Alert archive / South Carolina / Mesoscale Discussions in 2012
Mesoscale Discussion 2015
The Storm Prediction Center issued this mesoscale discussion at Oct 1, 2012, 3:20 PM EDT for Brunswick County, Columbus County, New Hanover County, North Carolina; 7 counties in South Carolina. It was in force for 85 min.
The area
The outline as issued.
The facts
- Issued
- Oct 1, 2012, 3:20 PM EDT (19:20 UTC)
- Expired
- Oct 1, 2012, 4:45 PM EDT
- In force
- 85 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
Counties Brunswick County, NC, Columbus County, NC, New Hanover County, NC, Clarendon County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Sumter County, SC, Williamsburg County, SC
The radar
The Wilmington radar (KLTX), 48 km from the middle of the area, began a volume at 19:23 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
Charleston AFB, SC (KCHS), launched 12:00Z, 7.3 hours before the alert went out and 147 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
- 1483 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 464 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 153 m²/s²
- 0-3 km storm-relative helicity
- 185 m²/s²
- Significant tornado parameter
- 0.9
- Supercell composite
- 6.1
The text
As transmitted, in the capitals the NWS used until 2016.
499
ACUS11 KWNS 011921
SWOMCD
SPC MCD 011920
NCZ000-SCZ000-012045-
MESOSCALE DISCUSSION 2015
NWS STORM PREDICTION CENTER NORMAN OK
0220 PM CDT MON OCT 01 2012
AREAS AFFECTED...ERN SC/FAR SERN NC
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 011920Z - 012045Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...AN ISOLATED TORNADO OR TWO IS POSSIBLE ACROSS PARTS OF
NERN SC/SERN NC NEAR THE SURFACE WARM FRONT. WW IS NOT ANTICIPATED
HOWEVER DUE TO GEOGRAPHICALLY LIMITED THREAT AREA.
DISCUSSION...SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED ACROSS
PORTIONS OF NERN SC AND ADJACENT AREAS JUST OFFSHORE...ALONG A
SURFACE WARM FRONT WHERE MODEST DESTABILIZATION HAS OCCURRED. WHILE
LOW-LEVEL FLOW OFF THE SURFACE REMAINS MODEST IN THIS
REGION...BACKED/ELY SURFACE WINDS N OF THE WARM FRONT ARE PROVIDING
A NARROW CORRIDOR OF ENHANCED LOW-LEVEL SHEAR -- SUPPORTIVE OF
UPDRAFT ROTATION. THOUGH THE MUCH MORE STABLE BOUNDARY LAYER TO THE
COOL SIDE OF THE FRONT WILL LIMIT NWD POTENTIAL OF ANY TORNADO
THREAT...A NARROW ZONE OF HEIGHTENED POTENTIAL EXISTS IMMEDIATELY N
OF THE FRONT. IN THIS ZONE...RADAR IMAGERY REVEALS A
PERSISTENT/ROTATING CELL OVER HORRY COUNTY SC...WHICH HAS PRODUCED A
TORNADO IN THE PAST HALF HOUR. ADDITIONAL BRIEF TORNADIC ACTIVITY
REMAINS POSSIBLE WITH THIS STORM AS IT SHIFTS NEWD TOWARD THE NC
BORDER.
MEANWHILE...THOUGH ANOTHER CELL OR TWO MAY EVOLVE AND ACQUIRE
LOW-LEVEL ROTATION WITHIN THIS SAME SMALL ZONE OF FAVORABLE
BACKGROUND CONDITIONS...OVERALL THREAT WHICH IS EXPECTED TO REMAIN
LIMITED IN BOTH DEGREE AND COVERAGE SUGGESTS THAT WW ISSUANCE WILL
LIKELY NOT BECOME NECESSARY.
..GOSS/HART.. 10/01/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...ILM...CHS...CAE...
LAT...LON 34417717 33527794 33367919 33138037 33578094 34158004
34517867 34417717Nearby
Mesoscale Discussions in South Carolina, 2012Mesoscale Discussions in North Carolina, 2012Every mesoscale discussion in 2012
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.