Alert archive / Maryland / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 287, NWS Philadelphia/Mount Holly

September 2, 20205 counties in Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 2, 2020, 8:47 PM EDT for 5 counties in Maryland. It was in force for 58 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
Sep 2, 2020, 8:47 PM EDT (00:47 UTC)
Expired
Sep 2, 2020, 9:45 PM EDT
In force
58 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 69 km from the middle of the area, began a volume at 00:48 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
Sep 2, 6:43 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.8 hours before the alert went out and 104 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, Washington/Dulle, VA at 00:00Z on 2020-09-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1723 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, Washington/Dulle, VA at 00:00Z on 2020-09-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 182 square meters per square second.193958Sfc1 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
1723 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
847 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
182 m²/s²
0-3 km storm-relative helicity
229 m²/s²
Significant tornado parameter
1.4
Supercell composite
8.6

Open this sounding in Storm Lab

The text

As transmitted.

845 
WUUS51 KPHI 030047
SVRPHI
MDC011-015-029-035-041-030145-
/O.NEW.KPHI.SV.W.0287.200903T0047Z-200903T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
847 PM EDT Wed Sep 2 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern Talbot County in eastern Maryland...
  Queen Anne's County in northeastern Maryland...
  Central Caroline County in eastern Maryland...
  Kent County in northeastern Maryland...
  Southeastern Cecil County in northeastern Maryland...

* Until 945 PM EDT.

* At 847 PM EDT, severe thunderstorms were located along a line
  extending from Bel Air South to Londontowne, moving southeast at 30
  mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Easton, Centerville, Talbot, Chestertown, Denton, Centreville,
  Romancoke, Greensboro, Oakland, Ridgely, Rock Hall, Church Hill,
  Cecilton, Millington, Sudlersville, Betterton, Goldsboro, Queen
  Anne, Old Town and Grasonville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 3903 7631 3904 7631 3898 7628 3900 7617
      3901 7621 3917 7628 3932 7618 3946 7601
      3941 7577 3876 7580 3882 7631 3883 7619
      3886 7626 3886 7621 3897 7625 3891 7624
      3894 7627 3884 7637
TIME...MOT...LOC 0047Z 295DEG 24KT 3950 7632 3895 7653 

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

Iovino
1 follow-up statement
679 
WWUS51 KPHI 030114
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
914 PM EDT Wed Sep 2 2020

MDC011-015-029-035-041-030145-
/O.CON.KPHI.SV.W.0287.000000T0000Z-200903T0145Z/
Talbot MD-Queen Anne's MD-Caroline MD-Kent MD-Cecil MD-
914 PM EDT Wed Sep 2 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR NORTHERN TALBOT...QUEEN ANNE'S...CENTRAL CAROLINE...KENT AND
SOUTHEASTERN CECIL COUNTIES...

At 913 PM EDT, severe thunderstorms were located along a line
extending from Newtown to Romancoke, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Easton, Centerville, Talbot, Chestertown, Denton, Centreville,
Romancoke, Greensboro, Oakland, Ridgely, Rock Hall, Church Hill,
Cecilton, Millington, Sudlersville, Betterton, Goldsboro, Queen Anne,
Old Town and Grasonville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 3903 7631 3904 7631 3898 7628 3900 7617
      3901 7621 3917 7628 3932 7618 3946 7601
      3941 7577 3876 7580 3882 7631 3883 7619
      3886 7626 3886 7621 3897 7625 3891 7624
      3894 7627 3884 7637
TIME...MOT...LOC 0113Z 275DEG 27KT 3932 7617 3888 7634 

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

Iovino

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 2, 8:07 PM EDTSevere Thunderstorm WarningPHICecil53 min
Sep 2, 10:08 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot67 min
Sep 3, 5:47 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot73 min
Sep 3, 6:48 PM EDTSevere Thunderstorm WarningPHICaroline, Talbot57 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2020Every severe thunderstorm warning in 2020

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.