Alert archive / Iowa / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 288, NWS Omaha, NE

July 5, 2014Pottawattamie County, Shelby County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at Jul 5, 2014, 4:34 AM CDT for Pottawattamie County, Shelby County, Iowa. It was in force for 21 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: Jul 5, 2014, 4:34 AM CDT (09:34 UTC)
Expired: Jul 5, 2014, 4:55 AM CDT
In force: 21 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Pottawattamie County, IA, Shelby County, IA

The radar

The Omaha radar (KOAX), 81 km from the middle of the area, began a volume at 09:37 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, 9.6 hours before the alert went out and 82 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1704 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 229 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

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 Jul 5, 4:12 AM CDT, 22 minutes earlier.

Area forecast discussion, Jul 5, 4:12 AM CDT, 22 minutes before

<!doctype html>
<html lang="en">
<head>
  <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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Jul 5, 4:26 AM CDT, 8 minutes before

<!doctype html>
<html lang="en">
<head>
  <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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

In the hours before

Local storm report, Jul 5, 2:29 AM CDT, 2 hours 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
229 AM CDT SAT JUL 05 2014

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

0227 AM     HAIL             1 SW PENDER             42.10N 96.72W
07/05/2014  E0.75 INCH       THURSTON           NE   EMERGENCY MNGR

            WINDS GUSTING TO 35 MPH AS WELL.

&&

PEARSON

Special weather statement, Jul 5, 2:36 AM CDT, 1 hour 58 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
236 AM CDT SAT JUL 5 2014

IAZ043-NEZ015-033-050815-
MONONA IA-THURSTON NE-CUMING NE-
236 AM CDT SAT JUL 5 2014

...SPECIAL WEATHER STATEMENT...

AT 235 AM CDT...EMERGENCY MANAGEMENT REPORTED A STRONG THUNDERSTORM
NEAR WALTHILL...OR 25 MILES SOUTHWEST OF SIOUX CITY...MOVING EAST AT
25 MPH.

HALF INCH HAIL WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
WALTHILL...WINNEBAGO...WHITING...MACY AND THURSTON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

LAT...LON 4227 9648 4227 9635 4226 9633 4223 9632
      4222 9633 4221 9608 4209 9608 4205 9668
      4223 9674 4228 9651
TIME...MOT...LOC 0735Z 257DEG 22KT 4216 9660

PEARSON

Special weather statement, Jul 5, 2:44 AM CDT, 1 hour 50 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
244 AM CDT SAT JUL 5 2014

IAZ043-NEZ015-033-034-050830-
MONONA IA-BURT NE-THURSTON NE-CUMING NE-
244 AM CDT SAT JUL 5 2014

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MONONA...NORTHERN
BURT...NORTHEASTERN CUMING AND SOUTHEASTERN THURSTON COUNTIES UNTIL
330 AM CDT...

AT 244 AM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
LYONS...OR 36 MILES SOUTH OF SIOUX CITY...MOVING EAST AT 25 MPH.

HALF INCH HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH
THIS STORM.

LOCATIONS IMPACTED INCLUDE...
ONAWA...LYONS...BANCROFT...DECATUR...BLENCOE...ROSALIE AND LEWIS AND
CLARK STATE PARK.

LAT...LON 4190 9662 4206 9668 4210 9608 4193 9605
TIME...MOT...LOC 0744Z 257DEG 21KT 4198 9650

PEARSON

Special weather statement, Jul 5, 3:05 AM CDT, 1 hour 29 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
305 AM CDT SAT JUL 5 2014

IAZ043-050830-
MONONA IA-
305 AM CDT SAT JUL 5 2014

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN MONONA COUNTY UNTIL
330 AM CDT...

AT 305 AM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
UTE...OR 16 MILES WEST OF DENISON...MOVING NORTHEAST AT 10 MPH.

NICKEL SIZE HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH
THIS STORM.

LOCATIONS IMPACTED INCLUDE...
UTE AND MAPLETON.

LAT...LON 4203 9573 4221 9582 4221 9567 4203 9567
TIME...MOT...LOC 0805Z 245DEG 8KT 4208 9566

PEARSON

Special weather statement, Jul 5, 3:11 AM CDT, 1 hour 23 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
311 AM CDT SAT JUL 5 2014

IAZ043-055-069-NEZ034-045-050900-
HARRISON IA-POTTAWATTAMIE IA-MONONA IA-BURT NE-WASHINGTON NE-
311 AM CDT SAT JUL 5 2014

...SIGNIFICANT WEATHER ADVISORY FOR HARRISON...NORTHWESTERN
POTTAWATTAMIE...SOUTHEASTERN MONONA...SOUTHEASTERN BURT AND CENTRAL
WASHINGTON COUNTIES UNTIL 400 AM CDT...

