Alert archive / Maryland / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 98, NWS Philadelphia/Mount Holly

July 9, 20154 counties in Maryland; Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 9, 2015, 8:23 PM EDT for 4 counties in Maryland; Kent County, New Castle County, Delaware. It was in force for 22 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: Jul 9, 2015, 8:23 PM EDT (00:23 UTC)
Expired: Jul 9, 2015, 8:45 PM EDT
In force: 22 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Kent County, DE, New Castle County, DE, Caroline County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 43 km from the middle of the area, began a volume at 00:26 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 9, 4:57 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.4 hours before the alert went out and 124 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: 809 J/kg
Mixed-layer CIN: -68 J/kg
Mixed-layer LCL: 1310 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 127 m²/s²
0-3 km storm-relative helicity: 192 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.2

Open this sounding in Storm Lab

The text

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

664 
WUUS51 KPHI 100023
SVRPHI
DEC001-003-MDC011-029-035-041-100045-
/O.NEW.KPHI.SV.W.0098.150710T0023Z-150710T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
823 PM EDT THU JUL 9 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  NORTHWESTERN KENT COUNTY IN CENTRAL DELAWARE...
  EASTERN QUEEN ANNE'S COUNTY IN NORTHEASTERN MARYLAND...
  NORTHERN CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTHERN TALBOT COUNTY IN EASTERN MARYLAND...
  EAST CENTRAL KENT COUNTY IN NORTHEASTERN MARYLAND...

* UNTIL 845 PM EDT

* AT 822 PM EDT...DOPPLER RADAR INDICATED A LINE OF SEVERE
  THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN EXCESS OF
  70 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 6
  MILES NORTHEAST OF DOVER BASE HOUSING TO WOODSIDE TO NEAR
  GRIFFIN...AND MOVING EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  EASTON...SMYRNA...DENTON...CLAYTON...GREENSBORO...OAKLAND...
  RIDGELY...CHESWOLD...GOLDSBORO...QUEEN ANNE...HARTLY...STARR...
  DELANEY CORNER...CORDOVA...HAZLETTVILLE...JUMPTOWN...SKIPTON...
  SANDTOWN...GRIFFIN AND MATTHEWS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DEADLY LIGHTNING AND 
VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON 
THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS 
QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3890 7608 3931 7574 3931 7549 3886 7582
      3876 7596 3881 7611
TIME...MOT...LOC 0022Z 267DEG 43KT 3918 7540 3907 7556 3883 7589 

$$

GORSE/FRANCK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 9, 8:15 PM EDT	Severe Thunderstorm Warning	PHI	Caroline	45 min
Jul 9, 9:01 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	44 min
Jul 9, 9:45 PM EDT	Special Weather Statement	PHI	Sussex	30 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2015 Severe Thunderstorm Warnings in Delaware, 2015 Every severe thunderstorm warning in 2015

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.