Alert archive / Delaware / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 63, NWS Philadelphia/Mount Holly

June 9, 2009Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2009, 6:57 PM EDT for Kent County, Delaware. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 9, 2009, 6:57 PM EDT (22:57 UTC)
Expired: Jun 9, 2009, 7:36 PM EDT
In force: 39 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Kent County, DE

The radar

The Dover AFB radar (KDOX), 24 km from the middle of the area, began a volume at 23:00 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.

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 11.0 hours before the alert went out and 69 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: 1272 J/kg
Mixed-layer CIN: -67 J/kg
Mixed-layer LCL: 804 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 092257
SVRPHI
DEC001-100000-
/O.NEW.KPHI.SV.W.0063.090609T2257Z-090610T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
657 PM EDT TUE JUN 9 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  KENT COUNTY IN CENTRAL DELAWARE...
  THIS INCLUDES THE CITY OF DOVER...

* UNTIL 800 PM EDT

* AT 657 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR HAZLETTVILLE...OR 7 MILES WEST OF DOVER...
  AND MOVING SOUTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  6 MILES SOUTHWEST OF DOVER AND 7 MILES SOUTHWEST OF DOVER SPEEDWAY
  AROUND 710 PM EDT...
  CAMDEN AROUND 715 PM EDT...
  WOODSIDE...VIOLA AND RISING SUN AROUND 720 PM EDT...
  9 MILES NORTHEAST OF HARRINGTON AROUND 740 PM EDT...
  BOWERS AROUND 745 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
TUESDAY EVENING FOR NORTHEASTERN PENNSYLVANIA.

&&

LAT...LON 3884 7571 3897 7574 3924 7575 3925 7542
      3916 7540 3907 7539 3906 7536 3899 7534
      3885 7557
TIME...MOT...LOC 2257Z 307DEG 15KT 3913 7565

$$

NIERENBERG

1 follow-up statement

000 
WWUS51 KPHI 092336
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
736 PM EDT TUE JUN 9 2009

DEC001-092345-
/O.CAN.KPHI.SV.W.0063.000000T0000Z-090610T0000Z/
KENT DE-
736 PM EDT TUE JUN 9 2009

...THE SEVERE THUNDERSTORM WARNING FOR KENT COUNTY IS CANCELLED...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS MOVED OUT OF KENT 
COUNTY.

LAT...LON 3884 7571 3897 7574 3924 7575 3925 7542
      3916 7540 3907 7539 3906 7536 3899 7534
      3885 7557
TIME...MOT...LOC 2335Z 307DEG 15KT 3903 7549

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 8:20 AM EDT	Areal Flood Advisory	PHI	New Castle	3 hr
Jun 9, 8:31 AM EDT	Severe Thunderstorm Warning	PHI	Sussex	59 min
Jun 9, 9:09 AM EDT	Areal Flood Advisory	PHI	Kent, Sussex	3 hr
Jun 9, 1:49 PM EDT	Flash Flood Watch	PHI	New Castle	5 hr
Jun 9, 4:19 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	56 min
Jun 9, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	92 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2009 Every severe thunderstorm warning in 2009

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.