Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 253, NWS Philadelphia/Mount Holly

July 21, 20194 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2019, 11:05 PM EDT for 4 counties in Pennsylvania. It was in force for 40 min. 9 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 21, 2019, 11:05 PM EDT (03:05 UTC)
Expired: Jul 21, 2019, 11:45 PM EDT
In force: 40 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, Lehigh County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 105 km from the middle of the area, began a volume at 03:06 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 21, 11:06 PM EDT	TSTM WND DMG	1 N Lyons, PA	DOWNED TREE ON BASTIAN ROAD IN MAXATAWNY TWP. TIME ESTIMATED FROM RADAR.
Jul 21, 11:15 PM EDT	TSTM WND DMG	2 Ssw Alburtis, PA	DOWNED TREE NEAR THE INTERSECTION OF STATE STREET AND DOE MOUNTAIN LANE. TIME ESTIMATED FROM RADAR.
Jul 21, 11:16 PM EDT	TSTM WND DMG	2 Wsw Lower Frederick T, PA	A FOUR-FOOT DIAMETER TREE WAS BLOWN DOWN ACROSS GERLOFF ROAD NEAR RYANFORD ROAD. TIME ESTIMATED FROM RADAR.
Jul 21, 11:19 PM EDT	TSTM WND DMG	1 N Huffs Church, PA	DOWNED TREE ON HUNTER FORGE ROAD. TIME ESTIMATED FROM RADAR.
Jul 21, 11:19 PM EDT	TSTM WND DMG	1 Sse Alburtis, PA	REPORTS OF DOWNED TREES AND POWER LINES ON CHESTNUT ROAD. TIME ESTIMATED FROM RADAR.
Jul 21, 11:19 PM EDT	TSTM WND DMG	1 Ssw Zionsville, PA	DOWNED TREES AND WIRES ON CARLS HILL ROAD. TIME ESTIMATED FROM RADAR.
Jul 21, 11:22 PM EDT	TSTM WND DMG	1 Ene Huffs Church, PA	DOWNED TREES AND WIRES ON MULBERRY HILL ROAD. TIME ESTIMATED FROM RADAR.
Jul 21, 11:22 PM EDT	TSTM WND DMG	1 Sse Vera Cruz, PA	DOWNED TREE ON VERA CRUZ ROAD. ANOTHER DOWNED TREE REPORTED ON ROUTE 29. TIME ESTIMATED FROM RADAR.
Jul 21, 11:27 PM EDT	TSTM WND DMG	1 Wnw Vera Cruz, PA	EMERGENCY MANAGEMENT REPORTS 4-5 LARGE TREES DOWN. SOME OF THE TREES STRUCK A HOME CAUSING CONSIDERABLE STRUCTURAL DAMAGE MAKING IT UNINHABITABLE. TIME ESTIMATED FROM RADAR.

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 00:00Z, 3.1 hours before the alert went out and 225 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: 2295 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 1588 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 80 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

As transmitted.

121 
WUUS51 KPHI 220305
SVRPHI
PAC011-017-077-091-220345-
/O.NEW.KPHI.SV.W.0253.190722T0305Z-190722T0345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1105 PM EDT Sun Jul 21 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern Berks County in eastern Pennsylvania...
  Montgomery County in southeastern Pennsylvania...
  Lehigh County in eastern Pennsylvania...
  Northwestern Bucks County in southeastern Pennsylvania...

* Until 1145 PM EDT.

* At 1105 PM EDT, severe thunderstorms were located along a line
  extending from Kutztown to near Schwenksville, moving east at 30
  mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Allentown, Bethlehem, Norristown, Pottstown, Phoenixville,
  Lansdale, West Norriton, East Norriton, Emmaus, Northampton,
  Quakertown, Perkasie, Doylestown, Souderton, Bedminster, Ambler,
  Collegeville, Kutztown, Royersford and Hamburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with these storms. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4070 7551 4066 7548 4067 7543 4066 7542
      4063 7538 4058 7541 4054 7533 4056 7530
      4026 7498 4008 7533 4014 7551 4016 7550
      4016 7552 4024 7560 4024 7566 4052 7606
TIME...MOT...LOC 0305Z 251DEG 28KT 4050 7579 4025 7552 

