Alert archive / North Carolina / Mesoscale Discussions in 2020

Mesoscale Discussion 1876

December 24, 202012 counties in North Carolina; Horry County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at Dec 24, 2020, 3:08 PM EST for 12 counties in North Carolina; Horry County, South Carolina. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Dec 24, 2020, 3:08 PM EST (20:08 UTC)
Expired: Dec 24, 2020, 5:15 PM EST
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Tornado watch 518

Counties Bladen County, NC, Columbus County, NC, Duplin County, NC, Edgecombe County, NC, Greene County, NC, Lenoir County, NC, Martin County, NC, Pender County, NC, Pitt County, NC, Sampson County, NC, Wayne County, NC, Wilson County, NC, Horry County, SC

The radar

The Raleigh/Durham radar (KRAX), 74 km from the middle of the area, began a volume at 20:07 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, 8.1 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 35 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 1064 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 188 m²/s²
0-3 km storm-relative helicity: 230 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 24, 12:16 PM EST	Mesoscale Discussion	SPC	Bladen, Brunswick, Columbus, Cumberland, Duplin, Harnett and 8 more	2 hr
Dec 24, 2:19 PM EST	Tornado Watch	SPC	Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 29 more	9 hr
Dec 24, 2:28 PM EST	Mesoscale Discussion	SPC	Avery, Buncombe, Haywood, Madison, Mitchell, Yancey	5 hr
Dec 24, 4:45 PM EST	Mesoscale Discussion	SPC	Bertie, Camden, Chowan, Currituck, Edgecombe, Gates and 7 more	60 min

Nearby

Mesoscale Discussions in North Carolina, 2020 Mesoscale Discussions in South Carolina, 2020 Every mesoscale discussion in 2020

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.