Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 106, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 1, 2021, 3:13 PM EDT for 5 counties in Pennsylvania. It was in force for 47 min. 10 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 1, 2021, 3:13 PM EDT (19:13 UTC)
- Expired
- Jul 1, 2021, 4:00 PM EDT
- In force
- 47 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 123 km from the middle of the area, began a volume at 19:13 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 1, 3:13 PM EDT | TSTM WND DMG | 4 Nne West Sadsbury Twp, PA | DOWNED TREE ON LAMMEY ROAD. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:21 PM EDT | TSTM WND DMG | 2 Nnw Geryville, PA | DOWNED WIRES NEAR ELM ROAD. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:21 PM EDT | TSTM WND DMG | 2 Wnw Caln Twp, PA | DOWNED TREE ON FISHERVILLE ROAD. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:23 PM EDT | TSTM WND DMG | 2 Sw Gilbertsville, PA | MPING REPORT OF DOWNED TREE LIMBS AND POWER LINES NEAR ROUTE 100. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:26 PM EDT | TSTM WND DMG | 1 N Coatesville, PA | DOWNED TREES AND WIRES NEAR VALLEY STATION ROAD IN COATESVILLE. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:27 PM EDT | TSTM WND DMG | 1 Ne Thorndale, PA | DOWNED TREE ON BEAVER RUN ROAD. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:31 PM EDT | TSTM WND DMG | 1 W Chester Springs, PA | DOWNED WIRES NEAR HORSESHOE TRAIL. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:47 PM EDT | TSTM WND DMG | 2 Sse East Caln Twp, PA | DOWNED WIRES NEAR PARADISE VALLEY NATURE AREA IN DOWNINGTOWN. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:51 PM EDT | TSTM WND DMG | 1 Wnw Valley Forge, PA | SEVERAL REPORTS OF DOWNED TREE LIMBS AND WIRES NEAR VALLEY FORGE AND PHOENIXVILLE. TIME ESTIMATED FROM RADAR. |
| Jul 1, 3:59 PM EDT | TSTM WND DMG | 2 W North Wales, PA | DOWNED TREES AND WIRES NEAR GARFIELD PARK IN LANSDALE. |
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 1, 12:46 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.2 hours before the alert went out and 179 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
- 604 J/kg
- Mixed-layer CIN
- -48 J/kg
- Mixed-layer LCL
- 928 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 61 m²/s²
- 0-3 km storm-relative helicity
- 108 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.2
The text
As transmitted.
057
WUUS51 KPHI 011913
SVRPHI
PAC011-017-029-077-091-012000-
/O.NEW.KPHI.SV.W.0106.210701T1913Z-210701T2000Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
313 PM EDT Thu Jul 1 2021
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Southeastern Berks County in eastern Pennsylvania...
Southeastern Lehigh County in eastern Pennsylvania...
Montgomery County in southeastern Pennsylvania...
Northwestern Bucks County in southeastern Pennsylvania...
Chester County in southeastern Pennsylvania...
* Until 400 PM EDT.
* At 313 PM EDT, severe thunderstorms were located along a line
extending from Bechtelsville to Glenmoore to near Quarryville,
moving east at 35 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
* Locations impacted include...
West Chester, Pottstown, Phoenixville, Lansdale, West Norriton,
East Norriton, Coatesville, Quakertown, Perkasie, Downingtown,
Souderton, Bedminster, Kennett Square, Birdsboro, Collegeville,
Oxford, Royersford, Parkesburg, Trappe and Hatfield.
This includes the following highways...
Pennsylvania Turnpike between mile markers 299 and 326.
Northeast Extension between mile markers 25 and 47.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3981 7603 3983 7604 3987 7599 3994 7598
3995 7600 4004 7593 4009 7594 4014 7588
4015 7589 4044 7570 4053 7512 4017 7531
3977 7580 3978 7606
TIME...MOT...LOC 1913Z 254DEG 30KT 4037 7565 4010 7579 3985 7614
HAIL...<.75IN
WIND...60MPH
$$
CMS3 follow-up statements
099
WWUS51 KPHI 011931
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
331 PM EDT Thu Jul 1 2021
PAC011-011940-
/O.CAN.KPHI.SV.W.0106.000000T0000Z-210701T2000Z/
Berks PA-
331 PM EDT Thu Jul 1 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BERKS COUNTY IS
CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
southeastern Pennsylvania.
