Alert archive / Virginia / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 13, NWS Blacksburg, VA

May 18, 2001Halifax County, Virginia

NWS Blacksburg, VA issued this severe thunderstorm warning at May 18, 2001, 8:12 PM EDT for Halifax County, Virginia. It was in force for 33 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: May 18, 2001, 8:12 PM EDT (00:12 UTC)
Expired: May 18, 2001, 8:45 PM EDT
In force: 33 min
Issued by: NWS Blacksburg, VA
Area: Whole counties

County Halifax County, VA

The radar

The Roanoke radar (KFCX), 122 km from the middle of the area, began a volume at 00:16 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

Time	Report	Where	Remark
May 18, 8:25 PM EDT	Hail 0.75	South Boston, VA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 0.2 hours before the alert went out and 69 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: 57 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 1928 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 30 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.

000 
WUUS51 KRNK 190009
SVRRNK

VAC083-190045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BLACKSBURG VA
812 PM EDT FRI MAY 18 2001

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN HALIFAX COUNTY IN SOUTH CENTRAL VIRGINIA...

* UNTIL 845 PM EDT.

* AT 810 PM EDT...RADAR AND SPOTTERS INDICATED A SEVERE THUNDERSTORM
  NEAR SOUTH BOSTON...MOVING SOUTHEAST AT 15 MPH.

HAIL UP TO AN INCH IN DIAMETER HAS BEEN REPORTED WITH THIS STORM....
ABOUT 5 MILES WEST NORTHWEST OF HALIFAX.

SOME LOCATIONS THREATENED THROUGH 845 PM EDT INCLUDE
  SOUTH BOSTON...
  VIRGILINA...

<<CALL TO ACTION>>IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE
WEATHER IN A STRONG BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY
RAIN...AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY.

.END
$$

04

The office that day

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

Issued	Product	Office	Counties	Lasted
May 19, 3:54 PM EDT	Flash Flood Warning	RNK	Giles	3 hr
May 19, 4:21 PM EDT	Severe Thunderstorm Warning	RNK	Campbell	39 min
May 19, 4:28 PM EDT	Severe Thunderstorm Warning	RNK	Floyd, Pulaski	47 min
May 19, 4:41 PM EDT	Severe Thunderstorm Warning	RNK	Halifax, Pittsylvania	49 min
May 19, 5:00 PM EDT	Severe Thunderstorm Warning	RNK	Giles	30 min
May 19, 5:27 PM EDT	Severe Thunderstorm Warning	RNK	Pittsylvania, City of Danville	48 min
May 19, 5:30 PM EDT	Severe Thunderstorm Warning	RNK	Halifax	45 min
May 19, 5:42 PM EDT	Severe Thunderstorm Warning	RNK	Franklin	33 min
May 19, 5:52 PM EDT	Flash Flood Warning	RNK	Halifax	113 min
May 19, 6:07 PM EDT	Severe Thunderstorm Warning	RNK	Henry, City of Martinsville	38 min
May 19, 6:41 PM EDT	Flash Flood Warning	RNK	Henry, City of Martinsville	2 hr

Nearby

Severe Thunderstorm Warnings in Virginia, 2001 Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.