PM EDT (17:25 UTC)
- Expired
- Aug 2, 2009, 7:15 PM EDT
- In force
- 6 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Montgomery County, PA, Philadelphia County, PA
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 5.4 hours before the alert went out and 215 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
- 105 J/kg
- Mixed-layer CIN
- -79 J/kg
- Mixed-layer LCL
- 723 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 73 m²/s²
- 0-3 km storm-relative helicity
- 111 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted, in the capitals the NWS used until 2016.
000 WGUS41 KPHI 021725 FLWPHI BULLETIN - IMMEDIATE BROADCAST REQUESTED FLOOD WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 125 PM EDT SUN AUG 2 2009 PAC091-101-022315- /O.NEW.KPHI.FA.W.0013.090802T1725Z-090802T2315Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ PHILADELPHIA PA-MONTGOMERY PA- 125 PM EDT SUN AUG 2 2009 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * FLOOD WARNING FOR URBAN AREAS AND SMALL STREAMS IN... SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA... WESTERN PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA... * UNTIL 715 PM EDT * UP TO 2 INCHES OF RAIN HAS CAUSED THE WISSAHICKON CREEK AND OTHER SMALL STREAMS AND CREEKS IN THE AREA TO FLOOD. URBAN FLOODING HAS ALSO BEEN REPORTED. THE HEAVY RAIN HAS MOVED OUT OF THE AREA BUT A FEW ADDITIONAL SHOWERS ARE POSSIBLE INTO THE EVENING HOURS. WATER LEVELS WILL BEGIN TO LOWER LATER THIS AFTERNOON. 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. PRECAUTIONARY/PREPAREDNESS ACTIONS... DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. MOVE TO HIGHER GROUND. && LAT...LON 4020 7521 4018 7510 3991 7520 3998 7528 $$ RPW
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 2:19 AM EDT | Flash Flood Watch | PHI | Berks, Carbon, Delaware, Lehigh, Monroe, Northampton and 1 more | 13 hr |
| Aug 2, 3:29 AM EDT | Areal Flood Advisory | PHI | Berks | 3 hr |
| Aug 2, 5:54 AM EDT | Areal Flood Advisory | PHI | Chester | 3 hr |
| Aug 2, 7:34 AM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery, Philadelphia | 3 hr |
| Aug 2, 7:51 AM EDT | Areal Flood Warning | PHI | Chester | 4 hr |
| Aug 2, 9:04 AM EDT | Areal Flood Warning | PHI | Montgomery, Philadelphia | 4 hr |
| Aug 2, 9:06 AM EDT | Flash Flood Warning | PHI | Berks, Carbon, Chester, Lehigh, Monroe, Northampton | 4 hr |
| Aug 2, 10:08 AM EDT | Flash Flood Warning | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 9 hr |
| Aug 2, 10:08 AM EDT | Severe Thunderstorm Warning | PHI | Chester | 67 min |
| Aug 2, 10:24 AM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery | 66 min |
| Aug 2, 10:53 AM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 67 min |
| Aug 2, 11:14 AM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Montgomery, Northampton | 61 min |
| Aug 2, 11:25 AM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery, Philadelphia | 65 min |
| Aug 2, 11:48 AM EDT | Severe Thunderstorm Warning | PHI | Bucks | 57 min |
| Aug 2, 11:51 AM EDT | Tornado Warning | PHI | Bucks | 24 min |
| Aug 2, 12:33 PM EDT | River Flood Warning | PHI | Bucks | 28 hr |
| Aug 2, 4:06 PM EDT | Areal Flood Advisory | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 4 hr |
| Aug 2, 4:21 PM EDT | River Flood Warning | PHI | Chester | 56 min |
| Aug 2, 4:22 PM EDT | Flash Flood Warning | PHI | Berks | 2 hr |
| Aug 2, 6:15 PM EDT | Areal Flood Warning | PHI | Montgomery, Philadelphia | 4 hr |
| Aug 2, 6:25 PM EDT | Areal Flood Warning | PHI | Philadelphia | 4 hr |
Nearby
Areal Flood Warnings in Pennsylvania, 2009Every areal flood warning in 2009
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.