Alert archive / Iowa / Special Weather Statements in 2021

Special Weather Statement, NWS Omaha, NE

April 5, 20214 counties in Iowa

NWS Omaha, NE issued this special weather statement at Apr 5, 2021, 6:28 AM CDT for 4 counties in Iowa. It was in force for 47 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: Apr 5, 2021, 6:28 AM CDT (11:28 UTC)
Expired: Apr 5, 2021, 7:15 AM CDT
In force: 47 min
Issued by: NWS Omaha, NE

Counties Harrison County, IA, Monona County, IA, Pottawattamie County, IA, Shelby County, IA

The radar

The Omaha radar (KOAX), 76 km from the middle of the area, began a volume at 11:28 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

Omaha, NE (KOAX), launched 00:00Z, 11.5 hours before the alert went out and 76 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: 452 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 3078 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 77 m²/s²
0-3 km storm-relative helicity: 150 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

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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 Apr 5, 6:16 AM CDT, 12 minutes earlier.

Area forecast discussion, Apr 5, 6:16 AM CDT, 12 minutes before

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Hazardous weather outlook, Apr 5, 3:47 AM CDT, 2 hours 41 minutes before

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In the hours before

Local storm report, Apr 5, 1:29 AM CDT, 4 hours 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
129 AM CDT MON APR 5 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0111 AM     NON-TSTM WND GST 4 WSW KENNARD           41.44N 96.27W
04/05/2021  M70 MPH          WASHINGTON         NE   MESONET

            MESONET STATION UP342 4.1 SW KENNARD (UPR).

&&

Special weather statement, Apr 5, 2:05 AM CDT, 4 hours 23 minutes before

Special Weather Statement
National Weather Service Omaha/Valley Nebraska
205 AM CDT Mon Apr 5 2021

NEZ043-044-050>053-050800-
Saunders NE-Sarpy NE-Butler NE-Colfax NE-Douglas NE-Dodge NE-
205 AM CDT Mon Apr 5 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN SARPY...COLFAX...
DODGE...WESTERN DOUGLAS...EASTERN BUTLER AND SAUNDERS COUNTIES UNTIL
300 AM CDT...

At 202 AM CDT, Doppler radar was tracking spotty showers across
parts of Platte, Colfax, Dodge, Butler and Saunders counties. These
were moving east at up to 35 mph.

Wind gusts up to around 50 mph will be possible with the outflow
from these showers.

Locations impacted include...
Fremont, Schuyler, Wahoo, Valley, North Bend, Yutan, Scribner,
Hooper, Clarkson, Dodge, Cedar Bluffs, Valparaiso, Mead, Howells,
Nickerson, Brainard, Inglewood, Weston, Prague and Snyder.

LAT...LON 4174 9653 4105 9625 4105 9706 4174 9723
TIME...MOT...LOC 0702Z 267DEG 32KT 4167 9687 4109 9658

Miller

Special weather statement, Apr 5, 2:08 AM CDT, 4 hours 20 minutes before

Special Weather Statement
National Weather Service Omaha/Valley Nebraska
208 AM CDT Mon Apr 5 2021

IAZ043-055-056-069-NEZ034-045-050800-
Pottawattamie IA-Monona IA-Shelby IA-Harrison IA-Burt NE-
Washington NE-
208 AM CDT Mon Apr 5 2021

...SIGNIFICANT WEATHER ADVISORY FOR MONONA...NORTHERN
POTTAWATTAMIE...HARRISON...WESTERN SHELBY...BURT AND NORTHEASTERN
WASHINGTON COUNTIES UNTIL 300 AM CDT...

At 206 AM CDT, Doppler radar was tracking an area of spotty showers
across parts of Burt and Washington counties in Nebraska as well as
parts of Monona, Harrison, Shelby and Pottawattamie counties in
Iowa. These were moving east or northeast at up to 35 mph.

Wind gusts up to around 50 mph will be possible with the
outflow from some of these showers.

Locations impacted include...
Harlan, Onawa, Missouri Valley, Tekamah, Logan, Avoca, Underwood,
Lyons, Walnut, Shelby, Minden, Decatur, Earling, Mondamin, Ute,
Persia, Modale, Pisgah, Moorhead and Woodbine.