AT 311 AM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
TEKAMAH...OR 33 MILES NORTH OF OMAHA...MOVING EAST AT 25 MPH.

NICKEL SIZE HAIL AND WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH
THIS STORM.

LOCATIONS IMPACTED INCLUDE...
BLAIR...MISSOURI VALLEY...TEKAMAH...LOGAN...FORT CALHOUN...
MONDAMIN...KENNARD...MODALE...PISGAH...MOORHEAD...CRAIG...WOODBINE...
DUNLAP...HERMAN...BLENCOE...MAGNOLIA...LITTLE SIOUX...PELICAN POINT
STATE RECREATION AREA...SUMMIT LAKE STATE RECREATION AREA AND DESOTO
BEND NATIONAL WILDLIFE REFUGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

LAT...LON 4140 9621 4191 9644 4196 9567 4187 9567
      4186 9560 4152 9557
TIME...MOT...LOC 0811Z 257DEG 24KT 4172 9623

PEARSON

Local storm report, Jul 5, 4:24 AM CDT, 10 minutes before

<!doctype html>
<html lang="en">
<head>
  <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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 5, 1:01 AM CDT	Special Weather Statement	OAX	Knox	59 min
Jul 5, 1:18 AM CDT	Special Weather Statement	OAX	Knox	12 min
Jul 5, 1:24 AM CDT	Severe Thunderstorm Warning	OAX	Knox	51 min
Jul 5, 1:50 AM CDT	Special Weather Statement	OAX	Burt	55 min
Jul 5, 2:36 AM CDT	Special Weather Statement	OAX	Thurston	39 min
Jul 5, 2:44 AM CDT	Special Weather Statement	OAX	Burt	46 min
Jul 5, 2:49 AM CDT	Severe Thunderstorm Warning	OAX	Thurston	56 min
Jul 5, 3:11 AM CDT	Special Weather Statement	OAX	Burt, Washington	49 min
Jul 5, 3:23 AM CDT	Severe Thunderstorm Warning	OAX	Burt, Washington	52 min
Jul 5, 3:27 AM CDT	Areal Flood Advisory	OAX	Cedar	5 hr
Jul 5, 3:59 AM CDT	Areal Flood Advisory	OAX	Burt, Thurston	5 hr
Jul 5, 6:16 AM CDT	Areal Flood Advisory	OAX	Otoe	3 hr
Jul 5, 7:36 AM CDT	Areal Flood Warning	OAX	Cedar	6 hr
Jul 5, 5:14 PM CDT	River Flood Warning	OAX	Nemaha	54 hr
Jul 5, 3:05 AM CDT	Special Weather Statement	OAX	Monona	25 min
Jul 5, 4:15 AM CDT	Severe Thunderstorm Warning	OAX	Harrison, Shelby	45 min
Jul 5, 4:59 AM CDT	Areal Flood Advisory	OAX	Monona	5 hr
Jul 5, 5:35 AM CDT	Special Weather Statement	OAX	Montgomery, Page	40 min
Jul 5, 6:32 AM CDT	Areal Flood Advisory	OAX	Pottawattamie	3 hr
Jul 5, 6:39 AM CDT	Areal Flood Advisory	OAX	Montgomery	3 hr
Jul 5, 7:14 AM CDT	Areal Flood Advisory	OAX	Mills, Montgomery	5 hr
Jul 5, 9:23 AM CDT	River Flood Warning	OAX	Montgomery	22 hr
Jul 5, 9:23 AM CDT	River Flood Warning	OAX	Fremont, Montgomery	40 hr
Jul 5, 12:05 PM CDT	Areal Flood Advisory	OAX	Mills, Montgomery	5 hr
Jul 5, 3:50 PM CDT	Areal Flood Warning	OAX	Fremont, Mills, Montgomery, Pottawattamie	6 hr
Jul 5, 4:58 PM CDT	Areal Flood Warning	OAX	Fremont	9 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2014 Every severe thunderstorm warning in 2014

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.