Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008
Severe Thunderstorm Warning 210, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 10, 2008, 10:18 AM EDT for Chester County, Pennsylvania. It was in force for 57 min. 4 reports 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
- Aug 10, 2008, 10:18 AM EDT (14:18 UTC)
- Expired
- Aug 10, 2008, 11:15 AM EDT
- In force
- 57 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 116 km from the middle of the area, began a volume at 14:20 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 |
|---|---|---|---|
| Aug 10, 11:03 AM EDT | HAIL 0.88 | 2 Se Coatesville, PA | |
| Aug 10, 11:10 AM EDT | HAIL 1.75 | 2 Se Exton, PA | |
| Aug 10, 11:15 AM EDT | HAIL 0.88 | Exton, PA | |
| Aug 10, 11:15 AM EDT | HAIL 2 | West Chester, PA |
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, 2.3 hours before the alert went out and 184 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
- 771 J/kg
- Mixed-layer CIN
- -66 J/kg
- Mixed-layer LCL
- 923 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 3 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS51 KPHI 101418 SVRPHI PAC029-101515- /O.NEW.KPHI.SV.W.0210.080810T1418Z-080810T1515Z/ BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1018 AM EDT SUN AUG 10 2008 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA... * UNTIL 1115 AM EDT * AT 1016 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR COCHRANVILLE...AND MOVING NORTHEAST AT 16 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... COATESVILLE BY 1040 AM... MARSHALLTON BY 1055 AM... DOWNINGTOWN BY 1100 AM... GLENMOORE AND WEST CHESTER BY 1105 AM... LIONVILLE AND CHESTER SPRINGS BY 1115 AM... 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. LAT...LON 4019 7574 3999 7547 3982 7589 3989 7598 TIME...MOT...LOC 1418Z 225DEG 14KT 3990 7587 $$ IOVINO
1 follow-up statement
000
WWUS51 KPHI 101459
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1059 AM EDT SUN AUG 10 2008
PAC029-101515-
/O.CON.KPHI.SV.W.0210.000000T0000Z-080810T1515Z/
CHESTER PA-
1059 AM EDT SUN AUG 10 2008
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT
FOR CENTRAL CHESTER COUNTY...
AT 1054 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DESTRUCTIVE WINDS IN EXCESS OF 70 MPH. THIS STORM WAS
LOCATED NEAR THORNDALE...OR 8 MILES NORTHWEST OF WEST CHESTER...
MOVING NORTHEAST AT 16 MPH.
THE SEVERE THUNDERSTORM WILL BE NEAR...
GLENMOORE BY 1105 AM EDT...
8 MILES NORTHWEST OF WEST GOSHEN BY 1110 AM EDT...
LIONVILLE...EXTON AND CHESTER SPRINGS BY 1115 AM EDT...
DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT SUNDAY
EVENING FOR NORTHERN DELAWARE AND NEW JERSEY AND EASTERN
PENNSYLVANIA.
LAT...LON 4008 7583 4018 7573 3999 7547 3985 7582
3994 7594
TIME...MOT...LOC 1459Z 225DEG 14KT 4001 7572
$$
RNSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 10, 10:44 AM EDT | Severe Thunderstorm Warning | PHI | Delaware | 61 min |
| Aug 10, 11:09 AM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 66 min |
| Aug 10, 11:32 AM EDT | Areal Flood Advisory | PHI | Chester, Delaware | 3 hr |
| Aug 10, 11:46 AM EDT | Severe Thunderstorm Warning | PHI | Delaware | 59 min |
| Aug 10, 12:09 PM EDT | Tornado Warning | PHI | Delaware | 36 min |
| Aug 10, 12:17 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery | 4 hr |
| Aug 10, 12:21 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Lehigh, Montgomery | 84 min |
| Aug 10, 12:40 PM EDT | Severe Thunderstorm Warning | PHI | Delaware, Philadelphia | 95 min |
| Aug 10, 1:05 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Carbon, Lehigh, Monroe, Northampton | 115 min |
| Aug 10, 1:10 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Montgomery | 65 min |
| Aug 10, 1:47 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Montgomery | 58 min |
| Aug 10, 3:05 PM EDT | Flash Flood Warning | PHI | Chester | 3 hr |
| Aug 10, 3:35 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 40 min |
| Aug 10, 4:45 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 75 min |
| Aug 10, 5:25 PM EDT | Areal Flood Advisory | PHI | Berks, Montgomery | 110 min |
| Aug 10, 5:45 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware | 75 min |
| Aug 10, 5:59 PM EDT | Areal Flood Advisory | PHI | Chester, Delaware | 2 hr |
| Aug 10, 6:45 PM EDT | Areal Flood Advisory | PHI | Philadelphia | 2 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2008Every severe thunderstorm warning in 2008
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.