Alert archive / Virginia / Mesoscale Discussions in 2021
Mesoscale Discussion 896
The Storm Prediction Center issued this mesoscale discussion at Jun 9, 2021, 1:44 PM EDT for 28 counties in North Carolina; 45 counties in Virginia. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 9, 2021, 1:44 PM EDT (17:44 UTC)
- Expired
- Jun 9, 2021, 3:45 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 73 counties
Beaufort County, NC, Bertie County, NC, Camden County, NC, Chowan County, NC, Craven County, NC, Currituck County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Granville County, NC, Greene County, NC, Halifax County, NC, Hertford County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Northampton County, NC, Pasquotank County, NC, Perquimans County, NC, Person County, NC, Pitt County, NC, Tyrrell County, NC, Vance County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Albemarle County, VA, Amelia County, VA, Appomattox County, VA, Brunswick County, VA, Buckingham County, VA, Campbell County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Charlottesville, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Portsmouth, VA, City of Richmond, VA, City of Suffolk, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Fluvanna County, VA, Goochland County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, Louisa County, VA, Lunenburg County, VA, Mecklenburg County, VA, New Kent County, VA, Nottoway County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA
The radar
The Norfolk radar (KAKQ), 84 km from the middle of the area, began a volume at 17:44 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, 5.7 hours before the alert went out and 171 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
- 92 J/kg
- Mixed-layer CIN
- -99 J/kg
- Mixed-layer LCL
- 1085 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- -24 m²/s²
- 0-3 km storm-relative helicity
- 42 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
649
ACUS11 KWNS 091744
SWOMCD
SPC MCD 091744
NCZ000-VAZ000-091945-
Mesoscale Discussion 0896
NWS Storm Prediction Center Norman OK
1244 PM CDT Wed Jun 09 2021
Areas affected...Southeastern Virginia into eastern North Carolina
Concerning...Severe potential...Watch unlikely
Valid 091744Z - 091945Z
Probability of Watch Issuance...20 percent
SUMMARY...Locally damaging winds will be possible with water-loaded
downdrafts this afternoon. Some potential exists for greater
organization as cold pools merge. No WW is anticipated, but trends
in storm organization will be monitored.
DISCUSSION...Thunderstorms have developed along the Blue Ridge in
central Virginia. These storms are expected to slowly drift
southeastward into a hot and very moist airmass. Dewpoints in the
low 70s F and temperatures that may near 90 F will support moderate
buoyancy of 2000 to perhaps greater than 2500 J/kg MLCAPE. This
morning's observed soundings at WAL and MHX sampled 6-7 C/km lapse
rates. Storm intensification will not be overly quick given the
modest lapse rates and rather weak flow aloft. However, locally
intense water-loaded downdrafts are possible with an attendant
threat for damaging winds. Storm coverage may also be sufficient for
a small cluster or two to develop later this afternoon. Should this
occur, the threat for damaging winds would be locally greater ahead
of the clusters. A WW is not anticipated this afternoon, but trends
will be monitored for greater cold-pool-related organization.
..Wendt/Guyer.. 06/09/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...
LAT...LON 36617926 37567902 38117860 38257792 37227639 36337572
35577593 34997699 35027783 35637847 36617926Nearby
Mesoscale Discussions in Virginia, 2021Mesoscale Discussions in North Carolina, 2021Every mesoscale discussion 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.