Alert archive / North Carolina / Mesoscale Discussions in 2021
Mesoscale Discussion 288
The Storm Prediction Center issued this mesoscale discussion at Mar 27, 2021, 7:53 PM EDT for 13 counties in North Carolina. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Mar 27, 2021, 7:53 PM EDT (23:53 UTC)
- Expired
- Mar 27, 2021, 9:30 PM EDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 61
Counties Beaufort County, NC, Carteret County, NC, Craven County, NC, Duplin County, NC, Greene County, NC, Hyde County, NC, Jones County, NC, Lenoir County, NC, Onslow County, NC, Pamlico County, NC, Pitt County, NC, Sampson County, NC, Wayne County, NC
The radar
The Morehead City radar (KMHX), 62 km from the middle of the area, began a volume at 23:50 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, 11.9 hours before the alert went out and 62 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
- 132 J/kg
- Mixed-layer CIN
- -315 J/kg
- Mixed-layer LCL
- 1099 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 7 m²/s²
- 0-3 km storm-relative helicity
- 46 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
823 ACUS11 KWNS 272353 SWOMCD SPC MCD 272353 NCZ000-280130- Mesoscale Discussion 0288 NWS Storm Prediction Center Norman OK 0653 PM CDT Sat Mar 27 2021 Areas affected...Eastern portions of North Carolina Concerning...Severe Thunderstorm Watch 61... Valid 272353Z - 280130Z The severe weather threat for Severe Thunderstorm Watch 61 continues. SUMMARY...Severe storms moving across WW 61 will continue to pose a threat for large hail and damaging wind gusts. DISCUSSION...Regional radar trends show discrete cells that formed ahead of the approaching line of convection in the watch area have now merged, with perhaps a slight uptick in intensity, included embedded supercell structures, as the line encountered improving thermodynamic conditions. The environment ahead of the line remains conducive to sustain severe convection, characterized by MLCAPE/MUCAPE near 1000-1500 J/kg and effective bulk shear near 50 kt. Thus, large hail and damaging wind gusts appear to be the primary hazards before storms move offshore. Given effective SRH values near 150-200 m^2/s^2 across the region, an isolated tornado threat cannot be ruled out. ..Karstens.. 03/27/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM... LAT...LON 34887896 35637782 35777639 35167559 34367682 34887896
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 27, 1:39 PM EDT | Mesoscale Discussion | SPC | Alamance, Alexander, Anson, Burke, Cabarrus, Caldwell and 42 more | 66 min |
| Mar 27, 2:03 PM EDT | Severe Thunderstorm Watch | SPC | Alamance, Alexander, Alleghany, Burke, Cabarrus, Caldwell and 35 more | 6 hr |
| Mar 27, 4:49 PM EDT | Mesoscale Discussion | SPC | Alamance, Caswell, Chatham, Durham, Edgecombe, Franklin and 19 more | 56 min |
| Mar 27, 5:29 PM EDT | Severe Thunderstorm Watch | SPC | Anson, Beaufort, Craven, Cumberland, Duplin, Greene and 13 more | 5 hr |
Nearby
Mesoscale Discussions in North Carolina, 2021Every mesoscale discussion in 2021
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.