LAT...LON 4129 9581 4194 9651 4222 9571 4221 9567
      4187 9567 4186 9541 4144 9515 4143 9516
TIME...MOT...LOC 0706Z 235DEG 17KT 4181 9634 4137 9581

Miller

Special weather statement, Apr 5, 2:52 AM CDT, 3 hours 36 minutes before

Special Weather Statement
National Weather Service Omaha/Valley Nebraska
252 AM CDT Mon Apr 5 2021

NEZ034-044-045-051>053-050845-
Saunders NE-Sarpy NE-Burt NE-Washington NE-Douglas NE-Dodge NE-
252 AM CDT Mon Apr 5 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN SARPY...SOUTHWESTERN
BURT...WASHINGTON...DODGE...DOUGLAS AND EASTERN SAUNDERS COUNTIES
UNTIL 345 AM CDT...

At 250 AM CDT, Doppler radar was tracking scattered light showers in
an area extending from 5 miles south of Scribner to 4 miles north of
Ashland. Movement was east at 35 mph.

Wind gusts up to 50 mph will be possible with some of these
showers.

Locations impacted include...
Omaha, Bellevue, Fremont, Papillion, La Vista, Blair, Ralston,
Gretna, Valley, Tekamah, Arlington, Yutan, Scribner, Waterloo,
Hooper, Cedar Bluffs, Mead, Nickerson, Kennard and Inglewood.

LAT...LON 4115 9589 4106 9646 4169 9686 4181 9624
      4121 9592 4120 9593
TIME...MOT...LOC 0750Z 274DEG 31KT 4160 9666 4110 9637

Miller

Special weather statement, Apr 5, 3:39 AM CDT, 2 hours 49 minutes before

Special Weather Statement
National Weather Service Omaha/Valley Nebraska
339 AM CDT Mon Apr 5 2021

IAZ055-056-069-NEZ034-045-052-050930-
Pottawattamie IA-Shelby IA-Harrison IA-Burt NE-Washington NE-
Douglas NE-
339 AM CDT Mon Apr 5 2021

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL POTTAWATTAMIE...
HARRISON...SOUTHWESTERN SHELBY...SOUTHEASTERN BURT...CENTRAL
WASHINGTON AND NORTHEASTERN DOUGLAS COUNTIES UNTIL 430 AM CDT...

At 338 AM CDT, Doppler radar was tracking an area of spotty showers
that were producing gusty winds. Movement was east at 35 mph.

Wind gusts up to 50 mph will be possible with some of these
showers.

Locations impacted include...
Northeastern Omaha, northeastern Council Bluffs, Blair, Missouri
Valley, Logan, Oakland, Underwood, Fort Calhoun, Shelby, Minden,
Mondamin, Persia, Modale, Carter Lake, Woodbine, Neola, Crescent,
Herman, Hancock and Portsmouth.

This includes the following highways...
 Interstate 29 between mile markers 56 and 89.
 Interstate 80 in Iowa between mile markers 5 and 37.

LAT...LON 4183 9562 4130 9522 4122 9582 4167 9632
TIME...MOT...LOC 0838Z 261DEG 31KT 4164 9620 4125 9579

Miller

Special weather statement, Apr 5, 6:28 AM CDT, 0 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
Apr 4, 8:21 PM CDT	Special Weather Statement	OAX	Butler	39 min
Apr 4, 10:44 PM CDT	Special Weather Statement	OAX	Platte	31 min
Apr 4, 11:03 PM CDT	Severe Thunderstorm Warning	OAX	Butler, Colfax, Platte	14 min
Apr 4, 11:47 PM CDT	Special Weather Statement	OAX	Colfax	28 min
Apr 5, 12:24 AM CDT	Severe Thunderstorm Warning	OAX	Dodge, Douglas, Sarpy, Saunders, Washington	36 min
Apr 5, 1:07 AM CDT	Severe Thunderstorm Warning	OAX	Burt, Dodge, Washington	23 min
Apr 5, 1:28 AM CDT	Severe Thunderstorm Warning	OAX	Douglas, Washington	32 min
Apr 5, 2:05 AM CDT	Special Weather Statement	OAX	Colfax, Dodge, Saunders	55 min
Apr 5, 2:08 AM CDT	Special Weather Statement	OAX	Burt	52 min
Apr 5, 2:52 AM CDT	Special Weather Statement	OAX	Dodge, Douglas, Washington	53 min
Apr 5, 3:39 AM CDT	Special Weather Statement	OAX	Harrison, Pottawattamie	51 min

Nearby

Special Weather Statements in Iowa, 2021 Every 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.