Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 310, NWS Baltimore/Washington

July 22, 2011Frederick County, Washington County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 22, 2011, 3:07 PM EDT for Frederick County, Washington County, Maryland. It was in force for 45 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
Jul 22, 2011, 3:07 PM EDT (19:07 UTC)
Expired
Jul 22, 2011, 3:52 PM EDT
In force
45 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Frederick County, MD, Washington County, MD

The radar

The Sterling radar (KLWX), 66 km from the middle of the area, began a volume at 19:09 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 22, 3:26 PM EDTTSTM WND DMG3 Sse Wolfsville, MDA COUPLE OF TREES WERE DOWN ALONG ROUTE 17 NEAR MEETINGHOUSE ROAD.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.1 hours before the alert went out and 70 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 2011-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2227 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 2011-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939Sfc1 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
2227 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
1296 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

564 
WUUS51 KLWX 221907 RRA
SVRLWX
MDC021-043-222015-
/O.NEW.KLWX.SV.W.0310.110722T1907Z-110722T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
307 PM EDT FRI JUL 22 2011

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN WASHINGTON COUNTY IN NORTH CENTRAL MARYLAND...
  CENTRAL FREDERICK COUNTY IN NORTH CENTRAL MARYLAND...

* UNTIL 415 PM EDT

* AT 304 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR BOONSBORO...OR 8 MILES
  SOUTHEAST OF HAGERSTOWN...AND MOVING EAST AT 5 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WOLFSVILLE...
  THURMONT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WIND GUSTS AND FREQUENT CLOUD TO GROUND
LIGHTNING. MOVE INDOORS TO A STURDY BUILDING AND STAY AWAY FROM
WINDOWS.

&&

LAT...LON 3966 7737 3945 7736 3948 7771 3961 7771
TIME...MOT...LOC 1908Z 270DEG 3KT 3955 7761

$$

SMZ
2 follow-up statements
896 
WWUS51 KLWX 221923
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
323 PM EDT FRI JUL 22 2011

MDC021-043-222015-
/O.CON.KLWX.SV.W.0310.000000T0000Z-110722T2015Z/
WASHINGTON MD-FREDERICK MD-
323 PM EDT FRI JUL 22 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR FREDERICK AND WASHINGTON COUNTIES...

AT 322 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR WOLFSVILLE...OR 9
MILES SOUTHEAST OF HAGERSTOWN...MOVING EAST AT 5 MPH.

LOCATIONS IMPACTED INCLUDE...
  MYERSVILLE...
  WOLFSVILLE...
  LEWISTOWN...
  THURMONT...
  BLOOMFIELD...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WIND GUSTS AND FREQUENT CLOUD TO GROUND
LIGHTNING. MOVE INDOORS TO A STURDY BUILDING AND STAY AWAY FROM
WINDOWS.

&&

LAT...LON 3965 7740 3947 7739 3949 7762 3960 7762
TIME...MOT...LOC 1924Z 270DEG 6KT 3956 7757

$$

SMZ
389 
WWUS51 KLWX 221952
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
352 PM EDT FRI JUL 22 2011

MDC021-043-222003-
/O.CAN.KLWX.SV.W.0310.000000T0000Z-110722T2015Z/
WASHINGTON MD-FREDERICK MD-
352 PM EDT FRI JUL 22 2011

...THE SEVERE THUNDERSTORM WARNING IS CANCELLED FOR FREDERICK AND
WASHINGTON COUNTIES...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS. THUS THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

LAT...LON 3965 7740 3947 7739 3949 7762 3960 7762
TIME...MOT...LOC 1953Z 270DEG 6KT 3956 7751

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 2:00 PM EDTSpecial Weather StatementLWXWashington30 min
Jul 22, 2:07 PM EDTSevere Thunderstorm WarningLWXAllegany38 min
Jul 22, 2:07 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington38 min
Jul 22, 2:43 PM EDTSevere Thunderstorm WarningLWXWashington47 min
Jul 22, 2:56 PM EDTFlash Flood WarningLWXWashington106 min
Jul 22, 3:07 PM EDTSevere Thunderstorm WarningLWXWashington38 min
Jul 22, 3:15 PM EDTSpecial Weather StatementLWXAllegany30 min
Jul 22, 3:28 PM EDTSpecial Weather StatementLWXFrederick32 min
Jul 22, 3:33 PM EDTSpecial Weather StatementLWXWashington27 min
Jul 22, 4:26 PM EDTSpecial Weather StatementLWXMontgomery19 min
Jul 22, 4:30 PM EDTSevere Thunderstorm WarningLWXMontgomery45 min
Jul 22, 7:35 PM EDTSpecial Weather StatementLWXAllegany20 min
Jul 22, 7:59 PM EDTSpecial Weather StatementLWXAllegany16 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2011Every severe thunderstorm warning in 2011

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.