Alert archive / Maryland / Tornado Warnings in 2021

Tornado Warning 21, NWS Baltimore/Washington

July 29, 2021Howard County, Maryland

NWS Baltimore/Washington issued this tornado warning at Jul 29, 2021, 4:34 PM EDT for Howard County, Maryland. It was in force for 26 min. 3 reports 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
Jul 29, 2021, 4:34 PM EDT (20:34 UTC)
Expired
Jul 29, 2021, 5:00 PM EDT
In force
26 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

County Howard County, MD

The radar

The Sterling radar (KLWX), 64 km from the middle of the area, began a volume at 20:33 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
Jul 29, 4:35 PM EDTTSTM WND DMG1 Se Gaither, MDTREE DAMAGE WAS REPORTED NEAR GAITHER, INCLUDING NEAR THE INTERSECTION OF GAITHER ROAD AND FORSYTHE ROAD.
Jul 29, 4:52 PM EDTTSTM WND DMG3 Wnw Historic Ellicott, MDTREES BLEW DOWN ON WESTBOUND US-40 BALTIMORE NATIONAL PIKE AT BETHANY LANE.
Jul 29, 5:00 PM EDTTSTM WND DMG2 Nne Historic Ellicott, MDSEVERAL TREES BLEW DOWN IN PATAPSCO VALLEY STATE PARK.

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
Jul 29, 2:23 PM EDTTornado WatchSPC8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.6 hours before the alert went out and 60 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 12:00Z on 2021-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 269 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 12:00Z on 2021-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 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
269 J/kg
Mixed-layer CIN
-91 J/kg
Mixed-layer LCL
893 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
62 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

055 
WFUS51 KLWX 292034
TORLWX
MDC027-292100-
/O.NEW.KLWX.TO.W.0021.210729T2034Z-210729T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Baltimore MD/Washington DC
434 PM EDT Thu Jul 29 2021

The National Weather Service in Sterling Virginia has issued a

* Tornado Warning for...
  Northeastern Howard County in central Maryland...

* Until 500 PM EDT.
    
* At 434 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Sykesville, or 11 miles northeast of Damascus,
  moving east at 25 mph.

  HAZARD...Tornado and quarter size hail.

  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 dangerous storm will be near...
  Ellicott City around 455 PM EDT.
  Columbia, Historic Ellicott City, Catonsville and Woodlawn around 
  500 PM EDT.

Other locations impacted by this tornadic thunderstorm include West
Friendship, Daniels and Woodstock.

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 3934 7688 3932 7685 3932 7680 3930 7678
      3927 7679 3926 7679 3921 7682 3933 7706
      3935 7703 3936 7700
TIME...MOT...LOC 2034Z 287DEG 20KT 3934 7701 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

DHOF
1 follow-up statement
375 
WWUS51 KLWX 292046
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
446 PM EDT Thu Jul 29 2021

MDC027-292100-
/O.CON.KLWX.TO.W.0021.000000T0000Z-210729T2100Z/
Howard MD-
446 PM EDT Thu Jul 29 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM EDT FOR
NORTHEASTERN HOWARD COUNTY...
    
At 446 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Sykesville, or 7 miles northwest of Historic
Ellicott City, moving east at 25 mph.

HAZARD...Tornado and quarter size hail.

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 dangerous storm will be near...
  Ellicott City around 455 PM EDT.
  Historic Ellicott City around 500 PM EDT.
  Columbia and Catonsville around 505 PM EDT.
  Woodlawn around 515 PM EDT.

Other locations impacted by this tornadic thunderstorm include West
Friendship and Daniels.

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 3932 7685 3932 7680 3930 7678 3927 7679
      3926 7679 3921 7682 3929 7698 3934 7694
TIME...MOT...LOC 2046Z 287DEG 20KT 3932 7693 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

DHOF

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 9:30 PM EDTSevere Thunderstorm WarningLWXMontgomery45 min
Jul 28, 9:48 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's42 min
Jul 29, 3:31 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick44 min
Jul 29, 4:00 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll45 min
Jul 29, 4:01 PM EDTTornado WarningLWXCarroll29 min
Jul 29, 4:16 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Howard44 min
Jul 29, 4:40 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's50 min
Jul 29, 4:50 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Howard, City of Baltimore55 min
Jul 29, 4:59 PM EDTSevere Thunderstorm WarningLWXCharles46 min
Jul 29, 4:59 PM EDTTornado WarningLWXAnne Arundel, Baltimore, Howard31 min
Jul 29, 5:01 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's29 min
Jul 29, 5:30 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Prince George's40 min
Jul 29, 5:43 PM EDTSevere Thunderstorm WarningLWXAnne Arundel17 min
Jul 29, 6:49 PM EDTCoastal Flood AdvisoryLWXAnne Arundel4 hr

Nearby

Tornado Warnings in Maryland, 2021Every tornado warning in 2021Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.