Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 152, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 8, 2021, 5:21 PM EDT for 4 counties in Pennsylvania. It was in force for 39 min. 13 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
- Jul 8, 2021, 5:21 PM EDT (21:21 UTC)
- Expired
- Jul 8, 2021, 6:00 PM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 91 km from the middle of the area, began a volume at 21:23 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 |
|---|---|---|---|
| Jul 8, 5:25 PM EDT | HAIL 0.7 | Springfield, PA | TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:28 PM EDT | TSTM WND DMG | 2 Ene Chester Heights, PA | DOWNED TREES BLOCKING HOLLOW RD. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:38 PM EDT | TSTM WND DMG | Wynnewood, PA | DOWNED TREE LIMBS BLOCKED CEDAR GROVE RD. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:43 PM EDT | TSTM WND DMG | 1 Wnw Wayne, PA | TREE AND WIRES DOWN ON POPLAR AVE. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:44 PM EDT | TSTM WND DMG | Wayne, PA | TREE AND WIRES DOWN ON HILAIRE RD. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:45 PM EDT | FUNNEL CLOUD | Wayne, PA | SOCIAL MEDIA PHOTO OF A SMALL, THIN FUNNEL CLOUD. EXTENDED LESS THAN A QUARTER WAY TO THE GROUND. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:45 PM EDT | TSTM WND DMG | 2 Wnw Wayne, PA | WIRES DOWN ON DEEPDALE RD BLOCKING THE ROAD. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:46 PM EDT | TSTM WND DMG | Wayne, PA | TREE AND WIRES DOWN ON IVEN AVE. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:47 PM EDT | TSTM WND DMG | 2 Sse King Of Prussia, PA | DOWNED TREE AND WIRES ON SEATON ROSS RD AT IVYWOOD LN. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:47 PM EDT | TSTM WND DMG | Conshohocken, PA | TREE DOWN BLOCKING WOOD ST AT 12TH AVE. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:50 PM EDT | TSTM WND DMG | 1 Ese West Conshohocken, PA | TREE DOWN PARTIALLY BLOCKING AVIGNON DR AT CLUB HOUSE RD. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:50 PM EDT | TSTM WND DMG | 1 Se Plymouth Twp, PA | DOWNED TREE BLOCKING GAWAIN RD AT CAMELOT DR. TIME ESTIMATED FROM RADAR. |
| Jul 8, 5:56 PM EDT | TSTM WND DMG | 1 Ene Plymouth Twp, PA | TREE DOWN ON WIRES BLOCKING JOLLY RD AT BEACON HILL CIRCLE. TIME ESTIMATED FROM RADAR. |
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 |
|---|---|---|---|
| Jul 8, 2:09 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 9.4 hours before the alert went out and 202 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
- 272 J/kg
- Mixed-layer CIN
- -99 J/kg
- Mixed-layer LCL
- 1291 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 18 m²/s²
- 0-3 km storm-relative helicity
- 96 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
391
WUUS51 KPHI 082121
SVRPHI
PAC029-045-091-101-082200-
/O.NEW.KPHI.SV.W.0152.210708T2121Z-210708T2200Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
521 PM EDT Thu Jul 8 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Southeastern Montgomery County in southeastern Pennsylvania...
Eastern Chester County in southeastern Pennsylvania...
Northwestern Philadelphia County in southeastern Pennsylvania...
Delaware County in southeastern Pennsylvania...
* Until 600 PM EDT.
* At 521 PM EDT, a severe thunderstorm was located over Concordville,
or 8 miles southeast of West Chester, moving northeast at 35 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
Philadelphia, West Chester, Norristown, Chester, Phoenixville, West
Norriton, East Norriton, Westtown, Conshohocken, Ambler,
Swarthmore, Collegeville, Narberth, Trappe, Cheyney, Elam, Bryn
Mawr, Trout Lake, Chelsea and Radnor Township.
This includes the following highways...
Pennsylvania Turnpike between mile markers 319 and 339.
Northeast Extension between mile markers 21 and 24.
Interstate 95 in Pennsylvania between mile markers 0 and 5.
