Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 115, NWS Philadelphia/Mount Holly

July 22, 2017Caroline County, Queen Anne's County, Talbot County, Maryland; Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 22, 2017, 3:38 PM EDT for Caroline County, Queen Anne's County, Talbot County, Maryland; Sussex County, Delaware. It was in force for 52 min. 5 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 22, 2017, 3:38 PM EDT (19:38 UTC)
Expired
Jul 22, 2017, 4:30 PM EDT
In force
52 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

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

The radar

The Dover AFB radar (KDOX), 52 km from the middle of the area, began a volume at 19:37 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.

What was reported inside it

TimeReportWhereRemark
Jul 22, 3:40 PM EDTTSTM WND GST 48Easton, MD
Jul 22, 3:43 PM EDTTSTM WND DMGEaston, MDTREE DOWN. TIME ESTIMATED FROM RADAR.
Jul 22, 3:56 PM EDTTSTM WND DMGTrappe, MDTWO TREES DOWN BLOCKING ROADWAY.
Jul 22, 3:56 PM EDTTSTM WND DMGTrappe, MDTWO TREES DOWN BLOCKING ROADWAY. TIME ESTIMATED FROM RADAR.
Jul 22, 4:00 PM EDTTSTM WND DMGTrappe, MDTREES DOWN AND A ROOF DAMAGED ALONG JAMAICA POINT ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.6 hours before the alert went out and 97 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 2017-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 83 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 2017-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 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
83 J/kg
Mixed-layer CIN
-191 J/kg
Mixed-layer LCL
1397 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

745 
WUUS51 KPHI 221938
SVRPHI
DEC005-MDC011-035-041-222030-
/O.NEW.KPHI.SV.W.0115.170722T1938Z-170722T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
338 PM EDT SAT JUL 22 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern Sussex County in southern Delaware...
  Talbot County in eastern Maryland...
  South central Queen Anne's County in northeastern Maryland...
  Southern Caroline County in eastern Maryland...

* Until 430 PM EDT

* At 336 PM EDT, severe thunderstorms were located along a line
  extending from near Grasonville to near Oxford to 8 miles south of
  Tilghman Island, moving southeast at 35 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar and public indicated. This storm has a history of 
           producing wind damage in central and eastern Maryland. At 
           318 PM, a 62 mph wind gust was reported on the southern 
           end of Kent Island.           

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Easton, Seaford, Federalsburg, Bridgeville, Trappe, St. Michaels,
  Preston, Oxford, Tanyard, Harmony, Smithville, Skipton,
  Copperville, Agner, Matthews, Choptank, Hambleton, Griffin,
  Windyhill and Cordova.

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
flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3847 7569 3864 7571 3869 7577 3868 7593
      3857 7602 3871 7622 3868 7634 3868 7635
      3874 7627 3874 7625 3873 7624 3872 7628
      3872 7623 3882 7623 3879 7619 3895 7621
      3879 7557 3847 7562 3846 7562 3846 7569
TIME...MOT...LOC 1936Z 296DEG 28KT 3893 7618 3873 7619 3863 7636 

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

JRK
3 follow-up statements
078 
WWUS51 KPHI 222004
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
404 PM EDT SAT JUL 22 2017

MDC035-222013-
/O.CAN.KPHI.SV.W.0115.000000T0000Z-170722T2030Z/
Queen Anne's MD-
404 PM EDT SAT JUL 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL QUEEN ANNE'S
COUNTY IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 3866 7615 3877 7599 3882 7592 3875 7558
      3847 7562 3846 7562 3846 7569 3847 7569
      3864 7571 3869 7577 3868 7593 3857 7602
TIME...MOT...LOC 2003Z 295DEG 28KT 3877 7594 3864 7597 3854 7614 

$$

DEC005-MDC011-041-222030-
/O.CON.KPHI.SV.W.0115.000000T0000Z-170722T2030Z/
Sussex DE-Talbot MD-Caroline MD-
404 PM EDT SAT JUL 22 2017

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

At 403 PM EDT, severe thunderstorms were located along a line
extending from near Tanyard to near Windyhill to near University Of
Maryland Center For Environmental Studies, moving southeast at 30
mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar and public indicated. This storm has a history of 
         producing sporadic wind damage in central and eastern 
         portions of Maryland.

