Alert archive / Virginia / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 217, NWS Blacksburg, VA

August 5, 2003Botetourt County, Virginia

NWS Blacksburg, VA issued this severe thunderstorm warning at Aug 5, 2003, 2:48 PM EDT for Botetourt County, Virginia. It was in force for 57 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 5, 2003, 2:48 PM EDT (18:48 UTC)
Expired: Aug 5, 2003, 3:45 PM EDT
In force: 57 min
Issued by: NWS Blacksburg, VA
Area: Counties, with a storm outline in the text

County Botetourt County, VA

The radar

The Roanoke radar (KFCX), 77 km from the middle of the area, began a volume at 18:50 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 6.8 hours before the alert went out and 51 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: 265 J/kg
Mixed-layer CIN: -84 J/kg
Mixed-layer LCL: 728 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 27 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.

907 
WUUS51 KRNK 051848
SVRRNK
VAC023-051945-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BLACKSBURG VA
244 PM EDT TUE AUG 5 2003

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BOTETOURT COUNTY IN WEST CENTRAL VIRGINIA

* UNTIL 345 PM EDT.

* AT 244 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 8 MILES WEST OF TROUTVILLE...MOVING EAST AT 30
  MPH.

* SOME LOCATIONS THREATENED THROUGH 345 PM EDT INCLUDE
  TROUTVILLE...
  EAGLE ROCK...
  BUCHANAN...

THE SEVERE THUNDERSTORM IS CAPABLE OF PRODUCING UP TO NICKEL SIZE 
HAIL AND WINDS UP TO 70 MILES AN HOUR.

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER.

REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...
DAMAGING WINDS IN EXCESS OF 55 MPH...DEADLY LIGHTNING...AND VERY
HEAVY RAIN.

RELAY SEVERE WEATHER REPORTS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1...8 6 6...2 1 5...4 3 2 4.

LAT...LON 3778 7968 3765 7966 3753 7949 3747 7957
          3748 7968 3731 7985 3742 8009 3754 7997
          3764 8004 3772 7991 3780 7983

$$

08

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 Blacksburg, VA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 5, 10:35 AM EDT, 4 hours 13 minutes earlier.

Area forecast discussion, Aug 5, 10:35 AM EDT, 4 hours 13 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG, VA
1035 AM EDT TUE AUG 5 2003

CONVECTIVE ACTIVITY THAT MOVED THROUGH OVERNIGHT HAS STABALIZED
ATMOSPHERE CONSIDERABLY.  DEEPER MOISTURE HAS NOW BEEN SHUNTED EAST
OF THE FCST AREA WITH CONSIDERABLE DRYING AT ALL LEVELS...PWATS NOW
DOWN TO 1.00 TO 1.25.  AS A RESULT...DO NOT FORSEE A FLASH FLOOD
THREAT TODAY.  IF ANYTHING...WESTERLY WINDS SFC AND ALOFT WILL WORK
AGAINST POOLING OF ANY MOISTURE EXCEPT FOR THE WINDWARD SLOPES IN
THE WESTERN PART OF THE CWA.

MODIFIED AFTN RNK SOUNDING YIELDS AFTN CAPES OF 1000-1500 J/KG.  IN
SPITE OF DRY AIR AND WESTERLY WINDS...PRESENCE OF UPPER TROF AND THE
EXIT REGION OF UL JET STREAK TO OUR SW MAY BE ENOUGH TO INITIATE SCT
AFTN DEEP CONVECTION.  WITH COLD AIR ALOFT (5H TEMPS OF M11)...
STEEPENING LL LAPSE RATES FROM AFTN HEATING...AND POTENTIAL FOR DRY
AIR ENTRAINMENT...POTENTIAL EXISTS FOR ISOLD SVR WX...THREAT BEING
LARGE HAIL AND WIND.  VIL OF THE DAY LOOKS TO BE IN THE NEIGHBORHOOD
OF 45...POSSIBLY AS LOW AS 40 IF COOLER TEMPS ABOVE 5H ADVECT ACROSS
THE CWA DURING THE AFTN.

GOING FCST LOOKS GOOD WITH CHC THREAT THE ENTIRE FCST AREA.

.RNK...
NC...NONE.
VA...NONE.
WV...NONE.

11

Hazardous weather outlook, Aug 5, 6:32 AM EDT, 8 hours 16 minutes before

NCZ001>006-018>020-VAZ007-009>020-022>024-032>035-043>047-058-059-
WVZ042>045-061000-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BLACKSBURG VA
632 AM EDT TUE AUG 5 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST WEST VIRGINIA...
WESTERN AND CENTRAL VIRGINIA...AS WELL AS NORTHWEST NORTH CAROLINA.

.DAY ONE...TODAY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING IN THE FOOTHILLS AND PIEDMONT OF NORTHWEST NORTH
CAROLINA...AND SOUTHWEST VIRGINIA. THE THREAT OF SEVERE
THUNDERSTORMS ALSO INCLUDES THE SOUTHERN SHENANDOAH VALLEY AND
ALLEGHANY HIGHLANDS OF VIRGINIA...AND THE GREENBRIER VALLEY OF
SOUTHEAST WEST VIRGINIA.  THE PRIMARY THREAT IS LARGE HAIL...BUT
ISOLATED DAMAGING WIND GUSTS ARE POSSIBLE. IN ADDITION...SCATTERED
AREAS WILL SEE BRIEF HEAVY RAINFALL OF 1 TO 2 INCHES. PLEASE SEE THE
LATEST SEVERE WEATHER OUTLOOK...SPSRNK...FOR DETAILS.

