Alert archive / Virginia / Mesoscale Discussions in 2017
Mesoscale Discussion 1789
The Storm Prediction Center issued this mesoscale discussion at Dec 8, 2017, 2:52 PM EST for Sussex County, Delaware; 5 counties in Maryland; 33 counties in Virginia. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 8, 2017, 2:52 PM EST (19:52 UTC)
- Expired
- Dec 8, 2017, 7:45 PM EST
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 39 counties
Sussex County, DE, Dorchester County, MD, Saint Mary's County, MD, Somerset County, MD, Wicomico County, MD, Worcester County, MD, Accomack County, VA, Amelia County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Hopewell, VA, City of Petersburg, VA, City of Richmond, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Gloucester County, VA, Goochland County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, James City County, VA, King and Queen County, VA, King William County, VA, Lancaster County, VA, Lunenburg County, VA, Mecklenburg County, VA, Middlesex County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Richmond County, VA, Westmoreland County, VA
The radar
The Norfolk radar (KAKQ), 76 km from the middle of the area, began a volume at 19:52 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.9 hours before the alert went out and 157 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1723 m above ground
- 0-6 km bulk shear
- 96 kt
- 0-1 km storm-relative helicity
- 44 m²/s²
- 0-3 km storm-relative helicity
- 179 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 8, 12:06 PM EST | Mesoscale Discussion | SPC | Carroll, Grayson, Henry, Patrick, City of Galax, City of Martinsville | 4 hr |
Nearby
Mesoscale Discussions in Virginia, 2017Mesoscale Discussions in Maryland, 2017Mesoscale Discussions in Delaware, 2017Every mesoscale discussion 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.