Alert archive / Nebraska / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 228, NWS Omaha, NE

September 17, 2015Nemaha County, Nebraska

NWS Omaha, NE issued this severe thunderstorm warning at Sep 17, 2015, 6:22 PM CDT for Nemaha County, Nebraska. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 17, 2015, 6:22 PM CDT (23:22 UTC)
Expired: Sep 17, 2015, 6:45 PM CDT
In force: 23 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Nemaha County, NE

The radar

The Omaha radar (KOAX), 112 km from the middle of the area, began a volume at 23:24 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

Topeka, KS (KFOE), launched 12:00Z, 11.4 hours before the alert went out and 155 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: 613 J/kg
Mixed-layer CIN: -397 J/kg
Mixed-layer LCL: 995 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 396 m²/s²
0-3 km storm-relative helicity: 364 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Omaha, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 17, 3:10 PM CDT, 3 hours 12 minutes earlier.

Area forecast discussion, Sep 17, 3:10 PM CDT, 3 hours 12 minutes before

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Hazardous weather outlook, Sep 17, 4:25 PM CDT, 1 hour 57 minutes before

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In the hours before

Special weather statement, Sep 17, 6:14 PM CDT, 8 minutes before

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The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 17, 6:14 PM CDT	Special Weather Statement	OAX	Nemaha, Pawnee	46 min
Sep 17, 6:31 PM CDT	Severe Thunderstorm Warning	OAX	Nemaha, Richardson	44 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2015 Every severe thunderstorm warning 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.