THIS PRODUCT CAN BE VIEWED ON THE BLACKSBURG OFFICE INTERNET PAGE AT
WWW.ERH.NOAA.GOV/ER/RNK.

.DAYS TWO THROUGH SEVEN...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON.

06

In the hours before

Local storm report, Aug 5, 10:22 AM EDT, 4 hours 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
1022 AM EDT TUE AUG 05 2003

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1220 AM    PATRICK SPRINGS           VA   60 MPH TSTM GUST
08/05/03   PATRICK                        LARGE TREE BLOWN DOWN
                                          ACROSS POWERLINE.REPORTED
                                          BY PATRICK COUNTY 911.

1230 AM    MONROE                    VA   60 MPH TSTM GUST
08/05/03   AMHERST                        LARGE TREE BLOWN DOWN
                                          ACROSS ROAD.REPORTED BY
                                          AMHERST SHERIFFS OFFICE.

Special weather statement, Aug 5, 1:00 PM EDT, 1 hour 48 minutes before

NCZ003>006-019-020-VAZ018>020-022>024-032>035-043>047-058-059-WVZ044-
045-052000-
SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BLACKSBURG VA
100 PM EDT TUE AUG 5 2003

...SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING...

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING MAINLY ALONG AND EAST OF THE BLUE RIDGE.

THE VIRGINIA FOOTHILLS...INTO THE PIEDMONT OF NORTH CAROLINA IS
EXPECTED TO BECOME MODERATELY UNSTABLE THIS AFTERNOON.  SCATTERED
THUNDERSTORMS WILL DEVELOP AS AN UPPER LEVEL DISTURBANCE SWEEPS
ACROSS THE REGION DURING THE LATE AFTERNOON. SOME OF THESE STORMS
WILL HAVE THE CAPABILITY TO BECOME SEVERE PRODUCING PENNY SIZE OR
LARGER HAIL AND ISOLATED WIND GUSTS TO 60 MPH.

SKYWARN SPOTTER ACTIVATION MAY BE REQUIRED LATE THIS AFTERNOON OR
THIS EVENING.

STAY TUNED TO NOAA WEATHER RADIO AND OTHER LOCAL MEDIA FOR FURTHER
DETAILS OR UPDATES.

11

Local storm report, Aug 5, 1:13 PM EDT, 1 hour 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
0113 PM EDT TUE AUG 05 2003

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0105 AM    5 N ROANOKE               VA   F1 TORNADO
08/05/03   ROANOKE                        A BRIEF TORNADO DEVELOPED
                                          AROUND 105 AM ABOUT 5 MILES
                                          NORTH OF ROANOKE. THE
                                          TORNADO WAS ON THE GROUND
                                          FOR APPROXIMATELY 1/2 MILE
                                          AND WAS BETWEEN 15 AND 35
                                          YARDS WIDE. THE TORNADO
                                          ROLLED A VEHICLE 50 TO 75
                                          FEET, BLEW IN PLATE GLASS
                                          WINDOWS AND GLASS DOORS,
                                          AND LIFTED A GOOD PORTION
                                          OF THE ROOF OFF A BUSINESS,
                                          AND RIPPED SHINGLES OFF A
                                          FEW HOMES. INFORMATION
                                          PROVIDED BY ROANOKE COUNTY
                                          EMERGENCY MANAGER.

EMLAW

Local storm report, Aug 5, 2:45 PM EDT, 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
245 PM EDT TUE AUG 05 2003

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0243 PM    CATAWBA                   VA   1.00 IN HAIL
08/05/03   ROANOKE                        REPORTED BY SPOTTER.

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 4, 10:05 PM EDT	Severe Thunderstorm Warning	RNK	Franklin	25 min
Aug 4, 10:21 PM EDT	Flash Flood Warning	RNK	Tazewell	3 hr
Aug 4, 11:47 PM EDT	Severe Thunderstorm Warning	RNK	Bedford, Campbell, City of Lynchburg	28 min
Aug 5, 12:06 AM EDT	Severe Thunderstorm Warning	RNK	Amherst, Rockbridge, City of Buena Vista, City of Lexington	39 min
Aug 5, 12:13 AM EDT	Severe Thunderstorm Warning	RNK	Patrick	32 min
Aug 5, 1:01 PM EDT	Severe Thunderstorm Warning	RNK	Bedford, Franklin	59 min
Aug 5, 2:33 PM EDT	Severe Thunderstorm Warning	RNK	Craig, Montgomery, City of Radford	57 min
Aug 5, 2:34 PM EDT	Severe Thunderstorm Warning	RNK	Montgomery, City of Radford	56 min
Aug 5, 2:39 PM EDT	Severe Thunderstorm Warning	RNK	Roanoke	36 min
Aug 5, 3:21 PM EDT	Severe Thunderstorm Warning	RNK	Floyd	24 min
Aug 5, 3:39 PM EDT	Severe Thunderstorm Warning	RNK	Roanoke, City of Roanoke, City of Salem	51 min
Aug 5, 3:54 PM EDT	Severe Thunderstorm Warning	RNK	Bedford	66 min
Aug 5, 4:43 PM EDT	Severe Thunderstorm Warning	RNK	Franklin	62 min
Aug 5, 6:22 PM EDT	Severe Thunderstorm Warning	RNK	Halifax	23 min
Aug 5, 6:23 PM EDT	Severe Thunderstorm Warning	RNK	Halifax	52 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2003 Every severe thunderstorm warning in 2003

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.