Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 211, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 21, 2009, 12:20 PM EDT for Berks County, Pennsylvania. It was in force for 55 min. 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 21, 2009, 12:20 PM EDT (16:20 UTC)
- Expired
- Aug 21, 2009, 1:15 PM EDT
- In force
- 55 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Berks County, PA
The radar
The Philadelphia radar (KDIX), 160 km from the middle of the area, began a volume at 16:22 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 21, 11:28 AM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 4.3 hours before the alert went out and 115 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
- 96 J/kg
- Mixed-layer CIN
- -66 J/kg
- Mixed-layer LCL
- 930 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 43 m²/s²
- 0-3 km storm-relative helicity
- 108 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 211620
SVRPHI
PAC011-211715-
/O.NEW.KPHI.SV.W.0211.090821T1620Z-090821T1715Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1220 PM EDT FRI AUG 21 2009
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
BERKS COUNTY IN EASTERN PENNSYLVANIA...
* UNTIL 115 PM EDT
* AT 1219 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 26
MILES WEST OF WOMELSDORF...OR 29 MILES NORTHWEST OF LANCASTER...AND
MOVING NORTHEAST AT 40 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
STRAUSSTOWN AND 7 MILES NORTHWEST OF BERNVILLE AROUND 105 PM EDT...
HAMBURG AND 7 MILES NORTHWEST OF SHOEMAKERSVILLE AROUND 115 PM
EDT...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT FRIDAY
EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA.
&&
LAT...LON 4053 7634 4052 7630 4054 7618 4060 7605
4059 7603 4064 7601 4068 7591 4050 7563
4026 7607 4036 7621 4036 7624 4047 7640
4050 7644
TIME...MOT...LOC 1620Z 244DEG 33KT 4034 7667
$$
PO1 follow-up statement
000
WWUS51 KPHI 211643
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1243 PM EDT FRI AUG 21 2009
PAC011-211715-
/O.CON.KPHI.SV.W.0211.000000T0000Z-090821T1715Z/
BERKS PA-
1243 PM EDT FRI AUG 21 2009
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM EDT
FOR BERKS COUNTY...
AT 1241 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS
LOCATED 14 MILES WEST OF WOMELSDORF...OR 28 MILES NORTH OF
LANCASTER...MOVING NORTHEAST AT 40 MPH.
THE SEVERE THUNDERSTORM WILL BE NEAR...
STRAUSSTOWN AND 7 MILES NORTHWEST OF BERNVILLE BY 105 PM EDT...
PORT CLINTON...HAMBURG...6 MILES NORTHWEST OF CENTERPORT AND 7
MILES NORTHWEST OF SHOEMAKERSVILLE BY 115 PM EDT...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT FRIDAY
EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA. A SEVERE
THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW
JERSEY.
&&
LAT...LON 4053 7634 4052 7630 4054 7618 4060 7605
4059 7603 4064 7601 4068 7591 4050 7563
4026 7607 4036 7621 4036 7624 4047 7640
4050 7644
TIME...MOT...LOC 1643Z 244DEG 33KT 4043 7642
$$
OHARAThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 12:55 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 35 min |
| Aug 21, 1:16 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 59 min |
| Aug 21, 1:29 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Lehigh, Monroe, Northampton | 76 min |
| Aug 21, 1:52 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 68 min |
| Aug 21, 1:55 PM EDT | Severe Thunderstorm Warning | PHI | Monroe | 65 min |
| Aug 21, 2:41 PM EDT | Areal Flood Advisory | PHI | Monroe, Northampton | 3 hr |
| Aug 21, 2:47 PM EDT | Flash Flood Watch | PHI | Berks, Carbon, Delaware, Lehigh, Monroe, Northampton and 1 more | 35 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2009Every severe thunderstorm 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.