Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 79, NWS Philadelphia/Mount Holly

July 1, 2017Kent County, Sussex County, Delaware; Caroline County, Queen Anne's County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 1, 2017, 5:39 PM EDT for Kent County, Sussex County, Delaware; Caroline County, Queen Anne's County, Talbot County, Maryland. It was in force for 51 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 1, 2017, 5:39 PM EDT (21:39 UTC)
Expired
Jul 1, 2017, 6:30 PM EDT
In force
51 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

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), 48 km from the middle of the area, began a volume at 21:39 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 1, 1:34 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 9.7 hours before the alert went out and 101 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 2017-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 96 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 2017-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 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
96 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

456 
WUUS51 KPHI 012139
SVRPHI
DEC001-005-MDC011-035-041-012230-
/O.NEW.KPHI.SV.W.0079.170701T2139Z-170701T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
539 PM EDT SAT JUL 1 2017

The National Weather Service in Mount Holly NJ has issued a

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

* Until 630 PM EDT

* At 538 PM EDT, severe thunderstorms were located along a line
  extending from near Oakland to Oxford, moving southeast at 15 mph.

  HAZARD...60 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Easton, Denton, Harrington, Camden, Federalsburg, Greensboro,
  Oakland, Ridgely, Trappe, Preston, Oxford, Bowers, Goldsboro, Queen
  Anne, Woodside, Viola, Smithville, Rising Sun-Lebanon, Starr and
  Jumptown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3863 7608 3864 7615 3868 7617 3869 7619
      3867 7620 3871 7621 3871 7624 3913 7592
      3909 7537 3864 7571 3869 7577 3868 7580
      3871 7584 3870 7590 3866 7596 3860 7599
      3857 7604
TIME...MOT...LOC 2138Z 303DEG 13KT 3904 7590 3867 7617 

HAIL...0.75IN
WIND...60MPH
 
$$

SFJ
2 follow-up statements
783 
WWUS51 KPHI 012154
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
554 PM EDT SAT JUL 1 2017

DEC001-005-MDC011-035-041-012230-
/O.CON.KPHI.SV.W.0079.000000T0000Z-170701T2230Z/
Sussex DE-Kent DE-Talbot MD-Queen Anne's MD-Caroline MD-
554 PM EDT SAT JUL 1 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR WEST CENTRAL SUSSEX...SOUTHERN KENT...EASTERN TALBOT...
SOUTHEASTERN QUEEN ANNE'S AND CAROLINE COUNTIES...

At 553 PM EDT, severe thunderstorms were located along a line
extending from Greensboro to near Trappe, moving southeast at 20 mph.

HAZARD...60 mph wind gusts and penny size hail. 

SOURCE...Radar indicated. 

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

Locations impacted include...
Easton, Denton, Harrington, Camden, Federalsburg, Greensboro,
Oakland, Ridgely, Trappe, Preston, Bowers, Goldsboro, Queen Anne,
Woodside, Viola, Smithville, Jumptown, Agner, Choptank and Windyhill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3863 7608 3864 7615 3912 7586 3909 7537
      3864 7571 3869 7577 3868 7580 3870 7580
      3871 7584 3870 7590 3868 7594 3860 7599
      3857 7604
TIME...MOT...LOC 2153Z 300DEG 17KT 3900 7581 3863 7608 

HAIL...0.75IN
WIND...60MPH
 
$$

SFJ
269 
WWUS51 KPHI 012226
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
626 PM EDT SAT JUL 1 2017

DEC001-005-MDC011-035-041-012234-
/O.EXP.KPHI.SV.W.0079.000000T0000Z-170701T2230Z/
Sussex DE-Kent DE-Talbot MD-Queen Anne's MD-Caroline MD-
626 PM EDT SAT JUL 1 2017

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL SUSSEX...SOUTHERN
KENT...EASTERN TALBOT...SOUTHEASTERN QUEEN ANNE'S AND CAROLINE
COUNTIES WILL EXPIRE AT 630 PM EDT...
            
The northern half of the line of storms which prompted the warning 
have weakened below severe limits, and no longer pose an immediate 
threat to life or property. Therefore the warning will be allowed to 
expire.  However gusty winds are still possible with these 
thunderstorms. Additionally, a severe thunderstorm warning remains 
in effect for the southern portion of this line including portions 
of Dorchester and Wicomico Counties in Maryland.

A severe thunderstorm watch remains in effect until 900 PM EDT for
central and southern Delaware...and eastern and northeastern
Maryland.

LAT...LON 3863 7608 3864 7615 3912 7586 3909 7537
      3864 7571 3869 7577 3868 7580 3870 7580
      3871 7584 3870 7590 3868 7594 3860 7599
      3857 7604
TIME...MOT...LOC 2224Z 260DEG 27KT 3904 7553 3867 7580 

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 1, 5:01 PM EDTSevere Thunderstorm WarningPHINew Castle44 min
Jul 1, 5:30 PM EDTAreal Flood AdvisoryPHINew Castle4 hr
Jul 1, 5:41 PM EDTSpecial Weather StatementPHIKent, New Castle34 min
Jul 1, 6:27 PM EDTSpecial Weather StatementPHIKent33 min
Jul 1, 4:12 PM EDTSpecial Weather StatementPHICecil, Kent, Queen Anne's, Talbot33 min
Jul 1, 4:38 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's67 min
Jul 1, 5:03 PM EDTSpecial Weather StatementPHIQueen Anne's, Talbot27 min
Jul 1, 5:20 PM EDTAreal Flood AdvisoryPHICecil, Kent, Queen Anne's4 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.