Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 183, NWS Philadelphia/Mount Holly

August 22, 20178 counties in Pennsylvania; Hunterdon County, Somerset County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 22, 2017, 8:45 PM EDT for 8 counties in Pennsylvania; Hunterdon County, Somerset County, Warren County, New Jersey. It was in force for 60 min. 15 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, 8:45 PM EDT (00:45 UTC)
Expired: Aug 22, 2017, 9:45 PM EDT
In force: 60 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 1.75 in
Wind: 70.0 mph

Counties Hunterdon County, NJ, Somerset County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 111 km from the middle of the area, began a volume at 00:48 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, 8:45 PM EDT	TSTM WND DMG	3 W Fleetwood, PA	TREES SNAPPED AND SOME UPROOTED.
Aug 22, 8:50 PM EDT	TSTM WND DMG	Hanover Twp, PA	SEVERAL TREES REPORTED DOWN IN HANOVER TOWNSHIP.
Aug 22, 8:50 PM EDT	TSTM WND DMG	Lehigh Twp, PA	TREES AND WIRES DOWN. TIME ESTIMATED FROM RADAR.
Aug 22, 8:50 PM EDT	TSTM WND GST 50	Kutztown, PA	THUNDERSTORM WIND GUSTS ESTIMATED TO AROUND 50 MPH.
Aug 22, 8:50 PM EDT	HAIL 0.75	Kutztown, PA
Aug 22, 8:58 PM EDT	TSTM WND DMG	North Catasauqua, PA	TREE DOWNED BY WIND AT NORTH CATASAUQUA PLAYGROUND. TIME ESTIMATED BY RADAR.
Aug 22, 8:58 PM EDT	TSTM WND GST 51	Catasauqua, PA
Aug 22, 9:00 PM EDT	TSTM WND GST 53	1 Ne Weisenberg Twp, PA	NEAR NEW TRIPOLI.
Aug 22, 9:03 PM EDT	TSTM WND GST 47	Lehigh Valley Intl Airp, PA
Aug 22, 9:32 PM EDT	TSTM WND DMG	1 S Reading, PA	A TREE FELL ONTO A PROPANE TANK.
Aug 22, 9:32 PM EDT	TSTM WND GST 60	Exeter Twp, PA
Aug 22, 9:35 PM EDT	TSTM WND DMG	Alexandria Twp, NJ	TREE AND WIRES DOWN AND ON FIRE. TIMES ESTIMATED FROM RADAR.
Aug 22, 9:36 PM EDT	TSTM WND DMG	Glen Gardner, NJ	TREES AND WIRES REPORTED DOWN IN GLEN GARDNER... CALIFON... AND LEBANON TOWNSHIP. TIME ESTIMATED FROM RADAR.
Aug 22, 9:45 PM EDT	TSTM WND DMG	Holland Twp, NJ	TREES DOWN AND WIRES SPARKING ON MILFORD WARREN GLEN ROAD. TIMES ESTIMATED FROM RADAR.
Aug 22, 9:53 PM EDT	TSTM WND DMG	Flemington, NJ	TREE DOWN ONTO A CAR. NO INJURIES REPORTED. 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
Aug 22, 4:19 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 0.8 hours before the alert went out and 218 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1278 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 845 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 171 m²/s²
0-3 km storm-relative helicity: 220 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 4.6

Open this sounding in Storm Lab

The text

As transmitted.

528 
WUUS51 KPHI 230045
SVRPHI
NJC019-035-041-PAC011-017-025-029-077-089-091-095-230145-
/O.NEW.KPHI.SV.W.0183.170823T0045Z-170823T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
845 PM EDT TUE AUG 22 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Hunterdon County in northwestern New Jersey...
  Southwestern Warren County in northwestern New Jersey...
  Northwestern Somerset County in northern New Jersey...
  Berks County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Lehigh County in eastern Pennsylvania...
  Southeastern Carbon County in northeastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...
  Northeastern Chester County in southeastern Pennsylvania...
  South central Monroe County in northeastern Pennsylvania...
  Northampton County in eastern Pennsylvania...

* Until 945 PM EDT

* At 845 PM EDT, severe thunderstorms were located along a line
  extending from Kunkletown to near Spring Ridge, moving east at 55
  mph.

  HAZARD...Golf ball size hail and 70 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           considerable tree damage. Wind damage is also likely to 
           mobile homes, roofs, and outbuildings. 

* Locations impacted include...
  Allentown, Reading, Easton, Bethlehem, Norristown, Pottstown,
  Phoenixville, Lansdale, West Norriton, Forks, East Norriton,
  Emmaus, Wyomissing, Northampton, Quakertown, Perkasie, Doylestown,
  Byram, Wilson and Souderton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4089 7549 4069 7460 4006 7537 4035 7619
TIME...MOT...LOC 0045Z 270DEG 47KT 4085 7543 4036 7603 

TORNADO...POSSIBLE
HAIL...1.75IN
WIND...70MPH
 
$$

MWG

3 follow-up statements

090 
WWUS51 KPHI 230058
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
858 PM EDT TUE AUG 22 2017

NJC019-035-041-PAC011-017-025-029-077-089-091-095-230145-
/O.CON.KPHI.SV.W.0183.000000T0000Z-170823T0145Z/
Hunterdon NJ-Warren NJ-Somerset NJ-Berks PA-Montgomery PA-Lehigh PA-
Carbon PA-Bucks PA-Chester PA-Monroe PA-Northampton PA-
858 PM EDT TUE AUG 22 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR HUNTERDON...SOUTHWESTERN WARREN...NORTHWESTERN SOMERSET...EASTERN
BERKS...MONTGOMERY...LEHIGH...EASTERN CARBON...NORTHWESTERN BUCKS...
NORTHEASTERN CHESTER...SOUTH CENTRAL MONROE AND NORTHAMPTON
COUNTIES...

