Alert archive / Virginia / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 171, NWS Blacksburg, VA

July 31, 2019Alleghany County, Botetourt County, Virginia

NWS Blacksburg, VA issued this severe thunderstorm warning at Jul 31, 2019, 6:02 PM EDT for Alleghany County, Botetourt County, Virginia. It was in force for 33 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 31, 2019, 6:02 PM EDT (22:02 UTC)
Expired: Jul 31, 2019, 6:35 PM EDT
In force: 33 min
Issued by: NWS Blacksburg, VA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Alleghany County, VA, Botetourt County, VA

The radar

The Roanoke radar (KFCX), 79 km from the middle of the area, began a volume at 22:04 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

Roanoke, VA (KRNK), launched 12:00Z, 10.0 hours before the alert went out and 64 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: 7 J/kg
Mixed-layer CIN: -188 J/kg
Mixed-layer LCL: 1412 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: -5 m²/s²
0-3 km storm-relative helicity: 9 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 Blacksburg, VA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 31, 3:45 PM EDT, 2 hours 17 minutes earlier.

Area forecast discussion, Jul 31, 3:45 PM EDT, 2 hours 17 minutes before

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Hazardous weather outlook, Jul 31, 3:51 PM EDT, 2 hours 11 minutes before

Hazardous Weather Outlook
National Weather Service Blacksburg VA
351 PM EDT Wed Jul 31 2019

NCZ001>006-018>020-VAZ007-009>020-022>024-032>035-043>047-058-059-
WVZ042>044-507-508-011100-
Ashe-Alleghany NC-Surry-Stokes-Rockingham-Caswell-Watauga-Wilkes-
Yadkin-Tazewell-Smyth-Bland-Giles-Wythe-Pulaski-Montgomery-Grayson-
Carroll-Floyd-Craig-Alleghany VA-Bath-Roanoke-Botetourt-Rockbridge-
Patrick-Franklin-Bedford-Amherst-Henry-Pittsylvania-Campbell-
Appomattox-Buckingham-Halifax-Charlotte-Mercer-Summers-Monroe-
Eastern Greenbrier-Western Greenbrier-
351 PM EDT Wed Jul 31 2019

This Hazardous Weather Outlook is for north central North Carolina,
northwest North Carolina, central Virginia, south central Virginia,
southwest Virginia, west central Virginia and southeast West
Virginia.

.DAY ONE...This afternoon and tonight.

Isolated to scattered strong to severe thunderstorms will be possible
this evening until around sunset. Damaging wind gusts and localized
flooding will be the main hazards. Marginally severe hail will also
be possible in the strongest storms.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Scattered to numerous showers and thunderstorms are expected each
day, decreasing slightly during the weekend and early next week. The
main concern will be locally heavy rainfall and repeated rainfall
from day-to-day resulting in localized flooding. A few storms could
also be severe at times.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed at times through the period
primarily to help identify wind damage and areas of flooding.

RAB

In the hours before

Special weather statement, Jul 31, 5:17 PM EDT, 45 minutes before

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Special weather statement, Jul 31, 5:39 PM EDT, 23 minutes before

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Special weather statement, Jul 31, 5:46 PM EDT, 16 minutes before

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Special weather statement, Jul 31, 5:50 PM EDT, 12 minutes before

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Local storm report, Jul 31, 5:56 PM EDT, 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BLACKSBURG VA
556 PM EDT WED JUL 31 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0519 PM     TSTM WND DMG     1 SE BLUE RIDGE         37.38N 79.81W
07/31/2019                   BOTETOURT          VA   PUBLIC

            SEVERAL LARGE BRANCHES SNAPPED OFF OF TREES
            ALONG THE BLUE RIDGE PARKWAY. TIME ESTIMATED
            WITH RADAR.

&&

VFJ

Special weather statement, Jul 31, 5:57 PM EDT, 5 minutes before

Special Weather Statement
National Weather Service BLACKSBURG VA
557 PM EDT Wed Jul 31 2019

VAZ035-312230-
Amherst-
557 PM EDT Wed Jul 31 2019

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN AMHERST COUNTY...

Until 630 PM EDT.

At 556 PM EDT, a strong thunderstorm was located over Amherst, moving
northeast at 20 mph.

Winds in excess of 40 mph and pea size hail are possible with this
storm.

