Alert archive / Maryland / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

August 20, 2021Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 20, 2021, 5:39 AM EDT for Caroline County, Maryland. It was in force for 36 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 20, 2021, 5:39 AM EDT (09:39 UTC)
Expired: Aug 20, 2021, 6:15 AM EDT
In force: 36 min
Issued by: NWS Philadelphia/Mount Holly
Hail: 0.25 in
Wind: 40

County Caroline County, MD

The radar

The Dover AFB radar (KDOX), 53 km from the middle of the area, began a volume at 09:38 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 9.7 hours before the alert went out and 117 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 652 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1240 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 14 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

566 
WWUS81 KPHI 200939
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
539 AM EDT Fri Aug 20 2021
 
MDZ015-019-020-201015-
Queen Anne's MD-Talbot MD-Caroline MD-
539 AM EDT Fri Aug 20 2021

...A strong thunderstorm will impact portions of northeastern Talbot,
south central Queen Anne's and central Caroline Counties through 615
AM EDT...

At 538 AM EDT, Doppler radar was tracking a strong thunderstorm over
Skipton, or near Easton, moving northeast at 10 mph.

HAZARD...Wind gusts up to 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Easton, Centerville, Denton, Centreville, Ridgely, Queen Anne, Starr,
Skipton, Jumptown, Matthews, Wye Mills, Griffin, Cordova, Carville,
Hope and Hillsboro.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3878 7611 3890 7620 3911 7602 3884 7579
TIME...MOT...LOC 0938Z 237DEG 9KT 3886 7608 

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

$$

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 19, 8:15 PM EDT	Rip Current Statement	PHI	Atlantic, Cape May, Ocean	3 days
Aug 20, 3:08 AM EDT	Special Weather Statement	PHI	Cumberland	37 min
Aug 20, 3:10 AM EDT	Special Weather Statement	PHI	Atlantic	35 min
Aug 20, 7:25 AM EDT	Special Marine Warning	PHI		65 min
Aug 20, 8:20 AM EDT	Special Marine Warning	PHI		55 min
Aug 20, 8:45 AM EDT	Special Marine Warning	PHI		60 min
Aug 20, 9:36 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Ocean	3 hr
Aug 20, 3:13 PM EDT	Rip Current Statement	PHI	Monmouth	60 hr
Aug 20, 4:48 PM EDT	Tropical Storm Watch	PHI	Middlesex, Monmouth	6 hr
Aug 20, 6:39 AM EDT	Areal Flood Advisory	PHI	Kent	8 hr
Aug 20, 6:46 AM EDT	Areal Flood Advisory	PHI	Sussex	3 hr
Aug 20, 8:18 AM EDT	Areal Flood Advisory	PHI	Kent, Sussex	117 min
Aug 20, 6:09 AM EDT	Special Weather Statement	PHI	Caroline	36 min
Aug 20, 11:07 AM EDT	Areal Flood Advisory	PHI	Caroline, Talbot	3 hr

Nearby

Special Weather Statements in Maryland, 2021 Every special weather statement in 2021

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.