LAT...LON 3983 7604 3987 7599 3995 7600 4004 7593
4009 7594 4015 7586 4018 7574 4047 7552
4053 7512 4017 7531 3977 7580 3978 7605
TIME...MOT...LOC 1930Z 254DEG 30KT 4041 7548 4014 7562 3989 7597
$$
PAC017-029-077-091-012000-
/O.CON.KPHI.SV.W.0106.000000T0000Z-210701T2000Z/
Lehigh PA-Montgomery PA-Bucks PA-Chester PA-
331 PM EDT Thu Jul 1 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR SOUTHEASTERN LEHIGH...MONTGOMERY...NORTHWESTERN BUCKS AND CHESTER
COUNTIES...
At 330 PM EDT, severe thunderstorms were located along a line
extending from Geryville to near Chester Springs to Homeville, moving
east at 35 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
West Chester, Pottstown, Phoenixville, Lansdale, West Norriton, East
Norriton, Coatesville, Quakertown, Perkasie, Downingtown, Souderton,
Bedminster, Kennett Square, Collegeville, Oxford, Royersford,
Parkesburg, Trappe, Hatfield and East Greenville.
This includes the following highways...
Pennsylvania Turnpike between mile markers 300 and 326.
Northeast Extension between mile markers 25 and 47.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Frequent cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.
&&
LAT...LON 3983 7604 3987 7599 3995 7600 4004 7593
4009 7594 4015 7586 4018 7574 4047 7552
4053 7512 4017 7531 3977 7580 3978 7605
TIME...MOT...LOC 1930Z 254DEG 30KT 4041 7548 4014 7562 3989 7597
HAIL...<.75IN
WIND...60MPH
$$
CMS185
WWUS51 KPHI 011941
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
341 PM EDT Thu Jul 1 2021
PAC017-029-077-091-012000-
/O.CON.KPHI.SV.W.0106.000000T0000Z-210701T2000Z/
Lehigh PA-Montgomery PA-Bucks PA-Chester PA-
341 PM EDT Thu Jul 1 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR SOUTHEASTERN LEHIGH...MONTGOMERY...NORTHWESTERN BUCKS AND CHESTER
COUNTIES...
At 340 PM EDT, severe thunderstorms were located along a line
extending from Quakertown to Phoenixville to near Cochranville,
moving east at 35 mph. The most dangerous part of the storm was near
Chester Springs.
HAZARD...60 mph wind gusts.
SOURCE...Law enforcement. Trees were reported downed in West Caln
Township.
IMPACT...Damage to roofs, siding, trees, and power lines is
possible.
Locations impacted include...
West Chester, Pottstown, Phoenixville, Lansdale, West Norriton, East
Norriton, Coatesville, Quakertown, Perkasie, Downingtown, Souderton,
Bedminster, Kennett Square, Collegeville, Oxford, Royersford,
Parkesburg, Trappe, Hatfield and East Greenville.
This includes the following highways...
Pennsylvania Turnpike between mile markers 300 and 326.
Northeast Extension between mile markers 25 and 47.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3983 7604 3987 7599 3995 7600 4004 7593
4009 7594 4015 7586 4018 7574 4047 7552
4053 7512 4017 7531 3977 7580 3978 7605
TIME...MOT...LOC 1940Z 270DEG 30KT 4043 7538 4016 7552 3991 7587
TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
$$
CMS103
WWUS51 KPHI 012002
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
402 PM EDT Thu Jul 1 2021
PAC017-029-077-091-012012-
/O.EXP.KPHI.SV.W.0106.000000T0000Z-210701T2000Z/
Lehigh PA-Montgomery PA-Bucks PA-Chester PA-
402 PM EDT Thu Jul 1 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LEHIGH...
MONTGOMERY...NORTHWESTERN BUCKS AND CHESTER COUNTIES HAS EXPIRED...
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire. However, gusty
winds are still possible with these thunderstorms.
A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
southeastern Pennsylvania.
LAT...LON 3983 7604 3987 7599 3995 7600 4004 7593
4009 7594 4015 7586 4018 7574 4047 7552
4053 7512 4017 7531 3977 7580 3978 7605
TIME...MOT...LOC 2002Z 254DEG 30KT 4048 7515 4021 7530 3996 7565
$$
CMSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 8:16 PM EDT | Special Weather Statement | PHI | Bucks, Montgomery | 44 min |
| Jun 30, 8:37 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 38 min |
| Jul 1, 2:51 PM EDT | Special Weather Statement | PHI | Chester, Montgomery | 39 min |
| Jul 1, 3:23 PM EDT | Areal Flood Advisory | PHI | Chester, Montgomery | 77 min |
| Jul 1, 3:48 PM EDT | Areal Flood Advisory | PHI | Bucks, Delaware, Montgomery, Philadelphia | 112 min |
| Jul 1, 3:50 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 40 min |
| Jul 1, 4:27 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 48 min |
| Jul 1, 4:59 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Philadelphia | 46 min |
| Jul 1, 5:02 PM EDT | Tornado Warning | PHI | Bucks | 28 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.