Alert archive / Nebraska / Mesoscale Discussions in 2009

Mesoscale Discussion 396

April 5, 200931 counties in Nebraska; 4 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Apr 5, 2009, 6:28 AM CDT for 31 counties in Nebraska; 4 counties in South Dakota. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Apr 5, 2009, 6:28 AM CDT (11:28 UTC)
Expired: Apr 5, 2009, 10:30 AM CDT
In force: 4 hr
Issued by: the Storm Prediction Center

All 35 counties

Antelope County, NE, Arthur County, NE, Blaine County, NE, Boone County, NE, Boyd County, NE, Brown County, NE, Cedar County, NE, Cuming County, NE, Custer County, NE, Dakota County, NE, Dixon County, NE, Garfield County, NE, Grant County, NE, Greeley County, NE, Holt County, NE, Hooker County, NE, Keith County, NE, Knox County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, Madison County, NE, McPherson County, NE, Pierce County, NE, Rock County, NE, Stanton County, NE, Thomas County, NE, Thurston County, NE, Valley County, NE, Wayne County, NE, Wheeler County, NE, Bon Homme County, SD, Clay County, SD, Union County, SD, Yankton County, SD

The radar

The North Platte radar (KLNX), 137 km from the middle of the area, began a volume at 11:28 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, 11.5 hours before the alert went out and 170 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 629 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 231 m²/s²
0-3 km storm-relative helicity: 778 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 4, 9:11 PM CDT	Mesoscale Discussion	SPC	Antelope, Blaine, Boone, Boyd, Brown, Cedar and 16 more	4 hr

Nearby

Mesoscale Discussions in Nebraska, 2009 Mesoscale Discussions in South Dakota, 2009 Every mesoscale discussion in 2009

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.