Alert archive / Iowa / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 164, NWS Omaha, NE

August 2, 2015Shelby County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at Aug 2, 2015, 4:26 AM CDT for Shelby 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 2, 2015, 4:26 AM CDT (09:26 UTC)
Expired
Aug 2, 2015, 5:00 AM CDT
In force
34 min
Issued by
NWS Omaha, NE
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Shelby County, IA

The radar

The Omaha radar (KOAX), 97 km from the middle of the area, began a volume at 09:29 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

Minneapolis, MN (KMPX), launched 00:00Z, 9.4 hours before the alert went out and 378 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-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2015-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1730 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2015-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 218 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
1730 J/kg
Mixed-layer CIN
-124 J/kg
Mixed-layer LCL
1483 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
218 m²/s²
0-3 km storm-relative helicity
333 m²/s²
Significant tornado parameter
0.4
Supercell composite
14.0

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 Aug 2, 3:58 AM CDT, 28 minutes earlier.

Area forecast discussion, Aug 2, 3:58 AM CDT, 28 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, Aug 1, 4:30 PM CDT, 11 hours 56 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
430 PM CDT SAT AUG 1 2015

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-021130-
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-
430 PM CDT SAT AUG 1 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MOST OF EASTERN NEBRASKA AND
PARTS OF SOUTHWEST IOWA.

.DAY ONE...TONIGHT AND SUNDAY

THERE IS A CHANCE OF THUNDERSTORMS THROUGH THE OVERNIGHT...BUT
ORGANIZED SEVERE WEATHER IS NOT EXPECTED. THERE IS ALSO A SMALL
CHANCE OF STORMS SUNDAY...MOSTLY IN THE AFTERNOON AND MAINLY
ACROSS SOUTHEAST NEBRASKA INTO SOUTHWEST IOWA. A FEW STRONG STORMS
ARE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SUNDAY NIGHT THROUGH SATURDAY

THERE IS A CHANCE OF THUNDERSTORMS MOST OF NEXT WEEK FROM MONDAY
ONWARD...AS SEVERAL WEATHER IMPULSES MOVE ACROSS THE REGION. LATER
OUTLOOKS WILL ADDRESS THE SEVERE WEATHER POTENTIAL IN THOSE
PERIODS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED TO BE NEEDED TONIGHT OR SUNDAY.

In the hours before

Special weather statement, Aug 2, 2:39 AM CDT, 1 hour 47 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
239 AM CDT SUN AUG 2 2015

NEZ033-034-043>045-020830-
DODGE NE-COLFAX NE-WASHINGTON NE-BURT NE-CUMING NE-
239 AM CDT SUN AUG 2 2015

...SIGNIFICANT WEATHER ADVISORY FOR DODGE...NORTHWESTERN
WASHINGTON...SOUTHWESTERN CUMING...NORTHEASTERN COLFAX AND SOUTH
CENTRAL BURT COUNTIES UNTIL 330 AM CDT...

AT 238 AM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
DODGE...OR 28 MILES NORTHEAST OF COLUMBUS...MOVING EAST AT 45 MPH.

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

LOCATIONS IMPACTED INCLUDE...
SCRIBNER...HOOPER...DODGE...HOWELLS...NICKERSON...SNYDER...WINSLOW...
7 MILES NORTH OF NORTH BEND AND DEAD TIMBER STATE RECREATION AREA.

THIS INCLUDES THE FOLLOWING HIGHWAYS...
 HIGHWAY 275 IN NEBRASKA BETWEEN MILE MARKERS 124 AND 140.
 HIGHWAY 77 IN NEBRASKA BETWEEN MILEMARKERS 120 AND 132.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 4177 9699 4171 9632 4161 9629 4147 9638
      4159 9702
TIME...MOT...LOC 0738Z 278DEG 37KT 4167 9690

KG
Special weather statement, Aug 2, 3:39 AM CDT, 47 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.

IssuedProductOfficeCountiesLasted
Aug 2, 2:39 AM CDTSpecial Weather StatementOAXDodge51 min
Aug 2, 2:50 AM CDTSevere Thunderstorm WarningOAXBurt, Dodge, Washington25 min
Aug 2, 6:31 PM CDTSevere Thunderstorm WarningOAXButler59 min
Aug 2, 3:39 AM CDTSpecial Weather StatementOAXHarrison51 min
Aug 2, 4:04 AM CDTSevere Thunderstorm WarningOAXHarrison, Shelby26 min
Aug 2, 4:30 AM CDTSevere Thunderstorm WarningOAXHarrison, Pottawattamie, Shelby45 min
Aug 2, 8:09 AM CDTSpecial Weather StatementOAXFremont51 min
Aug 2, 6:11 PM CDTSevere Thunderstorm WarningOAXMontgomery49 min
Aug 2, 6:25 PM CDTSpecial Weather StatementOAXMills50 min
Aug 2, 6:29 PM CDTSevere Thunderstorm WarningOAXMills61 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2015Every severe thunderstorm warning in 2015

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.