Alert archive / Virginia / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 172, NWS Wakefield, VA

August 18, 20176 counties in Virginia

NWS Wakefield, VA issued this severe thunderstorm warning at Aug 18, 2017, 7:53 PM EDT for 6 counties in Virginia. It was in force for 52 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
Aug 18, 2017, 7:53 PM EDT (23:53 UTC)
Expired
Aug 18, 2017, 8:45 PM EDT
In force
52 min
Issued by
NWS Wakefield, VA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Essex County, VA, King and Queen County, VA, Lancaster County, VA, Northumberland County, VA, Richmond County, VA, Westmoreland County, VA

The radar

The Norfolk radar (KAKQ), 103 km from the middle of the area, began a volume at 23:55 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 18, 2:27 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 11.9 hours before the alert went out and 115 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, Wallops Is Stn, VA at 12:00Z on 2017-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 582 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, Wallops Is Stn, VA at 12:00Z on 2017-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 105 square meters per square second.1939Sfc1 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
582 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
808 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
105 m²/s²
0-3 km storm-relative helicity
112 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 Wakefield, VA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 7:25 PM EDT, 28 minutes earlier.

Area forecast discussion, Aug 18, 7:25 PM EDT, 28 minutes before
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Hazardous weather outlook, Aug 18, 2:37 PM EDT, 5 hours 16 minutes before
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In the hours before

Special weather statement, Aug 18, 6:37 PM EDT, 1 hour 16 minutes before
Special Weather Statement
National Weather Service Wakefield VA
637 PM EDT FRI AUG 18 2017

VAZ062-064-075-510-511-521-182330-
Goochland-Western Hanover-Westmoreland-Western Essex-Caroline-Eastern
Louisa-
637 PM EDT FRI AUG 18 2017

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT EASTERN LOUISA...
NORTHWESTERN GOOCHLAND...CAROLINE...NORTHWESTERN WESTMORELAND...
NORTHWESTERN HANOVER AND NORTHWESTERN ESSEX COUNTIES...

At 637 PM EDT, radar indicated strong thunderstorms were located
along a line extending from near Massaponax to near Gum Spring.
Movement was northeast at 35 mph.

Wind gusts in excess of 30 mph and rainfall amounts of up to 1 inch
are possible with these storms.

Locations impacted include...
Colonial Beach, Bowling Green, Mineral, Hadensville, Milford, Port
Royal, Gum Spring, Ladysmith, Bumpass, Kings Dominion, Montpelier,
Fort A.p. Hill, Chilesburg, Orchid, Golansville, Potomac Beach,
Guinea, Corbin, Gum Tree and Supply.

Motorists should use extra caution in the vicinity of these storms.
Be prepared for rapid changes in weather and road conditions. Heavy
rain could cause ponding of water on roads...and possible minor
flooding of ditches and poor drainage areas.

LAT...LON 3826 7696 3821 7696 3820 7699 3820 7694
      3781 7740 3774 7814 3810 7785 3805 7775
      3802 7775 3799 7764 3825 7737 3822 7728
      3825 7727 3825 7723 3823 7725 3819 7725
      3820 7722 3814 7708 3826 7705 3828 7698
TIME...MOT...LOC 2237Z 245DEG 30KT 3820 7740 3781 7792

DEROSA
Special weather statement, Aug 18, 6:39 PM EDT, 1 hour 14 minutes before
Special Weather Statement
National Weather Service Wakefield VA
639 PM EDT FRI AUG 18 2017

VAZ061-062-068-069-511-513-515-182345-
Goochland-Western Chesterfield-Western Henrico (Including the City of
Richmond)-Western Hanover-Powhatan-Amelia-Cumberland-
639 PM EDT FRI AUG 18 2017

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHWESTERN
CHESTERFIELD...EASTERN CUMBERLAND...GOOCHLAND...NORTHWESTERN
HENRICO...WEST CENTRAL HANOVER...NORTHWESTERN AMELIA AND POWHATAN
COUNTIES AND THE CITY OF RICHMOND...

At 639 PM EDT, radar indicated strong thunderstorms were located
along a line extending from near Montpelier to near Jetersville.
Movement was northeast at 30 mph.

Wind gusts in excess of 40 mph and rainfall amounts of up to 1 inch
are possible with these storms.

Locations impacted include...
Richmond, Powhatan, Goochland, Ashland, Randolph Macon College,
Tuckahoe, Moseley, Amelia Courthouse, Bon Air, University Of
Richmond, Hanover, Oilville, Manakin, Tobaccoville, Trenholm, Morven,
Macon, Sabot, Laurel and Wyndham.

Strong wind gusts are possible with these storms. These wind gusts
are capable of knocking down tree limbs...small or weakened trees...
and blowing around trash cans...potted plants...lawn furniture and
other light outdoor objects.

Motorists should use extra caution in the vicinity of these storms.
Be prepared for rapid changes in weather and road conditions. Heavy
rain could cause ponding of water on roads...and possible minor
flooding of ditches and poor drainage areas.

LAT...LON 3775 7811 3777 7790 3773 7780 3778 7777
      3782 7741 3781 7742 3780 7739 3779 7739
      3778 7740 3778 7737 3776 7737 3737 7767
      3728 7818 3730 7823 3736 7824
TIME...MOT...LOC 2239Z 240DEG 26KT 3777 7774 3731 7818

DEROSA
Special weather statement, Aug 18, 7:08 PM EDT, 45 minutes before
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Special weather statement, Aug 18, 7:21 PM EDT, 32 minutes before
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Special weather statement, Aug 18, 7:30 PM EDT, 23 minutes before
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Local storm report, Aug 18, 7:45 PM EDT, 8 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 11:20 AM EDTHeat AdvisoryAKQGloucester, James City, Surry, York, City of Chesapeake, City of Hampton and 4 more9 hr
Aug 18, 3:38 PM EDTSpecial Weather StatementAKQCity of Virginia Beach37 min
Aug 18, 4:23 PM EDTSpecial Marine WarningAKQ52 min
Aug 18, 4:47 PM EDTSpecial Marine WarningAKQ43 min
Aug 18, 6:01 PM EDTSpecial Weather StatementAKQPrince Edward44 min
Aug 18, 6:37 PM EDTSpecial Weather StatementAKQCaroline53 min
Aug 18, 6:39 PM EDTSpecial Weather StatementAKQAmelia, Goochland, Hanover, Powhatan66 min
Aug 18, 7:08 PM EDTSpecial Weather StatementAKQCaroline, Westmoreland67 min
Aug 18, 7:13 PM EDTSevere Thunderstorm WarningAKQCaroline, Essex, Hanover, King and Queen, Richmond, Westmoreland47 min
Aug 18, 7:30 PM EDTSpecial Weather StatementAKQChesterfield, Essex, Hanover, Henrico, King William, City of Richmond60 min
Aug 18, 7:58 PM EDTSevere Thunderstorm WarningAKQEssex, Gloucester, Hanover, Henrico, King and Queen, King William and 5 more62 min
Aug 18, 4:18 PM EDTSpecial Weather StatementAKQBertie42 min
Aug 18, 2:19 PM EDTSpecial Weather StatementAKQWorcester41 min
Aug 18, 3:11 PM EDTSpecial Weather StatementAKQWorcester49 min
Aug 18, 3:59 PM EDTCoastal Flood AdvisoryAKQDorchester, Somerset, Wicomico10 hr
Aug 18, 7:21 PM EDTSpecial Weather StatementAKQDorchester39 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2017Every severe thunderstorm warning in 2017

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.