Alert archive / Maryland / Tornado Warnings in 2021

Tornado Warning 27, NWS Baltimore/Washington

August 18, 2021Baltimore County, Maryland

NWS Baltimore/Washington issued this tornado warning at Aug 18, 2021, 8:57 PM EDT for Baltimore County, Maryland. It was in force for 22 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 18, 2021, 8:57 PM EDT (00:57 UTC)
Expired: Aug 18, 2021, 9:19 PM EDT
In force: 22 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Baltimore County, MD

The radar

The Sterling radar (KLWX), 100 km from the middle of the area, began a volume at 00:56 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.

Issued	Product	Office	Lasted
Aug 18, 11:37 AM EDT	Tornado Watch	SPC	11 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 1.0 hours before the alert went out and 98 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: 1288 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 1100 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 171 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 5.9

Open this sounding in Storm Lab

The text

As transmitted.

762 
WFUS51 KLWX 190057
TORLWX
MDC005-190130-
/O.NEW.KLWX.TO.W.0027.210819T0057Z-210819T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Baltimore MD/Washington DC
857 PM EDT Wed Aug 18 2021

The National Weather Service in Sterling Virginia has issued a

* Tornado Warning for...
  North central Baltimore County in northern Maryland...

* Until 930 PM EDT.
    
* At 857 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Hampstead, or 13 miles southeast of Parkville,
  moving northeast at 35 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.

* This tornadic thunderstorm will remain over mainly rural areas of
  north central Baltimore County, including the following
  locations... Freeland, Bentley Springs and Maryland Line.

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.

&&

LAT...LON 3962 7676 3966 7681 3972 7677 3972 7659
TIME...MOT...LOC 0057Z 223DEG 28KT 3966 7675 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

KLW

2 follow-up statements

439 
WWUS51 KLWX 190107
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
907 PM EDT Wed Aug 18 2021

MDC005-190130-
/O.CON.KLWX.TO.W.0027.000000T0000Z-210819T0130Z/
Baltimore MD-
907 PM EDT Wed Aug 18 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 930 PM EDT FOR NORTH
CENTRAL BALTIMORE COUNTY...
    
At 907 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Railroad, or 14 miles south of Dallastown, moving
northeast at 25 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...
Freeland, Bentley Springs and Maryland Line. 

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.

&&

LAT...LON 3965 7671 3966 7675 3972 7672 3972 7659
TIME...MOT...LOC 0107Z 229DEG 22KT 3969 7669 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

KLW

386 
WWUS51 KLWX 190119
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
919 PM EDT Wed Aug 18 2021

MDC005-190129-
/O.CAN.KLWX.TO.W.0027.000000T0000Z-210819T0130Z/
Baltimore MD-
919 PM EDT Wed Aug 18 2021

...THE TORNADO WARNING FOR NORTH CENTRAL BALTIMORE COUNTY IS
CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.

LAT...LON 3965 7671 3966 7675 3972 7672 3972 7659
TIME...MOT...LOC 0119Z 223DEG 28KT 3976 7660 

$$

KLW

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 11:59 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Cecil	2 hr
Aug 19, 2:11 PM EDT	Flash Flood Watch	LWX	Allegany, Anne Arundel, Baltimore, Calvert, Charles, Howard and 4 more	28 hr

Nearby

Tornado Warnings in Maryland, 2021 Every tornado warning in 2021 Tornadoes 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.