Alert archive / Nebraska / Mesoscale Discussions in 2015

Mesoscale Discussion 654

May 15, 201515 counties in Nebraska

The Storm Prediction Center issued this mesoscale discussion at May 15, 2015, 9:53 PM MDT for 15 counties in Nebraska. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: May 15, 2015, 9:53 PM MDT (03:53 UTC)
Expired: May 15, 2015, 11:00 PM MDT
In force: 67 min
Issued by: the Storm Prediction Center

Counties Arthur County, NE, Chase County, NE, Cherry County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Perkins County, NE, Sheridan County, NE, Thomas County, NE

The radar

The North Platte radar (KLNX), 102 km from the middle of the area, began a volume at 03:53 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, 3.9 hours before the alert went out and 79 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: 766 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 1526 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 283 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 5.9

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
May 15, 7:55 PM MDT	Severe Thunderstorm Watch	SPC	Arthur, Chase, Cherry, Deuel, Frontier, Garden and 10 more	4 hr
May 15, 11:43 PM MDT	Mesoscale Discussion	SPC	Adams, Buffalo, Franklin, Furnas, Gosper, Hall and 6 more	92 min
May 16, 12:15 PM MDT	Mesoscale Discussion	SPC	Frontier, Furnas, Gosper, Hitchcock, Red Willow	90 min
May 16, 1:41 PM MDT	Tornado Watch	SPC	Furnas, Harlan, Hitchcock, Red Willow	5 hr
May 16, 2:34 PM MDT	Mesoscale Discussion	SPC	Burt, Cass, Cuming, Dakota, Dixon, Dodge and 11 more	86 min
May 16, 4:12 PM MDT	Mesoscale Discussion	SPC	Furnas, Harlan, Hitchcock, Red Willow	93 min
May 16, 5:23 PM MDT	Mesoscale Discussion	SPC	Blaine, Buffalo, Custer, Dawson, Franklin, Frontier and 17 more	97 min

Nearby

Mesoscale Discussions in Nebraska, 2015 Every mesoscale discussion in 2015

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.