Alert archive / North Carolina / Mesoscale Discussions in 2012
Mesoscale Discussion 1639
The Storm Prediction Center issued this mesoscale discussion at Jul 28, 2012, 7:28 PM EDT for 12 counties in North Carolina; 5 counties in South Carolina. It was in force for 32 min.
The area
The outline as issued.
The facts
- Issued
- Jul 28, 2012, 7:28 PM EDT (23:28 UTC)
- Expired
- Jul 28, 2012, 8:00 PM EDT
- In force
- 32 min
- Issued by
- the Storm Prediction Center
Counties Bladen County, NC, Brunswick County, NC, Carteret County, NC, Columbus County, NC, Craven County, NC, Duplin County, NC, Hyde County, NC, Jones County, NC, New Hanover County, NC, Onslow County, NC, Pamlico County, NC, Pender County, NC, Dillon County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Williamsburg County, SC
The radar
The Wilmington radar (KLTX), 22 km from the middle of the area, began a volume at 23:30 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, 11.5 hours before the alert went out and 145 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
- 2134 J/kg
- Mixed-layer CIN
- -49 J/kg
- Mixed-layer LCL
- 866 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 100 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 4.7
The text
As transmitted, in the capitals the NWS used until 2016.
824 ACUS11 KWNS 282329 SWOMCD SPC MCD 282328 NCZ000-SCZ000-290000- MESOSCALE DISCUSSION 1639 NWS STORM PREDICTION CENTER NORMAN OK 0628 PM CDT SAT JUL 28 2012 AREAS AFFECTED...NRN COASTAL SC / SRN-CNTRL COASTAL NC CONCERNING...SEVERE THUNDERSTORM WATCH 536... VALID 282328Z - 290000Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 536 CONTINUES. SUMMARY...THE REMAINING SEVERE WIND GUST RISK WILL BE CONFINED TO THE CAPE LOOKOUT VICINITY AND WILL DIMINISH WITHIN THE NEXT HR OR SO. ELSEWHERE...A DETRIMENTAL COLD POOL HAS EFFECTIVELY OVERTURNED THE AIRMASS ACROSS THE SC-NC COASTAL PLAIN LARGELY NEGATING FURTHER SEVERE POTENTIAL. DISCUSSION...RADAR/SURFACE COMPOSITE SHOWS AN AGGREGATE SEA BREEZE/CONVECTIVE OUTFLOW COLD POOL SPREADING OUTWARD AND FURTHER INLAND AWAY FROM THE COAST. THE AIRMASS IS BEGINNING TO STABILIZE BEHIND THE BOUNDARY ACROSS THE COASTAL PLAIN...PER DROP IN TEMPS INTO THE 70S AND LOWER 80S. THE REMAINING SEVERE WIND RISK WILL BE CONFINED TO THE CAPE LOOKOUT VICINITY OVER THE NEXT HR BEFORE CONVECTIVE OVERTURNING RESULTS IN WEAKENING OF THIS ACTIVITY. SEVERE WATCH 536 WILL LIKELY BE ALLOWED TO BE CLEARED/CANCELLED EARLY FOR THE COASTAL PLAIN. ..SMITH/MEAD.. 07/28/2012 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CHS... LAT...LON 33047891 33477997 34467949 35657626 35057595 33047891
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 28, 1:57 PM EDT | Mesoscale Discussion | SPC | Avery, Buncombe, Burke, Caldwell, Cherokee, Clay and 16 more | 3 hr |
| Jul 28, 2:18 PM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Beaufort, Bertie, Bladen, Brunswick and 61 more | 117 min |
| Jul 28, 4:01 PM EDT | Severe Thunderstorm Watch | SPC | Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 17 more | 6 hr |
Nearby
Mesoscale Discussions in North Carolina, 2012Mesoscale Discussions in South 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.