Alert archive / Pennsylvania / Flash Flood Warnings in 2009
Flash Flood Warning 9, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 13, 2009, 2:57 PM EDT for Montgomery County, Pennsylvania. It was in force for 2 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
- Jun 13, 2009, 2:57 PM EDT (18:57 UTC)
- Expired
- Jun 13, 2009, 5:00 PM EDT
- In force
- 2 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 66 km from the middle of the area, began a volume at 19:00 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 12:00Z, 7.0 hours before the alert went out and 234 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
- 18 J/kg
- Mixed-layer CIN
- -76 J/kg
- Mixed-layer LCL
- 989 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- -30 m²/s²
- 0-3 km storm-relative helicity
- 38 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
WGUS51 KPHI 131857
FFWPHI
PAC091-132100-
/O.NEW.KPHI.FF.W.0009.090613T1857Z-090613T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
257 PM EDT SAT JUN 13 2009
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* FLASH FLOOD WARNING FOR...
EAST CENTRAL MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
THIS INCLUDES THE CITY OF WILLOW GROVE...
* UNTIL 500 PM EDT
* AT 253 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA IN AND
AROUND PARK CREEK. THUNDERSTORMS ARE NEARLY STATIONARY OVER THE
AREA.
* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SPRING
HOUSE AND HORSHAM.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.
&&
LAT...LON 4007 7513 4017 7529 4025 7522 4016 7506
4014 7504
$$
GIGIThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 13, 2:27 PM EDT | Areal Flood Advisory | PHI | Chester | 4 hr |
| Jun 13, 2:32 PM EDT | Flash Flood Warning | PHI | Bucks | 2 hr |
| Jun 13, 2:33 PM EDT | Flash Flood Warning | PHI | Carbon, Lehigh, Monroe, Northampton | 112 min |
| Jun 13, 3:17 PM EDT | Areal Flood Advisory | PHI | Bucks | 3 hr |
| Jun 13, 4:07 PM EDT | Flash Flood Warning | PHI | Bucks, Montgomery, Philadelphia | 6 hr |
| Jun 13, 4:59 PM EDT | Areal Flood Advisory | PHI | Chester | 4 hr |
| Jun 13, 5:16 PM EDT | River Flood Warning | PHI | Bucks | 13 hr |
| Jun 13, 6:06 PM EDT | Flash Flood Warning | PHI | Chester | 2 hr |
| Jun 13, 6:39 PM EDT | Severe Thunderstorm Warning | PHI | Monroe | 66 min |
| Jun 13, 7:29 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 61 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2009Every flash 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; radar from the NEXRAD Level II archive.