Locations impacted include...
Amherst...
Clifford...
Falconerville...
New Glasgow...
and Piney River.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3751 7910 3760 7916 3771 7904 3770 7903
      3771 7902 3770 7901 3770 7899 3768 7898
      3768 7897 3767 7897 3755 7890 3755 7888
      3754 7887
TIME...MOT...LOC 2156Z 236DEG 17KT 3760 7905

RS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 12:33 PM EDT	Special Weather Statement	RNK	Grayson	57 min
Jul 31, 1:25 PM EDT	Severe Thunderstorm Warning	RNK	Grayson, Smyth	25 min
Jul 31, 1:57 PM EDT	Special Weather Statement	RNK	Bath	63 min
Jul 31, 2:25 PM EDT	Special Weather Statement	RNK	Giles, City of Radford	50 min
Jul 31, 2:36 PM EDT	Special Weather Statement	RNK	Craig	39 min
Jul 31, 2:41 PM EDT	Severe Thunderstorm Warning	RNK	Bath, Rockbridge	22 min
Jul 31, 2:49 PM EDT	Special Weather Statement	RNK	Grayson	41 min
Jul 31, 3:00 PM EDT	Severe Thunderstorm Warning	RNK	Giles, Pulaski	45 min
Jul 31, 3:16 PM EDT	Severe Thunderstorm Warning	RNK	Grayson	59 min
Jul 31, 3:34 PM EDT	Severe Thunderstorm Warning	RNK	Rockbridge	26 min
Jul 31, 3:38 PM EDT	Severe Thunderstorm Warning	RNK	Alleghany, Bath, Botetourt, Rockbridge, City of Lexington	67 min
Jul 31, 4:05 PM EDT	Special Weather Statement	RNK	Floyd	25 min
Jul 31, 4:21 PM EDT	Severe Thunderstorm Warning	RNK	Bedford, Botetourt, Rockbridge	39 min
Jul 31, 4:48 PM EDT	Special Weather Statement	RNK	Floyd	57 min
Jul 31, 4:52 PM EDT	Severe Thunderstorm Warning	RNK	Amherst, Bedford, Botetourt, Rockbridge, City of Buena Vista	53 min
Jul 31, 4:58 PM EDT	Special Weather Statement	RNK	Floyd	47 min
Jul 31, 5:01 PM EDT	Severe Thunderstorm Warning	RNK	Bedford, Botetourt, Roanoke	59 min
Jul 31, 5:05 PM EDT	Special Weather Statement	RNK	Alleghany	25 min
Jul 31, 5:17 PM EDT	Special Weather Statement	RNK	Smyth, Tazewell	58 min
Jul 31, 5:39 PM EDT	Special Weather Statement	RNK	Alleghany, City of Covington	66 min
Jul 31, 5:46 PM EDT	Special Weather Statement	RNK	Pulaski, City of Radford	44 min
Jul 31, 5:50 PM EDT	Special Weather Statement	RNK	City of Martinsville	25 min
Jul 31, 5:57 PM EDT	Special Weather Statement	RNK	Amherst	33 min
Jul 31, 6:07 PM EDT	Special Weather Statement	RNK	Buckingham	53 min
Jul 31, 6:25 PM EDT	Special Weather Statement	RNK	Pittsylvania	35 min
Jul 31, 6:30 PM EDT	Severe Thunderstorm Warning	RNK	Halifax, Pittsylvania	60 min
Jul 31, 7:33 PM EDT	Flash Flood Warning	RNK	Halifax, Pittsylvania	4 hr
Jul 31, 7:42 PM EDT	Special Weather Statement	RNK	Halifax	33 min
Jul 31, 1:50 PM EDT	Areal Flood Advisory	RNK	Watauga	26 min
Jul 31, 2:17 PM EDT	Special Weather Statement	RNK	Ashe	28 min
Jul 31, 2:20 PM EDT	Severe Thunderstorm Warning	RNK	Ashe, Watauga, Wilkes	55 min
Jul 31, 3:24 PM EDT	Special Weather Statement	RNK	Yadkin	36 min
Jul 31, 3:50 PM EDT	Special Weather Statement	RNK	Caswell	25 min
Jul 31, 3:56 PM EDT	Severe Thunderstorm Warning	RNK	Surry, Wilkes	49 min
Jul 31, 6:19 PM EDT	Special Weather Statement	RNK	Caswell	26 min
Jul 31, 6:56 PM EDT	Special Weather Statement	RNK	Caswell	34 min
Jul 31, 4:16 PM EDT	Special Weather Statement	RNK	Monroe, Summers	59 min
Jul 31, 6:33 PM EDT	Severe Thunderstorm Warning	RNK	Mercer	24 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2019 Every severe thunderstorm warning in 2019

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.