Alert archive / Delaware / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 60, NWS Philadelphia/Mount Holly

May 19, 2011Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 19, 2011, 5:46 PM EDT for Kent County, Delaware. It was in force for 30 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: May 19, 2011, 5:46 PM EDT (21:46 UTC)
Expired: May 19, 2011, 6:16 PM EDT
In force: 30 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Kent County, DE

The radar

The Dover AFB radar (KDOX), 44 km from the middle of the area, began a volume at 21:46 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, 9.8 hours before the alert went out and 62 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: 143 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 819 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: -13 m²/s²
0-3 km storm-relative helicity: 53 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

348 
WUUS51 KPHI 192146
SVRPHI
DEC001-192245-
/O.NEW.KPHI.SV.W.0060.110519T2146Z-110519T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
546 PM EDT THU MAY 19 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN KENT COUNTY IN CENTRAL DELAWARE...

* UNTIL 645 PM EDT

* AT 542 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR LITTLE CREEK...OR NEAR DOVER...AND MOVING
  NORTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  RURAL NORTHEASTERN KENT COUNTY AT 600 PM EDT

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...HEAVY RAIN WILL OCCUR
WITH THESE STORMS AND CAUSE LOW-LYING AND POOR DRAINAGE FLOODING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3924 7559 3933 7544 3932 7543 3924 7538
      3920 7538 3916 7540 3913 7540 3912 7544
TIME...MOT...LOC 2146Z 224DEG 11KT 3922 7545

$$

PO

1 follow-up statement

026 
WWUS51 KPHI 192216 RRA
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
616 PM EDT THU MAY 19 2011

DEC001-192227-
/O.CAN.KPHI.SV.W.0060.000000T0000Z-110519T2245Z/
KENT DE-
616 PM EDT THU MAY 19 2011

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

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
THURSDAY EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 3924 7559 3933 7544 3932 7543 3924 7538
      3920 7538 3916 7540 3913 7540 3912 7544
TIME...MOT...LOC 2217Z 224DEG 11KT 3929 7536

$$

PO

The office that day

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

Issued	Product	Office	Counties	Lasted
May 19, 1:00 PM EDT	Special Weather Statement	PHI	Kent	60 min
May 19, 1:37 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	6 hr
May 19, 1:44 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	46 min
May 19, 2:19 PM EDT	Special Weather Statement	PHI	New Castle	56 min
May 19, 3:01 PM EDT	Areal Flood Advisory	PHI	New Castle	3 hr
May 19, 3:52 PM EDT	Coastal Flood Statement	PHI	Kent, New Castle, Sussex	8 hr
May 19, 5:11 PM EDT	Severe Thunderstorm Warning	PHI	Kent	34 min
May 19, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	62 min
May 19, 5:16 PM EDT	Severe Thunderstorm Warning	PHI	Kent	29 min
May 19, 5:23 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	53 min
May 19, 6:12 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	18 min
May 19, 6:53 PM EDT	Special Weather Statement	PHI	Sussex	67 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2011 Every severe thunderstorm warning in 2011

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.