Alert archive / Maryland / Severe Thunderstorm Warnings in 2010

Severe Thunderstorm Warning 124, NWS Philadelphia/Mount Holly

July 29, 2010Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 29, 2010, 2:53 PM EDT for Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Sussex County, Delaware. It was in force for 41 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 29, 2010, 2:53 PM EDT (18:53 UTC)
Expired
Jul 29, 2010, 3:34 PM EDT
In force
41 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The radar

The Dover AFB radar (KDOX), 12 km from the middle of the area, began a volume at 18:55 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.

IssuedProductOfficeLasted
Jul 29, 11:54 AM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 6.9 hours before the alert went out and 89 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-pSkew-T log-p diagram, Wallops Is Stn, VA at 12:00Z on 2010-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1121 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 2010-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1121 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
948 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
98 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.

019 
WUUS51 KPHI 291853
SVRPHI
DEC001-005-MDC011-035-041-292030-
/O.NEW.KPHI.SV.W.0124.100729T1853Z-100729T2030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
253 PM EDT THU JUL 29 2010

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN KENT COUNTY IN CENTRAL DELAWARE...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTHEASTERN TALBOT COUNTY IN EASTERN MARYLAND...
  CENTRAL QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...
  SUSSEX COUNTY IN SOUTHERN DELAWARE...
  THIS INCLUDES THE CITY OF GEORGETOWN...

* UNTIL 430 PM EDT

* AT 251 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR JUMPTOWN...OR 9
  MILES SOUTHEAST OF CENTERVILLE...AND MOVING EAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  GREENSBORO AND DENTON AROUND 305 PM EDT...
  ANDREWSVILLE AROUND 320 PM EDT...
  HARRINGTON AROUND 325 PM EDT...
  MILFORD AROUND 340 PM EDT...
  SLAUGHTER BEACH AROUND 350 PM EDT...
  SLAUGHTER BEACH AROUND 355 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES GREATEST KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

&&

LAT...LON 3849 7547 3865 7572 3875 7584 3890 7609
      3913 7594 3899 7531 3893 7530 3883 7521
      3879 7513 3881 7509 3880 7507 3846 7503
      3844 7505 3844 7516
TIME...MOT...LOC 1853Z 279DEG 29KT 3897 7591

$$

NIERENBERG
2 follow-up statements
370 
WWUS51 KPHI 291926
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
326 PM EDT THU JUL 29 2010

MDC035-041-291936-
/O.CAN.KPHI.SV.W.0124.000000T0000Z-100729T2030Z/
QUEEN ANNE'S MD-TALBOT MD-
326 PM EDT THU JUL 29 2010

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN TALBOT AND
CENTRAL QUEEN ANNE'S COUNTIES IS CANCELLED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

LAT...LON 3849 7547 3865 7572 3867 7574 3868 7575
      3875 7584 3894 7573 3895 7531 3893 7530
      3883 7521 3879 7513 3881 7509 3880 7507
      3846 7503 3844 7505 3844 7516
TIME...MOT...LOC 1926Z 279DEG 29KT 3893 7557

$$

DEC001-005-MDC011-292030-
/O.CON.KPHI.SV.W.0124.000000T0000Z-100729T2030Z/
KENT DE-CAROLINE MD-SUSSEX DE-
326 PM EDT THU JUL 29 2010

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM EDT
FOR SUSSEX...SOUTHEASTERN CAROLINE AND SOUTHERN KENT COUNTIES...

AT 325 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR
HARRINGTON...OR 16 MILES SOUTH OF DOVER...MOVING EAST AT 35 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  HOUSTON BY 335 PM EDT...
  MILFORD BY 340 PM EDT...
  7 MILES NORTH OF ELLENDALE BY 345 PM EDT...
  SLAUGHTER BEACH BY 350 PM EDT...
  8 MILES NORTH OF MILTON BY 355 PM EDT...
  6 MILES NORTH OF LEWES BY 410 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

&&

LAT...LON 3849 7547 3865 7572 3867 7574 3868 7575
      3875 7584 3894 7573 3895 7531 3893 7530
      3883 7521 3879 7513 3881 7509 3880 7507
      3846 7503 3844 7505 3844 7516
TIME...MOT...LOC 1926Z 279DEG 29KT 3893 7557

$$

NIERENBERG
934 
WWUS51 KPHI 291934
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
334 PM EDT THU JUL 29 2010

DEC001-005-MDC011-291944-
/O.CAN.KPHI.SV.W.0124.000000T0000Z-100729T2030Z/
KENT DE-CAROLINE MD-SUSSEX DE-
334 PM EDT THU JUL 29 2010

...THE SEVERE THUNDERSTORM WARNING FOR SUSSEX...SOUTHEASTERN CAROLINE
AND SOUTHERN KENT COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO LONGER 
SEVERE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM EDT
THURSDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN
NEW JERSEY.

LAT...LON 3849 7547 3865 7572 3867 7574 3868 7575
      3875 7584 3894 7573 3895 7531 3893 7530
      3883 7521 3879 7513 3881 7509 3880 7507
      3846 7503 3844 7505 3844 7516
TIME...MOT...LOC 1934Z 279DEG 29KT 3892 7549

$$

NIERENBERG

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 1:25 PM EDTSpecial Weather StatementPHICaroline, Kent, Queen Anne's, Talbot95 min
Jul 29, 1:50 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot85 min
Jul 29, 1:20 PM EDTSpecial Weather StatementPHISussex55 min
Jul 29, 1:39 PM EDTSevere Thunderstorm WarningPHISussex34 min
Jul 29, 2:28 PM EDTSpecial Weather StatementPHIKent, New Castle, Sussex92 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2010Severe Thunderstorm Warnings in Delaware, 2010Every severe thunderstorm warning in 2010

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.