Alert archive / Maryland / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 189, NWS Philadelphia/Mount Holly

August 21, 2016Caroline County, Maryland; Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 21, 2016, 5:06 PM EDT for Caroline County, Maryland; 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
Aug 21, 2016, 5:06 PM EDT (21:06 UTC)
Expired
Aug 21, 2016, 5:45 PM EDT
In force
39 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Kent County, DE, Caroline County, MD

The radar

The Dover AFB radar (KDOX), 28 km from the middle of the area, began a volume at 21:07 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 9.1 hours before the alert went out and 120 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 2016-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 110 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 2016-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 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
110 J/kg
Mixed-layer CIN
-40 J/kg
Mixed-layer LCL
859 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

291 
WUUS51 KPHI 212106
SVRPHI
DEC001-MDC011-212145-
/O.NEW.KPHI.SV.W.0189.160821T2106Z-160821T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
506 PM EDT SUN AUG 21 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN KENT COUNTY IN CENTRAL DELAWARE...
  EAST CENTRAL CAROLINE COUNTY IN EASTERN MARYLAND...

* UNTIL 545 PM EDT

* AT 505 PM EDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
  EXTENDING FROM NEAR RIDGELY TO NEAR GREENSBORO TO NEAR DENTON...
  MOVING NORTHEAST AT 35 MPH.

  HAZARD...60 MPH WIND GUSTS. 

  SOURCE...RADAR INDICATED. 

  IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES. 

* SEVERE THUNDERSTORMS WILL BE NEAR...
  HARRINGTON AROUND 520 PM EDT. 
  SANDTOWN AROUND 525 PM EDT. 
  VIOLA AROUND 530 PM EDT. 
  WOODSIDE AROUND 535 PM EDT. 
  CAMDEN AND RISING SUN-LEBANON AROUND 540 PM EDT. 

OTHER LOCATIONS IMPACTED BY THESE SEVERE THUNDERSTORMS INCLUDE
FELTON...RIVERVIEW...HOUSTON AND WOODSIDE EAST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

IN ADDITION TO DAMAGING WINDS...FREQUENT CLOUD TO GROUND LIGHTNING
IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

TORRENTIAL RAINFALL IS OCCURRING WITH THESE STORMS...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 3908 7569 3911 7553 3891 7548 3888 7577
      3890 7581 3892 7584
TIME...MOT...LOC 2105Z 226DEG 31KT 3892 7584 3892 7579 3889 7578 

HAIL...<.75IN
WIND...60MPH
 
$$

DRAG
2 follow-up statements
251 
WWUS51 KPHI 212122
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
522 PM EDT SUN AUG 21 2016

DEC001-MDC011-212145-
/O.CON.KPHI.SV.W.0189.000000T0000Z-160821T2145Z/
KENT DE-CAROLINE MD-
522 PM EDT SUN AUG 21 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM EDT
FOR SOUTHWESTERN KENT AND EAST CENTRAL CAROLINE COUNTIES...

AT 522 PM EDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
EXTENDING FROM NEAR VIOLA TO HARRINGTON...MOVING EAST AT 35 MPH.

HAZARD...60 MPH WIND GUSTS. 

SOURCE...RADAR INDICATED. 

IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES. 

THESE SEVERE THUNDERSTORMS WILL REMAIN OVER MAINLY RURAL AREAS OF
SOUTHWESTERN KENT AND EAST CENTRAL CAROLINE COUNTIES...INCLUDING THE
FOLLOWING LOCATIONS: FELTON...RIVERVIEW...HOUSTON AND WOODSIDE EAST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

IN ADDITION TO DAMAGING WINDS...FREQUENT CLOUD TO GROUND LIGHTNING
IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

TORRENTIAL RAINFALL IS OCCURRING WITH THESE STORMS...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 3901 7575 3907 7552 3891 7548 3888 7577
      3890 7581 3892 7584
TIME...MOT...LOC 2122Z 268DEG 29KT 3901 7557 3897 7558 3891 7557 

HAIL...<.75IN
WIND...60MPH
 
$$

DRAG
922 
WWUS51 KPHI 212136
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
536 PM EDT SUN AUG 21 2016

DEC001-MDC011-212145-
/O.EXP.KPHI.SV.W.0189.000000T0000Z-160821T2145Z/
KENT DE-CAROLINE MD-
536 PM EDT SUN AUG 21 2016

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN KENT AND EAST
CENTRAL CAROLINE COUNTIES WILL EXPIRE AT 545 PM EDT...
    
THE STORMS WHICH PROMPTED THE WARNING HAVE MOVED OUT OF THE AREA.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.  HOWEVER HEAVY RAIN
IS STILL POSSIBLE WITH THESE THUNDERSTORMS.

LAT...LON 3901 7575 3907 7552 3891 7548 3888 7577
      3890 7581 3892 7584
TIME...MOT...LOC 2133Z 226DEG 31KT 3901 7557 3897 7558 3891 7557 

$$

DRAG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 2:38 PM EDTSpecial Weather StatementPHICecil22 min
Aug 21, 2:51 PM EDTAreal Flood AdvisoryPHICecil114 min
Aug 21, 2:57 PM EDTSpecial Weather StatementPHIKent, Queen Anne's33 min
Aug 21, 3:30 PM EDTAreal Flood AdvisoryPHICaroline, Cecil, Kent, Queen Anne's2 hr
Aug 21, 3:40 PM EDTSpecial Weather StatementPHITalbot50 min
Aug 21, 3:50 PM EDTSpecial Weather StatementPHIKent25 min
Aug 21, 4:06 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's39 min
Aug 21, 4:19 PM EDTSpecial Weather StatementPHITalbot26 min
Aug 21, 4:20 PM EDTFlash Flood WarningPHICecil, Kent, Queen Anne's4 hr
Aug 21, 4:29 PM EDTSpecial Weather StatementPHICaroline31 min
Aug 21, 4:50 PM EDTAreal Flood AdvisoryPHICaroline, Queen Anne's, Talbot3 hr
Aug 21, 4:54 PM EDTSpecial Weather StatementPHICaroline36 min
Aug 21, 5:09 PM EDTFlash Flood WarningPHICaroline, Queen Anne's, Talbot4 hr
Aug 21, 6:35 PM EDTAreal Flood AdvisoryPHICaroline, Queen Anne's, Talbot3 hr
Aug 21, 3:47 PM EDTAreal Flood AdvisoryPHINew Castle118 min
Aug 21, 5:28 PM EDTSpecial Weather StatementPHIKent17 min
Aug 21, 5:46 PM EDTSpecial Weather StatementPHISussex14 min
Aug 21, 5:54 PM EDTSpecial Weather StatementPHISussex36 min
Aug 21, 6:31 PM EDTSpecial Weather StatementPHISussex29 min
Aug 21, 7:04 PM EDTSpecial Weather StatementPHISussex26 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2016Severe Thunderstorm Warnings in Delaware, 2016Every severe thunderstorm warning in 2016

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.