Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 187, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 22, 2017, 10:07 PM EDT for 4 states. It was in force for 53 min. 9 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 22, 2017, 10:07 PM EDT (02:07 UTC)
- Expired
- Aug 22, 2017, 11:00 PM EDT
- In force
- 53 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties New Castle County, DE, Cecil County, MD, Kent County, MD, Gloucester County, NJ, Salem County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Dover AFB radar (KDOX), 96 km from the middle of the area, began a volume at 02:06 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 22, 10:15 PM EDT | HAIL 0.88 | Cedarville, PA | |
| Aug 22, 10:48 PM EDT | TSTM WND DMG | Media, PA | 12 FOOT TREE LIMB DOWN AT THE DELAWARE COUNTY OEM BUILDING. TIME ESTIMATED FROM RADAR. |
| Aug 22, 10:50 PM EDT | TSTM WND DMG | Kennett Square, PA | A TREE FELL ONTO A HOME WHICH TRAPPED PEOPLE INSIDE. |
| Aug 22, 11:00 PM EDT | TSTM WND DMG | Haverford Twp, PA | LARGE TREE BRANCH REPORTED DOWN ON A FENCE IN HAVERFORD TOWNSHIP. TIME ESTIMATED FROM RADAR. |
| Aug 22, 11:05 PM EDT | TSTM WND DMG | 1 Nne Highland Park, PA | LARGE TREE BRANCH REPORTED DOWN AND BLOCKING THE STREET. TIME ESTIMATED FROM RADAR. PUBLIC REPORT RELAYED BY OEM. |
| Aug 22, 11:05 PM EDT | TSTM WND DMG | Sw Philadelphia, PA | SOME TREES BLOWN DOWN ACROSS PORTIONS OF SOUTHWEST PHILADELPHIA. TIME ESTIMATED FROM RADAR. |
| Aug 22, 11:06 PM EDT | TSTM WND DMG | Rittenhouse, PA | TREE REPORTED DOWN AND BLOCKING THE INTERSECTION OF LOMBARD STREET AND 17TH STREET. TIME ESTIMATED FROM RADAR. PUBLIC REPORT RELAYED BY OEM. |
| Aug 22, 11:08 PM EDT | TSTM WND DMG | Wynnefield Heights, PA | LARGE TREE BRANCH REPORTED DOWN AND BLOCKING THE SIDEWALK. TIME ESTIMATED FROM RADAR. PUBLIC REPORT RELAYED BY OEM. |
| Aug 22, 11:10 PM EDT | TSTM WND DMG | Wilmington, DE | SEVERAL LARGE BRANCHES BLOWN DOWN. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
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 22, 4:19 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 2.1 hours before the alert went out and 176 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
- 550 J/kg
- Mixed-layer CIN
- -36 J/kg
- Mixed-layer LCL
- 1559 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 134 m²/s²
- 0-3 km storm-relative helicity
- 248 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.1
The text
As transmitted.
185
WUUS51 KPHI 230207
SVRPHI
DEC003-MDC015-029-NJC015-033-PAC011-017-029-045-091-101-230300-
/O.NEW.KPHI.SV.W.0187.170823T0207Z-170823T0300Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1007 PM EDT TUE AUG 22 2017
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
New Castle County in northern Delaware...
Northeastern Kent County in northeastern Maryland...
Cecil County in northeastern Maryland...
Salem County in southern New Jersey...
Northwestern Gloucester County in southern New Jersey...
Southeastern Berks County in eastern Pennsylvania...
Montgomery County in southeastern Pennsylvania...
Southern Bucks County in southeastern Pennsylvania...
Chester County in southeastern Pennsylvania...
Philadelphia County in southeastern Pennsylvania...
Delaware County in southeastern Pennsylvania...
* Until 1100 PM EDT
* At 1007 PM EDT, severe thunderstorms were located along a line
extending from near Elverson to near Pleasant Hills, moving east at
55 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Minor damage to vehicles is possible. Expect damage to
trees and power lines.
* Locations impacted include...
Philadelphia, Camden, Wilmington, Newark, Middletown, West Chester,
Elkton, Gloucester City, Calvert, Bensalem, Ewing, Norristown,
Chester, Deptford, Pottstown, West Deptford, Phoenixville,
Lansdale, West Norriton and East Norriton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3976 7606 3991 7600 4036 7564 4026 7485
4024 7482 4006 7494 3995 7514 3984 7508
3949 7531 3945 7542 3934 7541 3939 7549
3931 7543 3936 7551 3932 7558 3937 7612
3937 7606 3952 7598 3955 7608 3967 7619
TIME...MOT...LOC 0207Z 267DEG 47KT 4017 7578 3948 7636
HAIL...1.00IN
WIND...60MPH
$$
MWG2 follow-up statements
998
WWUS51 KPHI 230242
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
1042 PM EDT TUE AUG 22 2017
DEC003-MDC015-029-NJC015-033-PAC011-017-029-045-091-101-230300-
/O.CON.KPHI.SV.W.0187.000000T0000Z-170823T0300Z/
New Castle DE-Kent MD-Cecil MD-Salem NJ-Gloucester NJ-Berks PA-
Montgomery PA-Bucks PA-Chester PA-Philadelphia PA-Delaware PA-
1042 PM EDT TUE AUG 22 2017
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR NEW CASTLE...NORTHEASTERN KENT...CECIL...SALEM...NORTHWESTERN
GLOUCESTER...SOUTHEASTERN BERKS...MONTGOMERY...SOUTHERN BUCKS...
CHESTER...PHILADELPHIA AND DELAWARE COUNTIES...
