Alert archive / Nebraska / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 71, NWS Omaha, NE
NWS Omaha, NE issued this severe thunderstorm warning at Jun 18, 2020, 1:56 PM CDT for Cass County, Nebraska; Mills County, Iowa. It was in force for 20 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
- Jun 18, 2020, 1:56 PM CDT (18:56 UTC)
- Expired
- Jun 18, 2020, 2:16 PM CDT
- In force
- 20 min
- Issued by
- NWS Omaha, NE
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 65.0 mph
Counties Mills County, IA, Cass County, NE
The radar
The Omaha radar (KOAX), 56 km from the middle of the area, began a volume at 18:56 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
Omaha, NE (KOAX), launched 12:00Z, 6.9 hours before the alert went out and 56 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.
- Mixed-layer CAPE
- 154 J/kg
- Mixed-layer CIN
- -296 J/kg
- Mixed-layer LCL
- 1431 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 81 m²/s²
- 0-3 km storm-relative helicity
- 102 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Jun 18, 12:41 PM CDT, 1 hour 15 minutes earlier.
Area forecast discussion, Jun 18, 12:41 PM CDT, 1 hour 15 minutes before
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</html>Hazardous weather outlook, Jun 18, 12:34 PM CDT, 1 hour 22 minutes before
Hazardous Weather Outlook National Weather Service Omaha/Valley NE 1234 PM CDT Thu Jun 18 2020 IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034- 042>045-050>053-065>068-078-088>093-190745- Monona-Harrison-Shelby-Pottawattamie-Mills-Montgomery-Fremont- Page-Knox-Cedar-Thurston-Antelope-Pierce-Wayne-Boone-Madison- Stanton-Cuming-Burt-Platte-Colfax-Dodge-Washington-Butler- Saunders-Douglas-Sarpy-Seward-Lancaster-Cass-Otoe-Saline- Jefferson-Gage-Johnson-Nemaha-Pawnee-Richardson- 1234 PM CDT Thu Jun 18 2020 This Hazardous Weather Outlook is for portions of southwest Iowa...west central Iowa...east central Nebraska...northeast Nebraska and southeast Nebraska. .DAY ONE...This Afternoon and Tonight There is a marginal risk for severe weather today. A cold front will slowly move through the area leading to rain, and possibly some isolated strong storms. Heavy rain and strong winds are the most likely threats. The time frame for severe weather will be from 2 PM to 10 PM. .DAYS TWO THROUGH SEVEN...Friday through Wednesday There are several chances for rain through the weekend which could lead to elevated stream levels and a risk for flooding. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
In the hours before
Special weather statement, Jun 18, 1:22 PM CDT, 34 minutes before
Special Weather Statement National Weather Service Omaha/Valley Nebraska 122 PM CDT Thu Jun 18 2020 NEZ051-066-067-181845- Saunders NE-Cass NE-Lancaster NE- 122 PM CDT Thu Jun 18 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN LANCASTER...SOUTH CENTRAL SAUNDERS AND WEST CENTRAL CASS COUNTIES UNTIL 145 PM CDT... At 121 PM CDT, Doppler radar was tracking a strong thunderstorm over northeastern Lincoln, moving northeast at 25 mph. Hail up to nickel size and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Lincoln, Waverly, Greenwood and Davey. This includes Interstate 80 in Nebraska between mile markers 397 and 423. LAT...LON 4070 9660 4080 9680 4113 9658 4098 9628 TIME...MOT...LOC 1821Z 214DEG 23KT 4082 9665 MILLER
Special weather statement, Jun 18, 1:52 PM CDT, 4 minutes before
Special Weather Statement National Weather Service Omaha/Valley Nebraska 152 PM CDT Thu Jun 18 2020 IAZ079-NEZ053-067-181915- Mills IA-Cass NE-Sarpy NE- 152 PM CDT Thu Jun 18 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MILLS...EAST CENTRAL SARPY AND NORTHEASTERN CASS COUNTIES UNTIL 215 PM CDT... At 152 PM CDT, Doppler radar was tracking a strong thunderstorm over Murray, or 23 miles south of Omaha, moving northeast at 20 mph. Penny size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Plattsmouth, Glenwood, Pacific Junction and Murray. This includes Interstate 29 between mile markers 29 and 37. LAT...LON 4083 9591 4090 9607 4111 9589 4106 9570 TIME...MOT...LOC 1852Z 213DEG 18KT 4092 9597 MILLER
The office that day
Everything else NWS Omaha, NE issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 18, 7:25 AM CDT | Special Weather Statement | OAX | Wayne | 35 min |
| Jun 18, 1:22 PM CDT | Special Weather Statement | OAX | Lancaster | 23 min |
| Jun 18, 1:52 PM CDT | Special Weather Statement | OAX | Cass | 23 min |
| Jun 18, 2:53 PM CDT | Special Weather Statement | OAX | Douglas | 22 min |
| Jun 18, 3:01 PM CDT | Severe Thunderstorm Warning | OAX | Washington | 29 min |
| Jun 18, 3:11 PM CDT | Special Weather Statement | OAX | Lancaster | 34 min |
| Jun 18, 3:20 PM CDT | Severe Thunderstorm Warning | OAX | Lancaster | 40 min |
| Jun 18, 3:53 PM CDT | Severe Thunderstorm Warning | OAX | Cass, Lancaster, Otoe | 52 min |
| Jun 18, 4:18 PM CDT | Special Weather Statement | OAX | Saline | 27 min |
| Jun 18, 4:23 PM CDT | Severe Thunderstorm Warning | OAX | Lancaster, Otoe | 37 min |
| Jun 18, 4:33 PM CDT | Areal Flood Advisory | OAX | Lancaster | 49 min |
| Jun 18, 4:58 PM CDT | Severe Thunderstorm Warning | OAX | Lancaster, Otoe | 47 min |
| Jun 18, 5:10 PM CDT | Severe Thunderstorm Warning | OAX | Gage, Jefferson, Saline | 50 min |
| Jun 18, 5:18 PM CDT | Flash Flood Warning | OAX | Lancaster, Otoe | 4 hr |
| Jun 18, 5:32 PM CDT | Special Weather Statement | OAX | Saline | 28 min |
| Jun 18, 5:53 PM CDT | Severe Thunderstorm Warning | OAX | Gage, Lancaster | 52 min |
| Jun 18, 6:03 PM CDT | Severe Thunderstorm Warning | OAX | Jefferson | 42 min |
| Jun 18, 6:21 PM CDT | Flash Flood Warning | OAX | Gage, Jefferson, Saline | 3 hr |
| Jun 18, 6:30 PM CDT | Severe Thunderstorm Warning | OAX | Gage, Jefferson | 45 min |
| Jun 18, 6:44 PM CDT | Severe Thunderstorm Warning | OAX | Gage | 31 min |
Nearby
Severe Thunderstorm Warnings in Nebraska, 2020Severe Thunderstorm Warnings in Iowa, 2020Every 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.