Alert archive / Nebraska / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 154, NWS Omaha, NE

August 9, 20204 counties in Nebraska; Harrison County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at Aug 9, 2020, 7:26 AM CDT for 4 counties in Nebraska; Harrison County, Iowa. It was in force for 34 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: Aug 9, 2020, 7:26 AM CDT (12:26 UTC)
Expired: Aug 9, 2020, 8:00 AM CDT
In force: 34 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon
Hail: 0.75 in
Wind: 75.0 mph

Counties Harrison County, IA, Dodge County, NE, Douglas County, NE, Saunders County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 17 km from the middle of the area, began a volume at 12:28 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

Topeka, KS (KTOP), launched 12:00Z, 0.4 hours before the alert went out and 279 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: 505 J/kg
Mixed-layer CIN: -362 J/kg
Mixed-layer LCL: 1569 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 310 m²/s²
0-3 km storm-relative helicity: 180 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 Aug 9, 6:21 AM CDT, 1 hour 5 minutes earlier.

Area forecast discussion, Aug 9, 6:21 AM CDT, 1 hour 5 minutes before

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Hazardous weather outlook, Aug 9, 4:02 AM CDT, 3 hours 24 minutes before

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In the hours before

Special weather statement, Aug 9, 4:59 AM CDT, 2 hours 27 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
Aug 9, 12:21 AM CDT	Severe Thunderstorm Warning	OAX	Antelope, Knox, Pierce	39 min
Aug 9, 12:42 AM CDT	Special Weather Statement	OAX	Antelope	18 min
Aug 9, 12:56 AM CDT	Special Weather Statement	OAX	Antelope, Knox, Pierce	34 min
Aug 9, 1:20 AM CDT	Special Weather Statement	OAX	Cedar	40 min
Aug 9, 2:55 AM CDT	Heat Advisory	OAX	Cass, Douglas, Gage, Jefferson, Johnson, Lancaster and 8 more	13 hr
Aug 9, 4:59 AM CDT	Special Weather Statement	OAX	Saunders	31 min
Aug 9, 7:59 AM CDT	Special Weather Statement	OAX	Harrison	46 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2020 Severe Thunderstorm Warnings in Iowa, 2020 Every severe thunderstorm warning in 2020

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.