Alert archive / Delaware / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 9, NWS Philadelphia/Mount Holly

May 16, 2007New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 16, 2007, 4:21 PM EDT for New Castle County, Delaware. It was in force for 39 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: May 16, 2007, 4:21 PM EDT (20:21 UTC)
Expired: May 16, 2007, 5:00 PM EDT
In force: 39 min
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

County New Castle County, DE

The radar

The Philadelphia radar (KDIX), 104 km from the middle of the area, began a volume at 20:24 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
May 16, 4:35 PM EDT	TSTM WND DMG	Hockessin, DE	WIRES REPORTED DOWN IN NORTHERN NEW CASTLE COUNTY.

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
May 16, 1:26 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 8.4 hours before the alert went out and 53 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: 18 J/kg
Mixed-layer CIN: -160 J/kg
Mixed-layer LCL: 1421 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 138 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 162021
SVRPHI
DEC003-162100-
/O.NEW.KPHI.SV.W.0009.070516T2021Z-070516T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
421 PM EDT WED MAY 16 2007

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...

* UNTIL 500 PM EDT

* AT 419 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES NORTHWEST OF NEWARK...
  AND MOVING EAST AT 50 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  NORTH STAR...PIKE CREEK AND HOCKESSIN BY 430 PM EDT...
  ELSMERE...STANTON...NEWPORT AND WILMINGTON MANOR BY 435 PM EDT...
  BELLEFONTE...WILMINGTON AND TALLEYVILLE BY 440 PM EDT...

LAT...LON 3983 7563 3975 7576 3959 7578 3959 7560
      3979 7544 3980 7546 3983 7550

$$

MPD

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 5:20 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	40 min
May 16, 5:41 PM EDT	Severe Thunderstorm Warning	PHI	Kent	79 min
May 16, 6:35 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	70 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2007 Every severe thunderstorm warning in 2007

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.