Alert archive / Virginia / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 235
The Storm Prediction Center issued this severe thunderstorm watch at Jun 4, 2021, 12:59 PM EDT for 6 counties in Maryland; 6 counties in North Carolina; 51 counties in Virginia. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 4, 2021, 12:59 PM EDT (16:59 UTC)
- Expired
- Jun 4, 2021, 8:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 55 kt
All 63 counties
Calvert County, MD, Charles County, MD, Dorchester County, MD, Saint Mary's County, MD, Somerset County, MD, Wicomico County, MD, Camden County, NC, Chowan County, NC, Currituck County, NC, Gates County, NC, Pasquotank County, NC, Perquimans County, NC, Accomack County, VA, Amelia County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Franklin, VA, City of Fredericksburg, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Richmond, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fluvanna County, VA, Gloucester County, VA, Goochland 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, Louisa County, VA, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Orange County, VA, Powhatan County, VA, Prince George County, VA, Richmond County, VA, Southampton County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA
The radar
The Norfolk radar (KAKQ), 82 km from the middle of the area, began a volume at 17:00 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 4, 1:10 PM EDT | Severe Thunderstorm Warning | LWX | Orange, Spotsylvania, City of Fredericksburg | 36 min |
| Jun 4, 1:36 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Prince George's, Saint Mary's | 39 min |
| Jun 4, 2:17 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Saint Mary's | 43 min |
| Jun 4, 2:50 PM EDT | Severe Thunderstorm Warning | LWX | Calvert, Charles, Saint Mary's | 40 min |
| Jun 4, 2:55 PM EDT | Severe Thunderstorm Warning | AKQ | Dorchester | 30 min |
| Jun 4, 3:18 PM EDT | Severe Thunderstorm Warning | AKQ | Essex, Northumberland, Richmond, Westmoreland | 42 min |
| Jun 4, 3:19 PM EDT | Severe Thunderstorm Warning | LWX | Saint Mary's | 41 min |
| Jun 4, 3:54 PM EDT | Severe Thunderstorm Warning | LWX | Saint Mary's | 51 min |
| Jun 4, 3:59 PM EDT | Severe Thunderstorm Warning | AKQ | Essex, Lancaster, Northumberland, Richmond, Westmoreland | 61 min |
| Jun 4, 5:59 PM EDT | Severe Thunderstorm Warning | AKQ | Isle of Wight, James City, Surry, York, City of Hampton, City of Newport News and 1 more | 61 min |
| Jun 4, 7:16 PM EDT | Flash Flood Warning | AKQ | Isle of Wight | 3 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 5.0 hours before the alert went out and 141 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.
- Mixed-layer CAPE
- 381 J/kg
- Mixed-layer CIN
- -55 J/kg
- Mixed-layer LCL
- 947 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- -8 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.1
The text
As transmitted.
622 WWUS20 KWNS 041657 SEL5 SPC WW 041657 MDZ000-NCZ000-VAZ000-CWZ000-050100- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 235 NWS Storm Prediction Center Norman OK 100 PM EDT Fri Jun 4 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern Maryland Northeast North Carolina East/Southeast Virginia Coastal Waters * Effective this Friday afternoon and evening from 100 PM until 900 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible SUMMARY...Clusters of storms will move east-southeastward across the region this afternoon with the strongest storms capable of wind damage. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 45 miles west northwest of Richmond VA to 45 miles east northeast of Norfolk VA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 29025. ...Guyer
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 4, 12:46 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Calvert, Charles, Prince George's, Queen Anne's, Saint Mary's and 2 more | 59 min |
| Jun 4, 2:26 PM EDT | Mesoscale Discussion | SPC | Cecil, Harford | 94 min |
| Jun 4, 4:12 PM EDT | Mesoscale Discussion | SPC | Calvert, Caroline, Cecil, Dorchester, Harford, Kent and 6 more | 93 min |
Nearby
Severe Thunderstorm Watches in Virginia, 2021Severe Thunderstorm Watches in Maryland, 2021Severe Thunderstorm Watches in North Carolina, 2021Every severe thunderstorm watch in 2021
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.