Interstate 76 in Pennsylvania between mile markers 327 and 337.
Interstate 476 in Pennsylvania between mile markers 1 and 19.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4023 7551 4013 7515 3980 7541 3984 7550
3983 7560 3984 7563
TIME...MOT...LOC 2121Z 204DEG 30KT 3988 7549
HAIL...0.75IN
WIND...60MPH
$$
JEO2 follow-up statements
324
WWUS51 KPHI 082139
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
539 PM EDT Thu Jul 8 2021
PAC029-045-091-101-082200-
/O.CON.KPHI.SV.W.0152.000000T0000Z-210708T2200Z/
Montgomery PA-Chester PA-Philadelphia PA-Delaware PA-
539 PM EDT Thu Jul 8 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR SOUTHEASTERN MONTGOMERY...NORTHEASTERN CHESTER...NORTHWESTERN
PHILADELPHIA AND CENTRAL DELAWARE COUNTIES...
At 539 PM EDT, a severe thunderstorm was located over Radnor
Township, or 11 miles east of West Chester, moving northeast at 35
mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
Philadelphia, Norristown, Phoenixville, West Norriton, East Norriton,
Conshohocken, Ambler, Swarthmore, Collegeville, Narberth, Trappe,
Bryn Mawr, Lima, Trout Lake, Radnor Township, Gradyville, Valley
Forge, Broomall, Plymouth Meeting and Paoli.
This includes the following highways...
Pennsylvania Turnpike between mile markers 319 and 339.
Northeast Extension between mile markers 21 and 24.
Interstate 76 in Pennsylvania between mile markers 327 and 337.
Interstate 476 in Pennsylvania between mile markers 3 and 19.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4023 7551 4013 7515 3990 7533 3992 7545
3996 7559
TIME...MOT...LOC 2139Z 204DEG 30KT 4002 7541
HAIL...0.75IN
WIND...60MPH
$$
JEO144
WWUS51 KPHI 082155
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
555 PM EDT Thu Jul 8 2021
PAC029-045-091-101-082205-
/O.EXP.KPHI.SV.W.0152.000000T0000Z-210708T2200Z/
Montgomery PA-Chester PA-Philadelphia PA-Delaware PA-
555 PM EDT Thu Jul 8 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MONTGOMERY...
NORTHEASTERN CHESTER...NORTHWESTERN PHILADELPHIA AND CENTRAL DELAWARE
COUNTIES WILL EXPIRE AT 600 PM EDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds are still possible with this thunderstorm.
A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
southeastern Pennsylvania.
LAT...LON 4023 7551 4013 7515 3990 7533 3992 7545
3996 7559
TIME...MOT...LOC 2155Z 204DEG 30KT 4013 7535
$$
JEOThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 11:11 PM EDT | Special Weather Statement | PHI | Monroe | 49 min |
| Jul 8, 8:53 AM EDT | Special Weather Statement | PHI | Monroe | 52 min |
| Jul 8, 9:31 AM EDT | Areal Flood Advisory | PHI | Carbon, Monroe | 119 min |
| Jul 8, 9:46 AM EDT | Special Weather Statement | PHI | Monroe | 44 min |
| Jul 8, 1:49 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 41 min |
| Jul 8, 3:50 PM EDT | Special Weather Statement | PHI | Berks | 25 min |
| Jul 8, 4:06 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Montgomery | 39 min |
| Jul 8, 4:25 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 50 min |
| Jul 8, 4:45 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Lehigh, Montgomery, Northampton | 45 min |
| Jul 8, 4:51 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 54 min |
| Jul 8, 5:11 PM EDT | Special Weather Statement | PHI | Lehigh | 34 min |
| Jul 8, 5:29 PM EDT | Special Weather Statement | PHI | Northampton | 46 min |
| Jul 8, 5:52 PM EDT | Special Weather Statement | PHI | Berks | 23 min |
| Jul 8, 6:06 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery | 39 min |
| Jul 8, 6:16 PM EDT | Severe Thunderstorm Warning | PHI | Northampton | 44 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2021Every severe thunderstorm 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.