Alert archive / North Carolina / Mesoscale Discussions in 2007

Mesoscale Discussion 471

April 12, 200712 counties in North Carolina

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2007, 8:25 AM EDT for 12 counties in North Carolina. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2007, 8:25 AM EDT (12:25 UTC)
Expired: Apr 12, 2007, 10:00 AM EDT
In force: 95 min
Issued by: the Storm Prediction Center

Counties Beaufort County, NC, Camden County, NC, Carteret County, NC, Craven County, NC, Currituck County, NC, Dare County, NC, Hyde County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC

The radar

The Morehead City radar (KMHX), 71 km from the middle of the area, began a volume at 12:26 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 0.4 hours before the alert went out and 308 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: 68 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 496 m above ground
0-6 km bulk shear: 76 kt
0-1 km storm-relative helicity: 461 m²/s²
0-3 km storm-relative helicity: 416 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 12, 12:16 AM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Bladen, Cabarrus, Chatham, Cumberland and 31 more	89 min
Apr 12, 12:55 AM EDT	Severe Thunderstorm Watch	SPC	Alamance, Anson, Bertie, Bladen, Cabarrus, Caswell and 40 more	3 hr
Apr 12, 2:39 AM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 35 more	66 min
Apr 12, 3:25 AM EDT	Tornado Watch	SPC	Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 36 more	8 hr
Apr 12, 6:18 AM EDT	Mesoscale Discussion	SPC	Beaufort, Bertie, Brunswick, Camden, Carteret, Chowan and 20 more	57 min

Nearby

Mesoscale Discussions in North Carolina, 2007 Every mesoscale discussion in 2007

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.