Alert archive / North Carolina / Freeze Warnings in 2009

Freeze Warning 7, NWS Greenville-Spartanburg, SC

October 17, 200911 counties in North Carolina; Rabun County, Georgia

NWS Greenville-Spartanburg, SC issued this freeze warning at Oct 17, 2009, 4:09 AM EDT for 11 counties in North Carolina; Rabun County, Georgia. It took effect at Oct 18, 2009, 12:00 AM EDT. It was in force for 9 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Oct 17, 2009, 4:09 AM EDT (08:09 UTC)
In effect from
Oct 18, 2009, 12:00 AM EDT
Expired
Oct 18, 2009, 9:00 AM EDT
In force
9 hr
Issued by
NWS Greenville-Spartanburg, SC

Counties Rabun County, GA, Avery County, NC, Buncombe County, NC, Graham County, NC, Haywood County, NC, Jackson County, NC, Macon County, NC, Madison County, NC, Mitchell County, NC, Swain County, NC, Transylvania County, NC, Yancey County, NC

The radar

The Knoxville radar (KMRX), 84 km from the middle of the area, began a volume at 08:08 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

Nashville Metro, TN (KBNA), launched 00:00Z, 8.2 hours before the alert went out and 341 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, Nashville Metro, TN at 00:00Z on 2009-10-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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, Nashville Metro, TN at 00:00Z on 2009-10-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -27 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
7 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
535 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-27 m²/s²
0-3 km storm-relative helicity
16 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 17, 3:57 AM EDTWinter Weather AdvisoryGSPAvery, Graham, Haywood, Madison, Mitchell, Swain and 1 more24 hr
Oct 17, 4:09 AM EDTFreeze WatchGSPBurke, Caldwell, Henderson, McDowell24 hr

Nearby

Freeze Warnings in North Carolina, 2009Freeze Warnings in Georgia, 2009Every freeze warning in 2009

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.