Alert archive / North Carolina / Mesoscale Discussions in 2017
Mesoscale Discussion 1613
The Storm Prediction Center issued this mesoscale discussion at Sep 1, 2017, 7:23 PM EDT for 31 counties in North Carolina; Cherokee County, York County, South Carolina. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Sep 1, 2017, 7:23 PM EDT (23:23 UTC)
- Expired
- Sep 1, 2017, 9:00 PM EDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
All 33 counties
Alexander County, NC, Anson County, NC, Bladen County, NC, Burke County, NC, Cabarrus County, NC, Caldwell County, NC, Catawba County, NC, Chatham County, NC, Cleveland County, NC, Cumberland County, NC, Davidson County, NC, Davie County, NC, Gaston County, NC, Harnett County, NC, Hoke County, NC, Iredell County, NC, Johnston County, NC, Lee County, NC, Lincoln County, NC, Mecklenburg County, NC, Montgomery County, NC, Moore County, NC, Randolph County, NC, Richmond County, NC, Robeson County, NC, Rowan County, NC, Sampson County, NC, Scotland County, NC, Stanly County, NC, Union County, NC, Wake County, NC, Cherokee County, SC, York County, SC
The radar
The Columbia radar (KCAE), 158 km from the middle of the area, began a volume at 23:26 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
Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 11.4 hours before the alert went out and 104 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
- 208 J/kg
- Mixed-layer CIN
- -38 J/kg
- Mixed-layer LCL
- 585 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 143 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted.
187 ACUS11 KWNS 012323 SWOMCD SPC MCD 012323 NCZ000-SCZ000-020100- Mesoscale Discussion 1613 NWS Storm Prediction Center Norman OK 0623 PM CDT Fri Sep 01 2017 Areas affected...Portions of the Carolinas Concerning...Tornado Watch 477... Valid 012323Z - 020100Z The severe weather threat for Tornado Watch 477 continues. SUMMARY...Tornado threat continues across WW477, primarily over eastern portions of the watch. DISCUSSION...Considerable amount of convective overturning has occurred across northern portions of WW477 which is reinforcing a well-defined boundary that is currently draped from near CLT to GSB. While the storm mode has gradually evolved into clusters and short line segments, a few supercells persist, especially near the wind shift over eastern portions of the watch. As diurnal cooling commences this evening weakening buoyancy should limit eastward extent of severe threat over coastal regions. While isolated severe may be noted immediately downstream of WW477 over the next hour or so at this time a new WW is not anticipated east of the current watch. ..Darrow.. 09/01/2017 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM...RNK...CAE...GSP... LAT...LON 34778176 36048175 35867813 34577815 34778176
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 1, 1:07 PM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Cabarrus, Catawba, Chatham, Cleveland and 13 more | 113 min |
| Sep 1, 1:49 PM EDT | Tornado Watch | SPC | Alexander, Anson, Bladen, Burke, Cabarrus, Caldwell and 27 more | 8 hr |
| Sep 1, 4:44 PM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Cabarrus, Chatham, Cumberland, Davidson and 22 more | 91 min |
| Sep 1, 3:06 PM EDT | Mesoscale Discussion | SPC | Aiken, Allendale, Bamberg, Barnwell, Beaufort, Berkeley and 18 more | 2 hr |
Nearby
Mesoscale Discussions in North Carolina, 2017Mesoscale Discussions in South Carolina, 2017Every mesoscale discussion in 2017
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.