Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 202, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2009, 6:48 PM EDT for Cecil County, Maryland; Berks County, Chester County, Pennsylvania. It was in force for 72 min. 3 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 18, 2009, 6:48 PM EDT (22:48 UTC)
- Expired
- Aug 18, 2009, 8:00 PM EDT
- In force
- 72 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Cecil County, MD, Berks County, PA, Chester County, PA
The radar
The Philadelphia radar (KDIX), 127 km from the middle of the area, began a volume at 22:47 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 18, 6:50 PM EDT | TSTM WND DMG | 1 Se Blake, MD | TREES DOWN ON LITTLE ELK CREEK |
| Aug 18, 6:50 PM EDT | TSTM WND DMG | 3 Nnw Cherry Hill, MD | TREES AND WIRES DOWN IN TOWN OF FAIR HILL. |
| Aug 18, 7:00 PM EDT | TSTM WND DMG | 2 S Oxford, PA | NUMEROUS TREES DOWN SOUTH OF OXFORD. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.8 hours before the alert went out and 59 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
- 810 J/kg
- Mixed-layer CIN
- -78 J/kg
- Mixed-layer LCL
- 1015 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 14 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
WUUS51 KPHI 182248
SVRPHI
MDC015-PAC011-029-190000-
/O.NEW.KPHI.SV.W.0202.090818T2248Z-090819T0000Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
648 PM EDT TUE AUG 18 2009
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
SOUTHERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
THIS INCLUDES THE CITY OF READING...
NORTHERN CECIL COUNTY IN NORTHEAST MARYLAND...
THIS INCLUDES THE CITY OF ELKTON...
CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
THIS INCLUDES THE CITY OF WEST CHESTER...
* UNTIL 800 PM EDT
* AT 644 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
DESTRUCTIVE WINDS IN EXCESS OF 70 MPH. THIS STORM WAS LOCATED 12
MILES WEST OF HONEY BROOK...OR 12 MILES NORTHEAST OF LANCASTER...
AND MOVING EAST AT 30 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
HONEY BROOK AROUND 705 PM EDT...
NEW MORGAN AND ELVERSON AROUND 715 PM EDT...
7 MILES NORTH OF GLENMOORE AROUND 720 PM EDT...
BIRDSBORO AROUND 725 PM EDT...
PUGHTOWN AROUND 735 PM EDT...
9 MILES NORTH OF CHESTER SPRINGS AROUND 740 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 GREATEST KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
&&
LAT...LON 4039 7626 4045 7554 4024 7573 4020 7560
4005 7544 3985 7564 3982 7572 3971 7581
3955 7579 3956 7610 3972 7624 3973 7615
3978 7607 3987 7601 3992 7601 4003 7595
4011 7595 4014 7590
TIME...MOT...LOC 2248Z 257DEG 24KT 4015 7609
$$
NIERENBERG1 follow-up statement
000
WWUS51 KPHI 182341
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
741 PM EDT TUE AUG 18 2009
MDC015-182352-
/O.CAN.KPHI.SV.W.0202.000000T0000Z-090819T0000Z/
CECIL MD-
741 PM EDT TUE AUG 18 2009
...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CECIL COUNTY IS
CANCELLED...
LAT...LON 4039 7626 4045 7554 4024 7573 4020 7560
4005 7544 3985 7564 3987 7572 3986 7585
3987 7601 3992 7601 4003 7595 4011 7595
4014 7590
TIME...MOT...LOC 2342Z 257DEG 24KT 4023 7563
$$
PAC011-029-190000-
/O.CON.KPHI.SV.W.0202.000000T0000Z-090819T0000Z/
CHESTER PA-BERKS PA-
741 PM EDT TUE AUG 18 2009
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR SOUTHERN BERKS AND CHESTER COUNTIES...
AT 741 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE
HAIL...AND DESTRUCTIVE WINDS IN EXCESS OF 70 MPH. THIS STORM WAS
LOCATED NEAR PUGHTOWN...OR 17 MILES SOUTHEAST OF READING...MOVING
EAST AT 30 MPH.
LAT...LON 4039 7626 4045 7554 4024 7573 4020 7560
4005 7544 3985 7564 3987 7572 3986 7585
3987 7601 3992 7601 4003 7595 4011 7595
4014 7590
TIME...MOT...LOC 2342Z 257DEG 24KT 4023 7563
$$
NIERENBERGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 5:45 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 60 min |
| Aug 18, 7:22 PM EDT | Severe Thunderstorm Warning | PHI | Delaware | 53 min |
| Aug 18, 7:37 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 68 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2009Severe Thunderstorm Warnings in Maryland, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.