Alert archive / Iowa / Special Weather Statements in 2021
Special Weather Statement, NWS Omaha, NE
NWS Omaha, NE issued this special weather statement at May 25, 2021, 5:46 PM CDT for Pottawattamie County, Iowa. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- May 25, 2021, 5:46 PM CDT (22:46 UTC)
- Expired
- May 25, 2021, 6:15 PM CDT
- In force
- 29 min
- Issued by
- NWS Omaha, NE
County Pottawattamie County, IA
The radar
The Omaha radar (KOAX), 58 km from the middle of the area, began a volume at 22:46 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, 10.8 hours before the alert went out and 58 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
- 460 J/kg
- Mixed-layer CIN
- -155 J/kg
- Mixed-layer LCL
- 723 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 144 m²/s²
- 0-3 km storm-relative helicity
- 159 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 3.5
The text
As transmitted.
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</html>What forecasters said that day
The local office's own words before this special weather statement 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 special weather statement went out at May 25, 3:04 PM CDT, 2 hours 42 minutes earlier.
Area forecast discussion, May 25, 3:04 PM CDT, 2 hours 42 minutes before
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<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
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</html>Hazardous weather outlook, May 25, 3:31 PM CDT, 2 hours 15 minutes before
Hazardous Weather Outlook National Weather Service Omaha/Valley NE 331 PM CDT Tue May 25 2021 IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034- 042>045-050>053-065>068-078-088>093-261045- 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- 331 PM CDT Tue May 25 2021 This Hazardous Weather Outlook is for portions of southwest Iowa...west central Iowa...east central Nebraska...northeast Nebraska and southeast Nebraska. .DAY ONE...Tonight and Wednesday A few strong to severe storms appear possible between 4 PM and 10 PM, along and south of a line from Seward to Omaha to Harlan, Iowa. Wind gusts up to 50 to 60 mph and hail to quarter size will be the main hazards. .DAYS TWO THROUGH SEVEN...Wednesday night through Tuesday Additional strong to severe thunderstorms will affect the area on Wednesday night into Thursday morning. While damaging winds and localized flooding will be the main hazards, a few tornadoes cannot be ruled out. Non-severe thunderstorms will be possible from Saturday through Memorial Day. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed through tonight.
In the hours before
Special weather statement, May 25, 5:09 PM CDT, 37 minutes before
Special Weather Statement National Weather Service Omaha/Valley Nebraska 509 PM CDT Tue May 25 2021 NEZ090-091-252245- Johnson NE-Nemaha NE- 509 PM CDT Tue May 25 2021 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN JOHNSON AND NEMAHA COUNTIES UNTIL 545 PM CDT... At 508 PM CDT, Doppler radar was tracking a strong thunderstorm near Johnson, or 30 miles northwest of Falls City, moving east at 20 mph. Hail up to nickel size and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Auburn, Peru, Johnson, Nemaha, Brock, 7 Miles South Of Auburn and 8 Miles South Of Johnson. PRECAUTIONARY/PREPAREDNESS ACTIONS... This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 4026 9610 4048 9608 4048 9572 4026 9566 TIME...MOT...LOC 2208Z 256DEG 18KT 4035 9603 Miller
Special weather statement, May 25, 5:43 PM CDT, 3 minutes before
Special Weather Statement
National Weather Service Omaha/Valley Nebraska
543 PM CDT Tue May 25 2021
NEZ091-252315-
Nemaha NE-
543 PM CDT Tue May 25 2021
...SIGNIFICANT WEATHER ADVISORY FOR NEMAHA COUNTY UNTIL 615 PM CDT...
At 542 PM CDT, Doppler radar was tracking a strong thunderstorm near
Auburn, or 26 miles northwest of Falls City, moving east at 20 mph.
Nickel size hail, winds in excess of 40 mph and rainfall rates of up
to 2 inches per hour will be possible with this storm. Flooding
could develop.
Locations impacted include...
Auburn, Peru, Johnson, Nemaha, Brownville, Brock, Brownville State
Recreation Area, 7 Miles South Of Auburn and 8 Miles South Of
Johnson.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
&&
LAT...LON 4048 9602 4048 9569 4033 9562 4031 9566
4031 9564 4032 9562 4026 9559 4026 9600
TIME...MOT...LOC 2242Z 267DEG 16KT 4036 9591
MillerSpecial weather statement, May 25, 5:46 PM CDT, 0 minutes before
Special Weather Statement National Weather Service Omaha/Valley Nebraska 546 PM CDT Tue May 25 2021 IAZ069-252315- Pottawattamie IA- 546 PM CDT Tue May 25 2021 ...SIGNIFICANT WEATHER ADVISORY FOR WESTERN POTTAWATTAMIE COUNTY UNTIL 615 PM CDT... At 545 PM CDT, Doppler radar was tracking a strong thunderstorm over parts of Council Bluffs, or 10 miles east of Omaha, moving east at 15 mph. Hail up to around nickel size, winds around 45 mph and very heavy rain will be possible with this storm. Locations impacted include... Council Bluffs, Treynor, Underwood, Carson, Macedonia, Crescent, McClelland and Old Town Park. PRECAUTIONARY/PREPAREDNESS ACTIONS... This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 4116 9583 4136 9589 4142 9545 4116 9541 TIME...MOT...LOC 2245Z 255DEG 14KT 4127 9580 Miller
The office that day
Everything else NWS Omaha, NE issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 25, 5:09 PM CDT | Special Weather Statement | OAX | Nemaha | 36 min |
| May 25, 5:43 PM CDT | Special Weather Statement | OAX | Nemaha | 32 min |
| May 25, 5:59 PM CDT | Areal Flood Advisory | OAX | Nemaha | 3 hr |
| May 25, 6:12 PM CDT | Severe Thunderstorm Warning | OAX | Nemaha, Richardson | 48 min |
| May 25, 6:55 PM CDT | Severe Thunderstorm Warning | OAX | Richardson | 50 min |
Nearby
Special Weather Statements in Iowa, 2021Every special weather statement in 2021
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.