Alert archive / Virginia / Tornado Watches in 2008

Tornado Watch 890

September 6, 20084 counties in Maryland; 21 counties in North Carolina; 25 counties in Virginia

The Storm Prediction Center issued this tornado watch at Sep 6, 2008, 4:45 AM EDT for 4 counties in Maryland; 21 counties in North Carolina; 25 counties in Virginia. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Sep 6, 2008, 4:45 AM EDT (08:45 UTC)
Expired
Sep 6, 2008, 1:00 PM EDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 50 counties

Dorchester County, MD, Somerset County, MD, Wicomico County, MD, Worcester County, MD, Beaufort County, NC, Bertie County, NC, Camden County, NC, Carteret County, NC, Chowan County, NC, Craven County, NC, Currituck County, NC, Dare County, NC, Edgecombe County, NC, Gates County, NC, Halifax County, NC, Hertford County, NC, Hyde County, NC, Martin County, NC, Northampton County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Pitt County, NC, Tyrrell County, NC, Washington County, NC, Accomack County, VA, City of Chesapeake, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Newport News, VA, City of Norfolk, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Gloucester County, VA, Greensville County, VA, Isle of Wight County, VA, James City County, VA, Lancaster County, VA, Mathews County, VA, Middlesex County, VA, Northampton County, VA, Northumberland County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA

The radar

The Norfolk radar (KAKQ), 89 km from the middle of the area, began a volume at 08:45 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
10%
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
40%

Warnings issued inside it

1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Sep 6, 4:53 AM EDTFlash Flood WarningRAHEdgecombe, Halifax, Nash, Wayne, Wilson6 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

Newport, NC (KMHX), launched 00:00Z, 8.8 hours before the alert went out and 261 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, Newport, NC at 00:00Z on 2008-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 948 joules per kilogram.LCLEL10008507005003002001001 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, Newport, NC at 00:00Z on 2008-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 152 square meters per square second.19395878Sfc1 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
948 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
664 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
152 m²/s²
0-3 km storm-relative helicity
185 m²/s²
Significant tornado parameter
0.7
Supercell composite
4.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 6, 4:22 AM EDTMesoscale DiscussionSPCFrederick3 hr
Sep 6, 8:40 AM EDTMesoscale DiscussionSPCDorchester, Somerset, Wicomico, Worcester2 hr
Sep 6, 11:09 AM EDTMesoscale DiscussionSPCCaroline, Dorchester, Somerset, Wicomico, Worcester66 min
Sep 5, 9:06 PM EDTMesoscale DiscussionSPCBeaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 35 more114 min
Sep 6, 3:33 AM EDTMesoscale DiscussionSPCBeaufort, Bertie, Camden, Carteret, Chowan, Craven and 21 more87 min

Nearby

Tornado Watches in Virginia, 2008Tornado Watches in North Carolina, 2008Tornado Watches in Maryland, 2008Every tornado watch in 2008

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.