Alert archive / Pennsylvania / Flash Flood Warnings in 2021
Flash Flood Warning 2, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 3, 2021, 6:19 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 115 min. 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
- Jun 3, 2021, 6:19 PM EDT (22:19 UTC)
- Expired
- Jun 3, 2021, 8:14 PM EDT
- In force
- 115 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Berks County, PA, Chester County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 22:18 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 |
|---|---|---|---|
| Jun 3, 6:22 PM EDT | FLOOD | 1 Wsw Sanatoga, PA | FLOODING REPORTED ON 422 NEAR POTTSTOWN RESULTING IN A TRAFFIC DISRUPTION. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 10.3 hours before the alert went out and 182 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
- 73 J/kg
- Mixed-layer CIN
- -52 J/kg
- Mixed-layer LCL
- 511 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 116 m²/s²
- 0-3 km storm-relative helicity
- 118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
464
WGUS51 KPHI 032219
FFWPHI
PAC011-029-091-040215-
/O.NEW.KPHI.FF.W.0002.210603T2219Z-210604T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
619 PM EDT Thu Jun 3 2021
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Southeastern Berks County in eastern Pennsylvania...
Chester County in southeastern Pennsylvania...
Southwestern Montgomery County in southeastern Pennsylvania...
* Until 1015 PM EDT.
* At 619 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 2 inches of rain
have fallen. Additional rainfall amounts of 0.5 to 1 inch are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
* Some locations that will experience flash flooding include...
West Chester, Norristown, Pottstown, Phoenixville, West Norriton,
East Norriton, Coatesville, Downingtown, Conshohocken, Ambler,
Birdsboro, and Collegeville.
This includes the following highways...
Pennsylvania Turnpike between mile markers 296 and 337.
Interstate 76 in Pennsylvania between mile markers 327 and 330.
Interstate 176 in Pennsylvania between mile markers 1 and 2.
Interstate 476 in Pennsylvania between mile markers 17 and 19.
Northeast Extension between mile markers 21 and 27.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4018 7594 4036 7560 4014 7519 4006 7535
4007 7536 4004 7541 3982 7589 3985 7602
3985 7601 3987 7600 3987 7599 3993 7600
3993 7598 3995 7599 4004 7593 4011 7594
4014 7587
FLASH FLOOD...RADAR INDICATED
$$
NC1 follow-up statement
941
WGUS71 KPHI 040014
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
814 PM EDT Thu Jun 3 2021
PAC011-029-091-040024-
/O.CAN.KPHI.FF.W.0002.000000T0000Z-210604T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks PA-Chester PA-Montgomery PA-
814 PM EDT Thu Jun 3 2021
...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN BERKS, CHESTER,
AND SOUTHWESTERN MONTGOMERY COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flash Flood Watch remains in effect until 1000 PM EDT for portions
of northern Delaware...southern New Jersey...and southeast
Pennsylvania.
LAT...LON 4018 7594 4036 7560 4014 7519 4006 7535
4007 7536 4004 7541 3982 7589 3985 7602
3985 7601 3987 7600 3987 7599 3993 7600
3993 7598 3995 7599 4004 7593 4011 7594
4014 7587
$$
NCThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 3, 9:37 AM EDT | Flash Flood Watch | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 12 hr |
| Jun 3, 3:02 PM EDT | Special Weather Statement | PHI | Berks | 43 min |
| Jun 3, 3:54 PM EDT | Special Weather Statement | PHI | Berks | 36 min |
| Jun 3, 5:14 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester | 27 min |
| Jun 3, 5:20 PM EDT | Areal Flood Advisory | PHI | Berks, Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Jun 3, 5:59 PM EDT | Flash Flood Warning | PHI | Berks, Chester | 108 min |
| Jun 3, 7:09 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 2 hr |
| Jun 3, 7:13 PM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery, Philadelphia | 3 hr |
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.