Alert archive / Virginia / Tornado Watches in 2001

Tornado Watch 758

September 24, 20014 states

The Storm Prediction Center issued this tornado watch at Sep 24, 2001, 1:30 PM EDT for 4 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Sep 24, 2001, 1:30 PM EDT (17:30 UTC)
Expired
Sep 24, 2001, 8:00 PM EDT
In force
7 hr
Issued by
the Storm Prediction Center
All 94 counties

Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Carroll County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Saint Mary's County, MD, Washington County, MD, Bertie County, NC, Chowan County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Halifax County, NC, Hertford County, NC, Martin County, NC, Nash County, NC, Northampton County, NC, Perquimans County, NC, Warren County, NC, Washington County, NC, Wilson County, NC, Amelia County, VA, Arlington County, VA, Brunswick County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Alexandria, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Fairfax, VA, City of Falls Church, VA, City of Franklin, VA, City of Fredericksburg, VA, City of Hopewell, VA, City of Manassas, VA, City of Manassas Park, VA, City of Newport News, VA, City of Petersburg, VA, City of Richmond, VA, City of Suffolk, VA, City of Williamsburg, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Fluvanna County, VA, Frederick County, VA, Gloucester County, VA, Goochland County, VA, Greensville County, VA, Hanover County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Lancaster County, VA, Loudoun County, VA, Louisa County, VA, Lunenburg County, VA, Madison County, VA, Middlesex County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Powhatan County, VA, Prince George County, VA, Prince William County, VA, Rappahannock County, VA, Richmond County, VA, Southampton County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Warren County, VA, Westmoreland County, VA, York County, VA, Berkeley County, WV, Jefferson County, WV, Morgan County, WV

The radar

The Norfolk radar (KAKQ), 58 km from the middle of the area, began a volume at 17:31 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

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

IssuedProductOfficeCountiesLasted
Sep 24, 2:36 PM EDTTornado WarningLWXCulpeper34 min
Sep 24, 3:08 PM EDTTornado WarningLWXCulpeper, Fauquier37 min
Sep 24, 3:33 PM EDTTornado WarningAKQDinwiddie, City of Petersburg27 min
Sep 24, 3:45 PM EDTTornado WarningLWXFauquier30 min
Sep 24, 4:00 PM EDTTornado WarningLWXFauquier, Loudoun45 min
Sep 24, 4:09 PM EDTTornado WarningLWXPrince William, Stafford36 min
Sep 24, 4:53 PM EDTTornado WarningLWXArlington, Fairfax, City of Alexandria37 min
Sep 24, 4:53 PM EDTTornado WarningLWXCity of Falls Church37 min
Sep 24, 5:10 PM EDTTornado WarningLWXMontgomery, Prince George's35 min
Sep 24, 5:31 PM EDTTornado WarningLWXAnne Arundel, Howard29 min
Sep 24, 5:34 PM EDTTornado WarningAKQBertie, Hertford26 min
Sep 24, 6:00 PM EDTTornado WarningAKQHertford30 min
Sep 24, 6:15 PM EDTFlash Flood WarningLWXFrederick2 hr

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 5.5 hours before the alert went out and 174 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, Roanoke, VA at 12:00Z on 2001-09-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 81 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 12:00Z on 2001-09-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 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
81 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
792 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
100 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.

582 
WWUS9 KMKC 241725
SEL8  
MKC WW 241719
DCZ000-MDZ000-NCZ000-VAZ000-WVZ000-250000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 758
STORM PREDICTION CENTER NORMAN OK
119 PM EDT MON SEP 24 2001

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   DISTRICT OF COLUMBIA
   WESTERN AND CENTRAL MARYLAND                           
   NORTHEAST NORTH CAROLINA                     
   CENTRAL AND EASTERN VIRGINIA                           
   THE EASTERN PANHANDLE OF WEST VIRGINIA                      

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 130 PM UNTIL 800
PM EDT.

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

THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES EAST AND WEST
OF A LINE FROM 30 MILES EAST SOUTHEAST OF ROCKY MOUNT NORTH
CAROLINA TO 25 MILES EAST OF HAGERSTOWN MARYLAND.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

DISCUSSION...SURFACE MESOLOW AND ASSOCIATED PRESSURE RISE/FALL
COUPLET IS FORECAST TO TRACK NORTHEASTWARD ACROSS NORTHERN NC INTO
VA THIS AFTERNOON.  LOCALLY ENHANCED LOW LEVEL SHEAR PROFILES AND
MODERATE INSTABILITY WILL PROMOTE SUPERCELL STORM POTENTIAL. 
DAMAGING WINDS AND ISOLATED TORNADOES APPEAR TO BE THE MAIN
THREATS.

AVIATION...TORNADOES AND 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 22030.

...HART

394,0761 354,0762 354,0782 394,0781

Nearby

Tornado Watches in Virginia, 2001Tornado Watches in North Carolina, 2001Tornado Watches in Maryland, 2001Every tornado watch in 2001

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.