Alert archive / Maryland / Tornado Warnings in 2020

Tornado Warning 13, NWS Baltimore/Washington

August 4, 2020Anne Arundel County, Calvert County, Maryland

NWS Baltimore/Washington issued this tornado warning at Aug 4, 2020, 7:17 AM EDT for Anne Arundel County, Calvert County, Maryland. It was in force for 28 min. 1 report 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
Aug 4, 2020, 7:17 AM EDT (11:17 UTC)
Expired
Aug 4, 2020, 7:45 AM EDT
In force
28 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

Counties Anne Arundel County, MD, Calvert County, MD

The radar

The Sterling radar (KLWX), 88 km from the middle of the area, began a volume at 11:22 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
Aug 4, 7:35 AM EDTTORNADO4 S Chesapeake Beach, MDMULTIPLE TREES REPORTED DOWN IN THE WILLOW BEACH COLONY AREA.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 4, 2:26 AM EDTTornado WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 11.3 hours before the alert went out and 79 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 2020-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 89 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 2020-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.19395878Sfc1 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
89 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
889 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

078 
WFUS51 KLWX 041117
TORLWX
MDC003-009-041145-
/O.NEW.KLWX.TO.W.0013.200804T1117Z-200804T1145Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Baltimore MD/Washington DC
717 AM EDT Tue Aug 4 2020

The National Weather Service in Sterling Virginia has issued a

* Tornado Warning for...
  South central Anne Arundel County in central Maryland...
  Northwestern Calvert County in southern Maryland...

* Until 745 AM EDT.
    
* At 715 AM EDT, a severe thunderstorm capable of producing a 
  tornado was located over the Chesapeake Bay east of St. Leonard, 
  moving northwest at 45 mph. This tornado is expected to move 
  onshore near Dares Beach around 720 AM EDT.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...For those in the direct path of a tornado touchdown, 
           flying debris will be dangerous to those caught without 
           shelter. Damage to roofs, siding, and windows may occur. 
           Mobile homes may be damaged or destroyed. Tree damage is 
           likely.

* Locations impacted include...
  Chesapeake Beach, Breezy Point, Dunkirk, Huntingtown, Owings,
  Friendship, Mount Harmony, Tracys Landing, Sunderland and Dares
  Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 3862 7666 3882 7667 3874 7652 3873 7651
      3870 7651 3853 7649 3851 7648
TIME...MOT...LOC 1115Z 132DEG 38KT 3851 7643 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

LEE
1 follow-up statement
096 
WWUS51 KLWX 041134
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
734 AM EDT Tue Aug 4 2020

MDC003-009-041145-
/O.CON.KLWX.TO.W.0013.000000T0000Z-200804T1145Z/
Anne Arundel MD-Calvert MD-
734 AM EDT Tue Aug 4 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 745 AM EDT FOR SOUTHERN
ANNE ARUNDEL AND NORTHWESTERN CALVERT COUNTIES...
    
At 734 AM EDT, a severe thunderstorm capable of producing a tornado 
was coming ashore between Chesapeake Beach and Dares Beach, moving 
west at 50 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...For those in the direct path of a tornado touchdown, flying 
         debris will be dangerous to those caught without shelter. 
         Damage to roofs, siding, and windows may occur. Mobile 
         homes may be damaged or destroyed. Tree damage is likely.

Locations impacted include...
Chesapeake Beach, Breezy Point, Dunkirk, Huntingtown, Owings,
Friendship, Mount Harmony and Sunderland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 3860 7660 3862 7666 3875 7666 3870 7651
      3858 7652
TIME...MOT...LOC 1134Z 105DEG 45KT 3863 7654 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

LEE

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 4, 4:01 AM EDTTornado WarningLWXSaint Mary's29 min
Aug 4, 4:47 AM EDTTornado WarningLWXCharles, Saint Mary's28 min
Aug 4, 5:17 AM EDTAreal Flood WarningLWXSaint Mary's6 hr
Aug 4, 6:18 AM EDTTornado WarningLWXCharles, Saint Mary's13 min
Aug 4, 6:41 AM EDTTornado WarningLWXSaint Mary's34 min
Aug 4, 6:44 AM EDTTornado WarningLWXCalvert, Saint Mary's31 min
Aug 4, 6:57 AM EDTFlash Flood Warning Considerable damage threatLWXCalvert, Saint Mary's4 hr
Aug 4, 7:32 AM EDTFlash Flood Warning Considerable damage threatLWXAnne Arundel, Calvert, Charles, Prince George's4 hr
Aug 4, 7:42 AM EDTTornado WarningLWXCalvert, Prince George's8 min
Aug 4, 8:31 AM EDTAreal Flood WarningLWXMontgomery, Prince George's9 hr
Aug 4, 8:39 AM EDTFlash Flood Warning Considerable damage threatLWXAnne Arundel, Baltimore, Prince George's, City of Baltimore4 hr
Aug 4, 9:02 AM EDTFlash Flood Warning Considerable damage threatLWXBaltimore, Harford4 hr
Aug 4, 9:26 AM EDTTornado WarningLWXHarford18 min
Aug 4, 9:31 AM EDTTornado WarningLWXBaltimore11 min
Aug 4, 9:53 AM EDTAreal Flood WarningLWXBaltimore, Carroll, Howard6 hr
Aug 4, 10:47 AM EDTAreal Flood WarningLWXCalvert, Saint Mary's17 hr
Aug 4, 11:20 AM EDTAreal Flood WarningLWXAnne Arundel, Calvert, Charles, Prince George's21 hr
Aug 4, 12:32 PM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Prince George's, City of Baltimore11 hr
Aug 4, 12:53 PM EDTAreal Flood WarningLWXBaltimore, Harford4 hr
Aug 4, 4:32 PM EDTAreal Flood WarningLWXCharles43 hr
Aug 4, 7:18 PM EDTAreal Flood WarningLWXCharles24 hr

Nearby

Tornado Warnings in Maryland, 2020Every tornado warning in 2020Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.