Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 156, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 5, 2017, 12:10 AM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 51 min. 2 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 5, 2017, 12:10 AM EDT (04:10 UTC)
- Expired
- Aug 5, 2017, 1:01 AM EDT
- In force
- 51 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Berks County, PA, Chester County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 123 km from the middle of the area, began a volume at 04:11 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 5, 1:07 AM EDT | TSTM WND DMG | Colebrookdale, PA | A FEW TREES DOWN IN WASHINGTON AND COLEBROOKDALE TOWNSHIPS. |
| Aug 5, 1:07 AM EDT | TSTM WND DMG | Washington Twp, PA | A TREE OR TWO DOWN IN WASHINGTON AND COLEBROOKDALE TOWNSHIPS. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 00:00Z, 4.2 hours before the alert went out and 185 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
- 786 J/kg
- Mixed-layer CIN
- -29 J/kg
- Mixed-layer LCL
- 1447 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 128 m²/s²
- 0-3 km storm-relative helicity
- 202 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 3.7
The text
As transmitted.
158
WUUS51 KPHI 050410
SVRPHI
PAC011-029-091-050515-
/O.NEW.KPHI.SV.W.0156.170805T0410Z-170805T0515Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1210 AM EDT SAT AUG 5 2017
The National Weather Service in Mount Holly NJ has issued a
* Severe Thunderstorm Warning for...
Southeastern Berks County in eastern Pennsylvania...
Northwestern Montgomery County in southeastern Pennsylvania...
Chester County in southeastern Pennsylvania...
* Until 115 AM EDT
* At 1209 AM EDT, severe thunderstorms were located along a line
extending from near Sinking Spring to Leola to near Quarryville,
moving northeast at 35 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to trees and power lines.
* Locations impacted include...
Reading, West Chester, Pottstown, Phoenixville, Coatesville,
Wyomissing, Downingtown, Kennett Square, Birdsboro, Collegeville,
Royersford, Sinking Spring, Parkesburg, Trappe, East Greenville,
West Grove, Honey Brook, Schwenksville, Elverson and Bally.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Prepare immediately for deadly cloud to ground lightning. Seek
shelter inside a well-built structure. Stay away from windows.
Torrential rainfall is occurring with these storms, and may lead to
flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4050 7562 4037 7540 4036 7539 3984 7562
3980 7604 3985 7602 3987 7599 3992 7600
3994 7598 3995 7600 4004 7593 4011 7594
4014 7588 4029 7611
TIME...MOT...LOC 0409Z 241DEG 32KT 4030 7605 4010 7618 3988 7622
HAIL...<.75IN
WIND...60MPH
$$
Gorse2 follow-up statements
555
WWUS51 KPHI 050434
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
1234 AM EDT SAT AUG 5 2017
PAC011-029-091-050515-
/O.CON.KPHI.SV.W.0156.000000T0000Z-170805T0515Z/
Berks PA-Montgomery PA-Chester PA-
1234 AM EDT SAT AUG 5 2017
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR SOUTHEASTERN BERKS...NORTHWESTERN MONTGOMERY AND CHESTER
COUNTIES...
At 1234 AM EDT, severe thunderstorms were located along a line
extending from near Adamstown to near New Morgan to near Honey Brook
to Gap, moving northeast at 40 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to trees and power lines.
Locations impacted include...
Reading, West Chester, Pottstown, Phoenixville, Coatesville,
Wyomissing, Downingtown, Kennett Square, Birdsboro, Collegeville,
Royersford, Sinking Spring, Parkesburg, Trappe, East Greenville, West
Grove, Honey Brook, Schwenksville, Elverson and Bally.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
Torrential rainfall is occurring with these storms, and may lead to
flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4050 7562 4037 7540 4036 7539 3984 7562
3980 7604 3985 7602 3987 7599 3992 7600
3994 7598 3995 7600 4004 7593 4011 7594
4014 7588 4029 7611
TIME...MOT...LOC 0434Z 242DEG 33KT 4028 7606 4020 7595 4006 7593 3998
7599
HAIL...<.75IN
WIND...60MPH
$$
Gorse796
WWUS51 KPHI 050501
SVSPHI
Severe Weather Statement
National Weather Service Mount Holly NJ
101 AM EDT SAT AUG 5 2017
PAC011-029-091-050510-
/O.CAN.KPHI.SV.W.0156.000000T0000Z-170805T0515Z/
Berks PA-Montgomery PA-Chester PA-
101 AM EDT SAT AUG 5 2017
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BERKS...
NORTHWESTERN MONTGOMERY AND CHESTER COUNTIES IS CANCELLED...
The storms which prompted the warning have weakened, and no longer
pose an immediate threat to life or property. Therefore the warning
has been cancelled. However heavy rain is occurring with these
thunderstorms.
LAT...LON 4050 7562 4037 7540 4036 7539 3984 7562
3980 7604 3985 7602 3987 7599 3992 7600
3994 7598 3995 7600 4004 7593 4011 7594
4014 7588 4029 7611
TIME...MOT...LOC 0500Z 241DEG 32KT 4039 7580 4031 7569 4017 7567 4009
7573
$$
GorseThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 4, 11:36 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 69 min |
| Aug 4, 11:49 PM EDT | Special Weather Statement | PHI | Carbon, Lehigh | 56 min |
| Aug 5, 1:42 AM EDT | Special Weather Statement | PHI | Bucks, Montgomery, Northampton | 48 min |
| Aug 5, 1:59 AM EDT | Special Weather Statement | PHI | Chester, Montgomery | 46 min |
| Aug 5, 2:38 AM EDT | Special Weather Statement | PHI | Chester | 52 min |
| Aug 5, 2:41 AM EDT | Special Weather Statement | PHI | Bucks, Montgomery, Philadelphia | 49 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 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.