At 856 PM EDT, severe thunderstorms were located along a line
extending from Pen Argyl to near Laureldale, moving east at 55 mph.

HAZARD...70 mph wind gusts and ping pong ball size hail. 

SOURCE...Radar indicated. A report from social media showed dime 
         size hail in Kutztown. 

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect 
         considerable tree damage. Wind damage is also likely to 
         mobile homes, roofs, and outbuildings. 

Locations impacted include...
Allentown, Reading, Easton, Bethlehem, Norristown, Pottstown,
Phoenixville, Lansdale, West Norriton, Forks, East Norriton, Emmaus,
Wyomissing, Northampton, Quakertown, Perkasie, Doylestown, Byram,
Wilson and Souderton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4088 7546 4069 7460 4006 7537 4036 7606
TIME...MOT...LOC 0056Z 270DEG 47KT 4085 7526 4036 7586 

TORNADO...POSSIBLE
HAIL...1.50IN
WIND...70MPH
 
$$

MWG

185 
WWUS51 KPHI 230112
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
912 PM EDT TUE AUG 22 2017

PAC025-089-230122-
/O.CAN.KPHI.SV.W.0183.000000T0000Z-170823T0145Z/
Carbon PA-Monroe PA-
912 PM EDT TUE AUG 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN CARBON AND SOUTH
CENTRAL MONROE COUNTIES 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 midnight EDT for
northwestern New Jersey...and eastern and southeastern Pennsylvania.

LAT...LON 4084 7530 4069 7460 4006 7537 4032 7597
TIME...MOT...LOC 0112Z 270DEG 47KT 4085 7503 4036 7563 

$$

NJC019-035-041-PAC011-017-029-077-091-095-230145-
/O.CON.KPHI.SV.W.0183.000000T0000Z-170823T0145Z/
Hunterdon NJ-Warren NJ-Somerset NJ-Berks PA-Montgomery PA-Lehigh PA-
Bucks PA-Chester PA-Northampton PA-
912 PM EDT TUE AUG 22 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR HUNTERDON...SOUTHWESTERN WARREN...NORTHWESTERN SOMERSET...
SOUTHEASTERN BERKS...MONTGOMERY...SOUTHEASTERN LEHIGH...NORTHWESTERN
BUCKS...NORTHEASTERN CHESTER AND SOUTHERN NORTHAMPTON COUNTIES...

At 912 PM EDT, severe thunderstorms were located along a line
extending from near Belvidere to Bechtelsville, moving east at 55
mph.

HAZARD...70 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Minor damage to vehicles is possible. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings. 

Locations impacted include...
Allentown, Reading, Easton, Bethlehem, Norristown, Pottstown,
Phoenixville, Lansdale, West Norriton, Forks, East Norriton, Emmaus,
Wyomissing, Northampton, Quakertown, Perkasie, Doylestown, Byram,
Wilson and Souderton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4084 7530 4069 7460 4006 7537 4032 7597
TIME...MOT...LOC 0112Z 270DEG 47KT 4085 7503 4036 7563 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

MWG

303 
WWUS51 KPHI 230134
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
934 PM EDT TUE AUG 22 2017

NJC019-035-041-PAC011-017-029-077-091-095-230145-
/O.CON.KPHI.SV.W.0183.000000T0000Z-170823T0145Z/
Hunterdon NJ-Warren NJ-Somerset NJ-Berks PA-Montgomery PA-Lehigh PA-
Bucks PA-Chester PA-Northampton PA-
934 PM EDT TUE AUG 22 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR HUNTERDON...SOUTHWESTERN WARREN...NORTHWESTERN SOMERSET...
SOUTHEASTERN BERKS...MONTGOMERY...SOUTHEASTERN LEHIGH...NORTHWESTERN
BUCKS...NORTHEASTERN CHESTER AND SOUTHEASTERN NORTHAMPTON COUNTIES...

At 933 PM EDT, severe thunderstorms were located along a line
extending from Washington to Ottsville to near Bally, moving east at 
50 mph. Trees have been reported down in several locations in 
Northampton County.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated. 

IMPACT...Minor damage to vehicles is possible. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings. 

Locations impacted include...
Reading, Easton, Bethlehem, Norristown, Pottstown, Phoenixville,
Lansdale, West Norriton, East Norriton, Wyomissing, Quakertown,
Perkasie, Doylestown, Byram, Wilson, Souderton, Bedminster,
Washington, Hellertown and Birdsboro.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4069 7460 4006 7537 4032 7597 4052 7545
      4080 7510
TIME...MOT...LOC 0133Z 270DEG 43KT 4075 7497 4046 7515 4036 7557 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

CMS

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
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, 8:58 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, 10:07 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Delaware, Montgomery, Philadelphia	53 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 22, 10:40 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
Aug 22, 10:58 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	62 min
Aug 22, 11:46 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	44 min
Aug 23, 12:06 AM EDT	Flash Flood Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	4 hr
Aug 23, 12:29 AM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	46 min
Aug 23, 4:02 AM EDT	Areal Flood Warning	PHI	Chester, Delaware, Philadelphia	4 hr
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, 1:56 AM EDT	Areal Flood Advisory	PHI	Salem	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, 2017 Severe Thunderstorm Warnings in New Jersey, 2017 Every 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.