Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 11, NWS Philadelphia/Mount Holly

March 8, 2008Delaware County, Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Mar 8, 2008, 5:22 PM EST for Delaware County, Pennsylvania; New Castle County, Delaware. It was in force for 23 min. 1 report 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: Mar 8, 2008, 5:22 PM EST (22:22 UTC)
Expired: Mar 8, 2008, 5:45 PM EST
In force: 23 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties New Castle County, DE, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 96 km from the middle of the area, began a volume at 22:22 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
Mar 8, 5:30 PM EST	TSTM WND DMG	Wilmington, DE	NUMEROUS REPORTS OF TREES, POLES AND WIRES DOWN IN THE NORTHERN PART OF THE COUNTY.

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 12:00Z, 10.4 hours before the alert went out and 186 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 459 m above ground
0-6 km bulk shear: 90 kt
0-1 km storm-relative helicity: 495 m²/s²
0-3 km storm-relative helicity: 578 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS51 KPHI 082222
SVRPHI
DEC003-PAC045-082245-
/O.NEW.KPHI.SV.W.0011.080308T2222Z-080308T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
522 PM EST SAT MAR 8 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF SPRINGFIELD...

* UNTIL 545 PM EST

* AT 518 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN
  EXCESS OF 65 MPH.  THIS STORM WAS LOCATED NEAR BEAR...OR ABOUT NEAR
  NEWARK...AND MOVING NORTHEAST AT 60 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  LIMA...CHELSEA...ELAM AND CONCORDVILLE BY 530 PM EST...
  NEWTOWN SQUARE...TROUT LAKE...BROOMALL AND NETHER PROVIDENCE
  TOWNSHIP BY 535 PM EST...

LAT...LON 4003 7537 3998 7528 3996 7527 3980 7542
      3979 7541 3976 7547 3972 7547 3965 7556
      3965 7559 3960 7560 3960 7557 3957 7560
      3964 7579 3966 7579
TIME...MOT...LOC 2222Z 213DEG 82KT 3972 7561

$$

SZATKOWSKI

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 8, 4:40 AM EST	Wind Advisory	PHI	Berks, Carbon, Delaware, Lehigh, Monroe, Northampton and 1 more	27 hr
Mar 8, 12:03 PM EST	Flash Flood Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
Mar 8, 1:05 PM EST	River Flood Warning	PHI	Bucks	13 hr
Mar 8, 3:58 PM EST	High Wind Warning	PHI	Berks, Carbon, Delaware, Lehigh, Monroe, Northampton and 1 more	6 hr
Mar 8, 5:44 PM EST	Severe Thunderstorm Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	46 min
Mar 8, 5:49 PM EST	Severe Thunderstorm Warning	PHI	Carbon, Lehigh, Monroe, Northampton	41 min
Mar 8, 2:40 PM EST	Severe Thunderstorm Warning	PHI	Sussex	37 min
Mar 8, 2:50 PM EST	River Flood Warning	PHI	New Castle	3 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2008 Severe Thunderstorm Warnings in Delaware, 2008 Every severe thunderstorm warning in 2008

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.