HAIL...<.75IN
WIND...60MPH
 
$$

CMS

1 follow-up statement

010 
WWUS51 KPHI 220342
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1142 PM EDT Sun Jul 21 2019

PAC011-017-077-091-220351-
/O.EXP.KPHI.SV.W.0253.000000T0000Z-190722T0345Z/
Berks PA-Montgomery PA-Lehigh PA-Bucks PA-
1142 PM EDT Sun Jul 21 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BERKS...
MONTGOMERY...LEHIGH AND NORTHWESTERN BUCKS COUNTIES WILL EXPIRE AT
1145 PM EDT...

The storms which prompted the warning have moved out of the initial 
warning area and a new Severe Thunderstorm Warning has taken its 
place until 12:30 AM EDT.

LAT...LON 4070 7551 4066 7548 4067 7543 4066 7542
      4063 7538 4058 7541 4054 7533 4056 7530
      4026 7498 4008 7533 4014 7551 4016 7550
      4016 7552 4024 7560 4024 7566 4052 7606
TIME...MOT...LOC 0341Z 251DEG 28KT 4058 7547 4033 7520 

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 8:25 PM EDT	Special Weather Statement	PHI	Carbon, Lehigh, Northampton	50 min
Jul 21, 8:44 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	46 min
Jul 21, 9:24 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Northampton	51 min
Jul 21, 9:30 PM EDT	Severe Thunderstorm Warning	PHI	Chester	45 min
Jul 21, 9:58 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	2 hr
Jul 21, 10:14 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	46 min
Jul 21, 10:30 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh, Northampton	3 hr
Jul 21, 10:31 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh, Northampton	3 hr
Jul 21, 10:35 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	40 min
Jul 21, 10:42 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	48 min
Jul 21, 10:54 PM EDT	Severe Thunderstorm Warning	PHI	Delaware	25 min
Jul 21, 10:58 PM EDT	Areal Flood Advisory	PHI	Berks, Chester, Montgomery	59 min
Jul 21, 11:31 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	44 min
Jul 21, 11:38 PM EDT	Flash Flood Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	2 hr
Jul 21, 11:40 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Carbon, Lehigh, Montgomery, Northampton	50 min
Jul 22, 12:05 AM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	40 min
Jul 22, 12:45 AM EDT	Special Weather Statement	PHI	Monroe	30 min
Jul 22, 1:11 AM EDT	Special Weather Statement	PHI	Monroe	34 min
Jul 22, 5:32 AM EDT	Areal Flood Warning	PHI	Lehigh	49 min
Jul 22, 1:28 PM EDT	Special Weather Statement	PHI	Monroe	32 min
Jul 22, 1:50 PM EDT	Special Weather Statement	PHI	Northampton	25 min
Jul 22, 3:18 PM EDT	Special Weather Statement	PHI	Chester	57 min
Jul 22, 3:27 PM EDT	Severe Thunderstorm Warning	PHI	Monroe	48 min
Jul 22, 3:33 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe, Northampton	7 hr
Jul 22, 3:39 PM EDT	Special Weather Statement	PHI	Berks	51 min
Jul 22, 3:47 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	58 min
Jul 22, 4:11 PM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Lehigh, Montgomery, Northampton	4 hr
Jul 22, 4:16 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	59 min
Jul 22, 4:40 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	114 min
Jul 22, 4:55 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	50 min
Jul 22, 5:04 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	41 min
Jul 22, 5:05 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh, Northampton	4 hr
Jul 22, 5:14 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	61 min
Jul 22, 5:17 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	73 min
Jul 22, 5:34 PM EDT	Flash Flood Warning	PHI	Bucks, Lehigh, Montgomery, Northampton	4 hr
Jul 22, 5:40 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Philadelphia	80 min
Jul 22, 5:43 PM EDT	Areal Flood Advisory	PHI	Bucks	3 hr
Jul 22, 5:50 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	40 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Every severe thunderstorm warning in 2019

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.