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Seaford, Federalsburg, Bridgeville, Trappe, Preston, Tanyard,
Harmony, Smithville, Agner, Choptank, Hambleton, Windyhill, Blades
and Bethel.

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.

&&

LAT...LON 3866 7615 3877 7599 3882 7592 3875 7558
      3847 7562 3846 7562 3846 7569 3847 7569
      3864 7571 3869 7577 3868 7593 3857 7602
TIME...MOT...LOC 2003Z 295DEG 28KT 3877 7594 3864 7597 3854 7614 

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

JRK
753 
WWUS51 KPHI 222017
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
417 PM EDT SAT JUL 22 2017

MDC041-222026-
/O.CAN.KPHI.SV.W.0115.000000T0000Z-170722T2030Z/
Talbot MD-
417 PM EDT SAT JUL 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN TALBOT COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 3864 7571 3868 7576 3869 7580 3869 7575
      3867 7559 3846 7562 3846 7569
TIME...MOT...LOC 2016Z 299DEG 35KT 3867 7582 3857 7580 3849 7587 

$$

DEC005-MDC011-222030-
/O.CON.KPHI.SV.W.0115.000000T0000Z-170722T2030Z/
Sussex DE-Caroline MD-
417 PM EDT SAT JUL 22 2017

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

At 416 PM EDT, severe thunderstorms were located along a line
extending from near Federalsburg to near Sharptown to near Vienna,
moving southeast at 40 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Seaford, Blades and Bethel. 

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.

&&

LAT...LON 3864 7571 3868 7576 3869 7580 3869 7575
      3867 7559 3846 7562 3846 7569
TIME...MOT...LOC 2016Z 299DEG 35KT 3867 7582 3857 7580 3849 7587 

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

JRK
157 
WWUS51 KPHI 222030
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
430 PM EDT SAT JUL 22 2017

DEC005-MDC011-222040-
/O.EXP.KPHI.SV.W.0115.000000T0000Z-170722T2030Z/
Sussex DE-Caroline MD-
430 PM EDT SAT JUL 22 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN SUSSEX AND
SOUTHEASTERN CAROLINE COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have weakened below severe 
limits and have exited the warned area. Therefore the warning has 
been allowed to expire.  However gusty winds and heavy rain are 
still possible with these thunderstorms.

LAT...LON 3864 7571 3868 7576 3869 7580 3869 7575
      3867 7559 3846 7562 3846 7569
TIME...MOT...LOC 2030Z 296DEG 28KT 3863 7571 3853 7569 3845 7576 

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 3:03 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot42 min
Jul 22, 4:30 PM EDTSpecial Weather StatementPHIWicomico30 min
Jul 22, 6:44 PM EDTSpecial Weather StatementPHITalbot76 min
Jul 22, 10:45 AM EDTCoastal Flood AdvisoryPHIKent, Sussex13 hr
Jul 22, 2:58 PM EDTSpecial Weather StatementPHISussex62 min
Jul 22, 3:17 PM EDTSevere Thunderstorm WarningPHISussex43 min
Jul 22, 3:34 PM EDTSpecial Weather StatementPHISussex41 min
Jul 22, 3:36 PM EDTAreal Flood AdvisoryPHISussex114 min
Jul 22, 3:57 PM EDTSpecial Weather StatementPHISussex33 min
Jul 22, 5:18 PM EDTSevere Thunderstorm WarningPHINew Castle42 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2017Severe Thunderstorm Warnings in Delaware, 2017Every severe thunderstorm warning in 2017

Sources

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