At 1042 PM EDT, severe thunderstorms were located along a line
extending from near Schwenksville to Charlestown, moving east at 45
mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Minor damage to vehicles is possible. Expect damage to
trees and power lines.
Locations impacted include...
Philadelphia, Camden, Wilmington, Newark, Middletown, West Chester,
Elkton, Gloucester City, Calvert, Bensalem, Ewing, Norristown,
Chester, Deptford, Pottstown, West Deptford, Phoenixville, Lansdale,
West Norriton and East Norriton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 3976 7606 3991 7600 4036 7564 4026 7485
4024 7482 4006 7494 3995 7514 3984 7508
3949 7531 3945 7542 3934 7541 3939 7549
3931 7543 3936 7551 3932 7558 3937 7612
3937 7606 3952 7598 3955 7608 3967 7619
TIME...MOT...LOC 0242Z 263DEG 40KT 4024 7538 3955 7596
HAIL...1.00IN
WIND...60MPH
$$
SFJ910
WWUS51 KPHI 230300
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
1100 PM EDT TUE AUG 22 2017
DEC003-MDC015-029-NJC015-033-PAC011-017-029-045-091-101-230309-
/O.EXP.KPHI.SV.W.0187.000000T0000Z-170823T0300Z/
New Castle DE-Kent MD-Cecil MD-Salem NJ-Gloucester NJ-Berks PA-
Montgomery PA-Bucks PA-Chester PA-Philadelphia PA-Delaware PA-
1100 PM EDT TUE AUG 22 2017
...THE SEVERE THUNDERSTORM WARNING FOR NEW CASTLE...NORTHEASTERN
KENT...CECIL...SALEM...NORTHWESTERN GLOUCESTER...SOUTHEASTERN
BERKS...MONTGOMERY...SOUTHERN BUCKS...CHESTER...PHILADELPHIA AND
DELAWARE COUNTIES WILL EXPIRE AT 1100 PM EDT...
The storms which prompted the warning are still moving through the
area and a new warning has been issued further east of the prior
warning.
A severe thunderstorm watch remains in effect until midnight EDT for
northern Delaware...northeastern Maryland...southern and central New
Jersey...and eastern and southeastern Pennsylvania.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
in Mount Holly NJ.
LAT...LON 3976 7606 3991 7600 4036 7564 4026 7485
4024 7482 4006 7494 3995 7514 3984 7508
3949 7531 3945 7542 3934 7541 3939 7549
3931 7543 3936 7551 3932 7558 3937 7612
3937 7606 3952 7598 3955 7608 3967 7619
TIME...MOT...LOC 0259Z 267DEG 47KT 4025 7512 3956 7570
$$
MWGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 22, 10:40 PM EDT | Areal Flood Advisory | PHI | New Castle | 4 hr |
| Aug 22, 10:58 PM EDT | Severe Thunderstorm Warning | PHI | Kent, New Castle | 62 min |
| Aug 22, 11:46 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 44 min |
| Aug 23, 12:06 AM EDT | Flash Flood Warning | PHI | New Castle | 4 hr |
| Aug 23, 1:56 AM EDT | Areal Flood Advisory | PHI | New Castle | 4 hr |
| Aug 23, 4:02 AM EDT | Areal Flood Warning | PHI | New Castle | 4 hr |
| Aug 22, 8:12 PM EDT | Severe Thunderstorm Warning | PHI | Monroe, Northampton | 48 min |
| Aug 22, 8:15 PM EDT | Tornado Warning | PHI | Monroe, Northampton | 30 min |
| Aug 22, 8:45 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more | 60 min |
| Aug 22, 8:58 PM EDT | Severe Thunderstorm Warning | PHI | Monroe, Northampton | 24 min |
| Aug 22, 9:18 PM EDT | Areal Flood Advisory | PHI | Berks, Montgomery | 4 hr |
| Aug 22, 9:23 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Montgomery | 52 min |
| Aug 22, 9:40 PM EDT | Tornado Warning | PHI | Berks, Chester, Montgomery | 20 min |
| Aug 22, 9:42 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery | 48 min |
| Aug 22, 10:27 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery | 48 min |
| Aug 22, 10:37 PM EDT | Areal Flood Advisory | PHI | Berks, Bucks, Lehigh, Montgomery, Northampton | 4 hr |
| Aug 23, 12:29 AM EDT | Severe Thunderstorm Warning | PHI | Philadelphia | 46 min |
| Aug 22, 11:30 PM EDT | Special Weather Statement | PHI | Cecil | 30 min |
| Aug 22, 8:20 PM EDT | Special Weather Statement | PHI | Sussex | 40 min |
| Aug 22, 10:13 PM EDT | Special Marine Warning | PHI | 92 min | |
| Aug 22, 11:39 PM EDT | Special Marine Warning | PHI | 66 min | |
| Aug 22, 11:42 PM EDT | Flash Flood Warning | PHI | Hunterdon, Middlesex, Somerset | 4 hr |
| Aug 23, 12:37 AM EDT | Areal Flood Advisory | PHI | Burlington, Camden, Gloucester, Mercer, Middlesex, Monmouth and 1 more | 4 hr |
| Aug 23, 2:43 AM EDT | Areal Flood Advisory | PHI | Atlantic, Burlington, Camden, Cumberland, Gloucester, Ocean and 1 more | 4 hr |
| Aug 23, 3:37 AM EDT | Areal Flood Warning | PHI | Hunterdon, Middlesex, Somerset | 4 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2017Severe Thunderstorm Warnings in Maryland, 2017Severe Thunderstorm Warnings in New Jersey, 2017Every severe thunderstorm warning in 2017
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.