Alert archive / Nebraska / Mesoscale Discussions in 2003

Mesoscale Discussion 1871

July 17, 20035 counties in Nebraska; Bennett County, Todd County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 17, 2003, 7:19 PM CDT for 5 counties in Nebraska; Bennett County, Todd County, South Dakota. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued: Jul 17, 2003, 7:19 PM CDT (00:19 UTC)
Expired: Jul 17, 2003, 9:15 PM CDT
In force: 116 min
Issued by: the Storm Prediction Center

Counties Brown County, NE, Cherry County, NE, Keya Paha County, NE, Rock County, NE, Sheridan County, NE, Bennett County, SD, Todd County, SD

The radar

The North Platte radar (KLNX), 100 km from the middle of the area, began a volume at 00:22 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, 0.3 hours before the alert went out and 183 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: 224 J/kg
Mixed-layer CIN: -28 J/kg
Mixed-layer LCL: 4021 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 113 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

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
Jul 18, 4:30 PM CDT	Mesoscale Discussion	SPC	Banner, Box Butte, Dawes, Kimball, Morrill, Scotts Bluff and 2 more	90 min
Jul 18, 4:45 PM CDT	Severe Thunderstorm Watch	SPC	Banner, Box Butte, Cheyenne, Dawes, Deuel, Garden and 5 more	5 hr
Jul 17, 7:41 PM CDT	Mesoscale Discussion	SPC	Harding, Perkins, Ziebach	94 min
Jul 17, 9:05 PM CDT	Severe Thunderstorm Watch	SPC	Butte, Harding, Lawrence, Meade, Pennington, Perkins	5 hr
Jul 17, 11:15 PM CDT	Mesoscale Discussion	SPC	Butte, Harding, Lawrence, Meade, Pennington, Perkins	90 min

Nearby

Mesoscale Discussions in Nebraska, 2003 Mesoscale Discussions in South Dakota, 2003 Every mesoscale discussion in 2003

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.