Alert archive / Virginia / Severe Thunderstorm Watches in 2000

Severe Thunderstorm Watch 581

July 14, 20004 states

The Storm Prediction Center issued this severe thunderstorm watch at Jul 14, 2000, 4:45 PM EDT for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jul 14, 2000, 4:45 PM EDT (20:45 UTC)
Expired: Jul 14, 2000, 10:00 PM EDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 57 counties

Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Carroll County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Saint Mary's County, MD, Washington County, MD, Adams County, PA, Blair County, PA, Centre County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lebanon County, PA, Lycoming County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Snyder County, PA, Union County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, King George County, VA, Loudoun County, VA, Madison County, VA, Orange County, VA, Prince William County, VA, Rappahannock County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Jefferson County, WV, Morgan County, WV

The radar

The Sterling radar (KLWX), 49 km from the middle of the area, began a volume at 20:45 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.

Warnings issued inside it

12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jul 14, 4:57 PM EDT	Severe Thunderstorm Warning	CTP	Snyder	63 min
Jul 14, 5:05 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming	55 min
Jul 14, 5:51 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, City of Baltimore	69 min
Jul 14, 6:09 PM EDT	Flash Flood Warning	CTP	Lancaster, York	3 hr
Jul 14, 6:10 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	50 min
Jul 14, 6:25 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	110 min
Jul 14, 6:36 PM EDT	Severe Thunderstorm Warning	LWX	Charles	54 min
Jul 14, 8:15 PM EDT	Severe Thunderstorm Warning	LWX	Washington	45 min
Jul 14, 8:20 PM EDT	Severe Thunderstorm Warning	CTP	Franklin	55 min
Jul 14, 8:24 PM EDT	Severe Thunderstorm Warning	LWX	Prince William, City of Manassas, City of Manassas Park	66 min
Jul 14, 8:51 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Warren	39 min
Jul 14, 9:15 PM EDT	Flash Flood Warning	CTP	Lancaster, York	3 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.8 hours before the alert went out and 53 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: 143 J/kg
Mixed-layer CIN: -116 J/kg
Mixed-layer LCL: 783 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

117 
WWUS9 KMKC 142037
SEL1  

SEL1  
MKC WW 142026
DCZ000-MDZ000-PAZ000-VAZ000-WVZ000-150200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 581
STORM PREDICTION CENTER NORMAN OK
426 PM EDT FRI JUL 14 2000

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   DISTRICT OF COLUMBIA
   MARYLAND                           
   CENTRAL PENNSYLVANIA                       
   NORTHERN VIRGINIA                           
   EASTERN WEST VIRGINIA                      

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 445 PM UNTIL 1000
PM EDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 55 STATUTE MILES
EAST AND WEST OF A LINE FROM 55 MILES SOUTH SOUTHWEST OF WASHINGTON
DC TO 20 MILES WEST NORTHWEST OF WILLIAMSPORT PENNSYLVANIA.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...  CONTINUE...WW 577...WW 578...WW
579...WW 580...

DISCUSSION...THUNDERSTORMS ARE INCREASING ALONG THE LEE TROUGH OVER
THE CENTRAL APPALACHIANS. ACTIVITY APPEARS TO BE ENHANCED BY LEAD
SHORTWAVE TROUGH. WITH JUST ENOUGH SHEAR FOR SUPERCELLS...THREAT
FOR LARGE HAIL AND WIND DAMAGE SHOULD CONTINUE INTO THE EVENING.


AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 26020.

...VESCIO

412,0761 380,0762 380,0782 412,0782

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 14, 4:15 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Garrett	6 hr
Jul 14, 1:00 PM EDT	Severe Thunderstorm Watch	SPC	Beaver, Butler, Crawford, Erie, Lawrence, Mercer and 1 more	6 hr
Jul 14, 6:30 PM EDT	Severe Thunderstorm Watch	SPC	Buchanan, Dickenson, Wise, City of Norton	4 hr
Jul 14, 2:30 PM EDT	Severe Thunderstorm Watch	SPC	Cabell, Jackson, Mason, Putnam	6 hr

Nearby

Severe Thunderstorm Watches in Virginia, 2000 Severe Thunderstorm Watches in Pennsylvania, 2000 Severe Thunderstorm Watches in Maryland, 2000 Every severe thunderstorm watch in 2000

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.