Alert archive / Virginia / Severe Thunderstorm Warnings in 2005

Severe Thunderstorm Warning 91, NWS Baltimore/Washington

July 21, 2005Rockingham County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 21, 2005, 4:29 PM EDT for Rockingham County, Virginia. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 21, 2005, 4:29 PM EDT (20:29 UTC)
Expired: Jul 21, 2005, 4:52 PM EDT
In force: 23 min
Issued by: NWS Baltimore/Washington
Area: Counties, with a storm outline in the text

County Rockingham County, VA

The radar

The Sterling radar (KLWX), 131 km from the middle of the area, began a volume at 20:30 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 12:00Z, 8.5 hours before the alert went out and 137 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1651 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 68 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Baltimore/Washington wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 2:51 PM EDT, 1 hour 38 minutes earlier.

Area forecast discussion, Jul 21, 2:51 PM EDT, 1 hour 38 minutes before

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Hazardous weather outlook, Jul 21, 4:00 PM EDT, 29 minutes before

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In the hours before

Special weather statement, Jul 21, 1:56 PM EDT, 2 hours 33 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
156 PM EDT THU JUL 21 2005

VAZ031-211830-
CLARKE VA-
156 PM EDT THU JUL 21 2005

AT 155 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR
WINCHESTER...MOVING SOUTHEAST AT 15 MPH. THIS STORM WILL ENTER
WESTERN CLARK COUNTY AROUND 210 PM AND WILL BE CAPABLE OF PRODUCING
SMALL HAIL...DANGEROUS CLOUD TO GROUND LIGHTNING AND WIND GUSTS TO
40 MPH. ONE HALF DIAMETER HAIL HAS BEEN REPORTED WITH THIS STORM IN
WINCHESTER. THE COMMUNITIES OF BERRYVILLE...BOYCE...MILLWOOD AND
WHITE POST WILL BE AFFECTED BY THIS STORM THROUGH 230 PM EDT.

SMZ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 21, 1:50 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, City of Winchester	28 min
Jul 21, 2:16 PM EDT	Severe Thunderstorm Warning	LWX	Clarke	37 min
Jul 21, 4:08 PM EDT	Special Marine Warning	LWX		97 min
Jul 21, 5:43 PM EDT	Special Marine Warning	LWX		2 hr
Jul 21, 6:23 PM EDT	Special Marine Warning	LWX		2 hr
Jul 21, 7:33 PM EDT	Special Marine Warning	LWX		87 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2005 Every severe thunderstorm warning in 2005

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.