Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 224, NWS Philadelphia/Mount Holly

July 17, 2019New Castle County, Delaware; Chester County, Delaware County, Pennsylvania; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2019, 6:35 PM EDT for New Castle County, Delaware; Chester County, Delaware County, Pennsylvania; Cecil County, Maryland. It was in force for 40 min. 5 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 17, 2019, 6:35 PM EDT (22:35 UTC)
Expired: Jul 17, 2019, 7:15 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 New Castle County, DE, Cecil County, MD, Chester County, PA, Delaware County, PA

The radar

The Dover AFB radar (KDOX), 112 km from the middle of the area, began a volume at 22:38 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 17, 7:00 PM EDT	TSTM WND DMG	Rising Sun, MD	NUMEROUS TREES DOWN IN RISING SUN. TIME ESTIMATED FROM RADAR.
Jul 17, 7:03 PM EDT	TSTM WND DMG	1 Wsw Port Deposit, MD	DOWNED UTILITY ON MD-276 BOTH DIRECTIONS AT MD-222. ROAD CLOSED. TIME ESTIMATED FROM RADAR.
Jul 17, 7:15 PM EDT	TSTM WND DMG	2 Wnw Brandamore, PA	POLES AND WIRES DOWN ON BIRDELL RD AT GOOSEBERRY LN. TIME ESTIMATED FROM RADAR.
Jul 17, 7:17 PM EDT	TSTM WND DMG	1 E Parkesburg, PA	REPORT OF POWER POLES AND WIRES BLOWN DOWN ONTO CARS NEAR TIMACULA RD AT ROUTE 372. TIME ESTIMATED FROM RADAR.
Jul 17, 7:20 PM EDT	TSTM WND DMG	1 Nnw Caln Twp, PA	POLES AND WIRES DOWN ON FISHERVILLE RD AT N BAILEY RD. 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
Jul 17, 4:51 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 17, 1:58 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.6 hours before the alert went out and 160 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: 237 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 1666 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 67 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

555 
WUUS51 KPHI 172235
SVRPHI
DEC003-MDC015-PAC029-045-172315-
/O.NEW.KPHI.SV.W.0224.190717T2235Z-190717T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
635 PM EDT Wed Jul 17 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern New Castle County in northern Delaware...
  Cecil County in northeastern Maryland...
  Chester County in southeastern Pennsylvania...
  Southwestern Delaware County in southeastern Pennsylvania...

* Until 715 PM EDT.

* At 634 PM EDT, severe thunderstorms were located along a line
  extending from Millersville to near Havre De Grace, moving
  northeast at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Wilmington, Newark, West Chester, Elkton, Calvert, Coatesville,
  Westtown, Carneys Point, Downingtown, Elsmere, Kennett Square, New
  Castle, Penns Grove, Oxford, Parkesburg, North East, West Grove,
  Rising Sun, Honey Brook and Elverson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3973 7610 3976 7606 3983 7604 3987 7599
      3995 7600 4004 7593 4011 7594 4024 7569
      3979 7541 3977 7546 3971 7548 3972 7552
      3966 7556 3945 7601 3952 7598 3955 7603
      3955 7608 3972 7623
TIME...MOT...LOC 2234Z 238DEG 37KT 3999 7635 3952 7605 

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

Fitzsimmons

1 follow-up statement

175 
WWUS51 KPHI 172300 RRA
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
700 PM EDT Wed Jul 17 2019

DEC003-MDC015-PAC029-045-172315-
/O.CON.KPHI.SV.W.0224.000000T0000Z-190717T2315Z/
New Castle DE-Cecil MD-Chester PA-Delaware PA-
700 PM EDT Wed Jul 17 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM EDT
FOR NORTHERN NEW CASTLE...CECIL...CHESTER AND SOUTHWESTERN DELAWARE
COUNTIES...

At 657 PM EDT, severe thunderstorms were located along a line 
extending from Bareville to near Elkton, moving northeast at 40 mph. 
Worth noting, there has also been some rotation detected with cells 
on a portion of this line over Lancaster County PA as it moves 
toward Chester County. 

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Wilmington, Newark, West Chester, Elkton, Calvert, Coatesville,
Westtown, Carneys Point, Downingtown, Elsmere, Kennett Square, New
Castle, Penns Grove, Oxford, Parkesburg, North East, West Grove,
Rising Sun, Honey Brook and Elverson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3973 7610 3976 7606 3983 7604 3987 7599
      3995 7600 4004 7593 4011 7594 4024 7569
      3979 7541 3977 7546 3971 7548 3972 7552
      3966 7556 3945 7601 3952 7598 3955 7603
      3955 7608 3972 7623
TIME...MOT...LOC 2257Z 237DEG 37KT 4010 7613 3963 7583 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...70MPH
 
$$

Fitzsimmons

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 3:54 AM EDT	Flash Flood Watch	PHI	New Castle	19 hr
Jul 17, 3:14 PM EDT	Excessive Heat Watch	PHI	Kent, Sussex	24 hr
Jul 17, 6:44 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	46 min
Jul 17, 7:15 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	45 min
Jul 17, 7:17 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	43 min
Jul 17, 7:44 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	46 min
Jul 16, 9:15 PM EDT	Special Weather Statement	PHI	Philadelphia	45 min
Jul 17, 1:26 PM EDT	Special Weather Statement	PHI	Pike	34 min
Jul 17, 1:50 PM EDT	Areal Flood Advisory	PHI	Carbon, Lehigh, Monroe, Northampton	80 min
Jul 17, 2:05 PM EDT	Special Weather Statement	PHI	Lehigh	25 min
Jul 17, 5:05 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	40 min
Jul 17, 5:14 PM EDT	Special Weather Statement	PHI	Lehigh	46 min
Jul 17, 5:44 PM EDT	Special Weather Statement	PHI	Monroe	46 min
Jul 17, 5:46 PM EDT	Areal Flood Advisory	PHI	Monroe	119 min
Jul 17, 5:49 PM EDT	Special Weather Statement	PHI	Lehigh, Northampton	41 min
Jul 17, 6:24 PM EDT	Special Weather Statement	PHI	Berks	51 min
Jul 17, 6:51 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	54 min
Jul 17, 6:52 PM EDT	Areal Flood Advisory	PHI	Berks	113 min
Jul 17, 7:06 PM EDT	Flash Flood Warning	PHI	Berks	3 hr
Jul 17, 7:21 PM EDT	Flash Flood Warning	PHI	Chester	97 min
Jul 17, 7:31 PM EDT	Special Weather Statement	PHI	Lehigh, Northampton	44 min
Jul 17, 7:36 PM EDT	Flash Flood Warning	PHI	Bucks, Lehigh, Montgomery	3 hr
Jul 17, 7:44 PM EDT	Special Weather Statement	PHI	Lehigh	31 min
Jul 17, 7:56 PM EDT	Special Weather Statement	PHI	Bucks, Montgomery, Philadelphia	64 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Severe Thunderstorm Warnings in Delaware, 2019 Severe Thunderstorm Warnings in Maryland, 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.