Alert archive / North Carolina / Hurricane Warnings in 2011

Hurricane Warning 1009, NWS NHC

August 21, 201115 counties in North Carolina; 9 counties in Virginia

NWS NHC issued this hurricane warning at Aug 21, 2011, 11:00 AM EDT for 15 counties in North Carolina; 9 counties in Virginia. It was in force for 7 days. 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 21, 2011, 11:00 AM EDT (15:00 UTC)
Expired
Aug 28, 2011, 10:53 AM EDT
In force
7 days
Issued by
NWS NHC
All 24 counties

Beaufort County, NC, Bertie County, NC, Brunswick County, NC, Camden County, NC, Chowan County, NC, Currituck County, NC, Dare County, NC, Hyde County, NC, New Hanover County, NC, Pamlico County, NC, Pasquotank County, NC, Pender County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC, Accomack County, VA, City of Chesapeake, VA, City of Virginia Beach, VA, Gloucester County, VA, Lancaster County, VA, Mathews County, VA, Middlesex County, VA, Northampton County, VA, Northumberland County, VA

The radar

The Norfolk radar (KAKQ), 92 km from the middle of the area, began a volume at 15:05 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

Newport, NC (KMHX), launched 12:00Z, 3.0 hours before the alert went out and 167 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 12:00Z on 2011-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1537 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, Newport, NC at 12:00Z on 2011-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 square meters per square second.193958Sfc1 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
1537 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
811 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS NHC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 5:00 AM EDTHurricane WatchNHC5 days

Nearby

Hurricane Warnings in North Carolina, 2011Hurricane Warnings in Virginia, 2011Hurricane Warnings in Puerto Rico, 2011Every hurricane warning in 2011

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.