Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2018
Severe Thunderstorm Warning 38, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 18, 2018, 7:41 PM EDT for 5 counties in Pennsylvania; Hunterdon County, New Jersey. It was in force for 64 min. 6 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
- Jun 18, 2018, 7:41 PM EDT (23:41 UTC)
- Expired
- Jun 18, 2018, 8:45 PM EDT
- In force
- 64 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Hunterdon County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 77 km from the middle of the area, began a volume at 23:43 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 |
|---|---|---|---|
| Jun 18, 8:07 PM EDT | TSTM WND DMG | Kingwood Twp, NJ | 12+ INCHES IN DIAMETER OAK TREE SNAPPED OFF APPROXIMATELY 10 FEET ABOVE THE GROUND. TIME ESTIMATED FROM RADAR. |
| Jun 18, 8:15 PM EDT | TSTM WND DMG | Skippack, PA | TREE DOWN BLOCKING ROADWAY. |
| Jun 18, 8:25 PM EDT | TSTM WND DMG | Towamencin Twp, PA | TREES AND WIRES DOWN. |
| Jun 18, 8:25 PM EDT | TSTM WND DMG | Worcester, PA | TREES AND WIRES DOWN. |
| Jun 18, 8:30 PM EDT | TSTM WND DMG | East Norriton, PA | TREES AND WIRES DOWN. |
| Jun 18, 8:30 PM EDT | TSTM WND DMG | Lower Gwynedd Twp, PA | TREES AND WIRES DOWN. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 11.7 hours before the alert went out and 208 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1413 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 122 m²/s²
- 0-3 km storm-relative helicity
- 123 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
424
WUUS51 KPHI 182341
SVRPHI
NJC019-PAC011-017-029-077-091-190045-
/O.NEW.KPHI.SV.W.0038.180618T2341Z-180619T0045Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
741 PM EDT MON JUN 18 2018
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Southeastern Hunterdon County in northwestern New Jersey...
Southeastern Berks County in eastern Pennsylvania...
Montgomery County in southeastern Pennsylvania...
Southeastern Lehigh County in eastern Pennsylvania...
Bucks County in southeastern Pennsylvania...
Northeastern Chester County in southeastern Pennsylvania...
* Until 845 PM EDT.
* At 740 PM EDT, severe thunderstorms were located along a line
extending from near Hellertown to near New Morgan, 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...
Norristown, Pottstown, Phoenixville, Lansdale, West Norriton, East
Norriton, Quakertown, Perkasie, Doylestown, Byram, Conshohocken,
Souderton, Bedminster, Ambler, Birdsboro, Collegeville, Royersford,
Chalfont, Tinicum and Trappe.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
In addition to damaging winds, frequent cloud to ground lightning is
occurring with this storm. Move indoors immediately. Remember, if
you can hear thunder, you are close enough to be struck by lightning.
&&
LAT...LON 4056 7541 4044 7475 4041 7481 4038 7481
4038 7487 4035 7486 4034 7493 4032 7490
4004 7534 4006 7536 4005 7540 3998 7545
4012 7585 4022 7600
TIME...MOT...LOC 2340Z 288DEG 31KT 4054 7535 4022 7588
HAIL...<.75IN
WIND...60MPH
$$
Iovino1 follow-up statement
961
WWUS51 KPHI 190031
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
831 PM EDT MON JUN 18 2018
PAC011-077-190039-
/O.CAN.KPHI.SV.W.0038.000000T0000Z-180619T0045Z/
Berks PA-Lehigh PA-
831 PM EDT MON JUN 18 2018
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BERKS AND
SOUTHERN LEHIGH COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.
LAT...LON 4025 7569 4031 7564 4033 7530 4047 7491
4044 7476 4041 7481 4038 7481 4038 7487
4035 7486 4033 7494 4032 7492 4032 7491
4004 7534 4006 7536 4005 7540 3998 7545
4012 7585
TIME...MOT...LOC 0029Z 288DEG 31KT 4041 7484 4009 7537
$$
NJC019-PAC017-029-091-190045-
/O.CON.KPHI.SV.W.0038.000000T0000Z-180619T0045Z/
Hunterdon NJ-Montgomery PA-Bucks PA-Chester PA-
831 PM EDT MON JUN 18 2018
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM EDT
FOR SOUTHEASTERN HUNTERDON...MONTGOMERY...CENTRAL BUCKS AND
NORTHEASTERN CHESTER COUNTIES...
At 829 PM EDT, severe thunderstorms were located along a line
extending from near Stockton in New Jersey to near Pottstown in
Pennsylvania, 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...
Norristown, Pottstown, Phoenixville, Lansdale, West Norriton, East
Norriton, Doylestown, Conshohocken, Souderton, Ambler, Collegeville,
Royersford, Chalfont, Trappe, Hatfield, New Hope, Schwenksville,
Ivyland, Stockton and Fricks.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4025 7569 4031 7564 4033 7530 4047 7491
4044 7476 4041 7481 4038 7481 4038 7487
4035 7486 4033 7494 4032 7492 4032 7491
4004 7534 4006 7536 4005 7540 3998 7545
4012 7585
TIME...MOT...LOC 0029Z 288DEG 31KT 4041 7484 4009 7537
HAIL...<.75IN
WIND...60MPH
$$
IovinoThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 18, 5:46 PM EDT | Special Weather Statement | PHI | Carbon, Monroe | 44 min |
| Jun 18, 6:10 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 50 min |
| Jun 18, 6:37 PM EDT | Special Weather Statement | PHI | Lehigh, Northampton | 53 min |
| Jun 18, 6:48 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Lehigh, Monroe, Northampton | 57 min |
| Jun 18, 6:56 PM EDT | Special Weather Statement | PHI | Berks, Lehigh | 64 min |
| Jun 18, 6:58 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh | 62 min |
| Jun 18, 7:30 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Northampton | 60 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2018Severe Thunderstorm Warnings in New Jersey, 2018Every severe thunderstorm warning in 2018
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.