Alert archive / Nebraska / Mesoscale Discussions in 2023

Mesoscale Discussion 686

May 6, 20237 counties in Iowa; 10 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 6, 2023, 1:42 AM CDT for 7 counties in Iowa; 10 counties in Nebraska. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 6, 2023, 1:42 AM CDT (06:42 UTC)
Expired: May 6, 2023, 3:45 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 5%

Counties Cherokee County, IA, Crawford County, IA, Harrison County, IA, Ida County, IA, Monona County, IA, Sac County, IA, Woodbury County, IA, Burt County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE

The radar

The Omaha radar (KOAX), 75 km from the middle of the area, began a volume at 06:45 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 6.7 hours before the alert went out and 346 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: 701 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 1801 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 161 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.9

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
May 6, 3:20 PM CDT	Mesoscale Discussion	SPC	Adams, Appanoose, Clarke, Davis, Decatur, Fremont and 12 more	2 hr
May 6, 3:56 PM CDT	Tornado Watch	SPC	Adair, Adams, Appanoose, Clarke, Davis, Decatur and 14 more	7 hr
May 5, 7:45 PM CDT	Mesoscale Discussion	SPC	Adams, Arthur, Chase, Dawson, Deuel, Dundy and 16 more	2 hr
May 5, 11:04 PM CDT	Mesoscale Discussion	SPC	Buffalo, Dawson, Gosper, Hall, Hamilton, Howard and 4 more	116 min
May 6, 5:32 PM CDT	Mesoscale Discussion	SPC	Antelope, Blaine, Boone, Boyd, Brown, Buffalo and 35 more	88 min

Nearby

Mesoscale Discussions in Nebraska, 2023 Mesoscale Discussions in Iowa, 2023 Every mesoscale discussion in 2023

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.