Alert archive / Iowa / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 203, NWS Des Moines, IA

August 1, 20134 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 1, 2013, 6:25 PM CDT for 4 counties in Iowa. It was in force for 50 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 1, 2013, 6:25 PM CDT (23:25 UTC)
Expired
Aug 1, 2013, 7:15 PM CDT
In force
50 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Butler County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA

The radar

The Des Moines radar (KDMX), 109 km from the middle of the area, began a volume at 23:27 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 12:00Z, 11.4 hours before the alert went out and 259 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 12:00Z on 2013-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2013-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 64 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1617 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
64 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 1, 6:25 PM CDT, 0 minutes earlier.

Area forecast discussion, Aug 1, 6:25 PM CDT, 0 minutes before
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Hazardous weather outlook, Aug 1, 4:30 PM CDT, 1 hour 55 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
430 PM CDT THU AUG 1 2013

IAZ004>007-015>017-023>026-033>035-044>046-057-058-070-071-081-082-
092-093-022130-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-SAC-CALHOUN-WEBSTER-CRAWFORD-
CARROLL-GREENE-AUDUBON-GUTHRIE-CASS-ADAIR-ADAMS-UNION-TAYLOR-
RINGGOLD-
430 PM CDT THU AUG 1 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS OVER WESTERN AND NORTHERN IOWA WILL
BECOME MORE WIDESPREAD AND MOVE EAST OVERNIGHT. A FEW STORMS COULD
BE STRONG TO SEVERE UNTIL LATE EVENING...WITH LARGE HAIL AND
DAMAGING WINDS POSSIBLE. OVERNIGHT THE SEVERE WEATHER THREAT WILL
END BUT STORMS WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY
RAINFALL.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS WILL LINGER ON FRIDAY MORNING...MAINLY SOUTH OF
HIGHWAY 20...THEN GRADUALLY MOVE OUT LATER IN THE DAY. SEVERE
WEATHER IS NOT EXPECTED.

THUNDERSTORMS WILL THEN RETURN TO THE FORECAST AT INTERVALS FROM
SUNDAY THROUGH WEDNESDAY. WIDESPREAD SEVERE WEATHER IS NOT
EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

IAZ027-028-036>039-047>050-059>062-072>075-083>086-094>097-022130-
BUTLER-BREMER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-BOONE-STORY-MARSHALL-
TAMA-DALLAS-POLK-JASPER-POWESHIEK-MADISON-WARREN-MARION-MAHASKA-
CLARKE-LUCAS-MONROE-WAPELLO-DECATUR-WAYNE-APPANOOSE-DAVIS-
430 PM CDT THU AUG 1 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

THUNDERSTORMS OVER NORTHERN AND WESTERN IOWA WILL MOVE SOUTHEAST
OVERNIGHT. SEVERE WEATHER IS NOT ANTICIPATED...BUT SOME STORMS WILL
BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL ESPECIALLY
SOUTHWEST OF FORT DODGE TO WATERLOO LINE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS WILL LINGER ON FRIDAY MORNING...MAINLY SOUTH OF
HIGHWAY 20...THEN GRADUALLY MOVE OUT LATER IN THE DAY. SEVERE
WEATHER IS NOT EXPECTED.

THUNDERSTORMS WILL THEN RETURN TO THE FORECAST AT INTERVALS FROM
SUNDAY THROUGH WEDNESDAY. WIDESPREAD SEVERE WEATHER IS NOT
EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

REV

In the hours before

Local storm report, Aug 1, 4:23 PM CDT, 2 hours 2 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
423 PM CDT THU AUG 01 2013

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

0410 PM     HAIL             3 NW GRUVER             43.42N 94.75W
08/01/2013  E1.00 INCH       EMMET              IA   EMERGENCY MNGR

            EMMET COUNTY EMERGENCY MANAGER REPORTED QUARTER SIZE HAIL

&&
Special weather statement, Aug 1, 4:23 PM CDT, 2 hours 2 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
423 PM CDT THU AUG 1 2013

IAZ004>007-015>017-023>026-012330-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-
INCLUDING THE CITIES OF...ESTHERVILLE...ALGONA...FOREST CITY...
NORTHWOOD...EMMETSBURG...GARNER...MASON CITY...POCAHONTAS...
HUMBOLDT...CLARION...HAMPTON
423 PM CDT THU AUG 1 2013

...STRONG THUNDERSTORMS WILL MOVE ACROSS NORTHERN IOWA THIS
AFTERNOON INTO EARLY EVENING...

ISOLATED TO WIDELY SCATTERED THUNDERSTORMS WILL MOVE ACROSS
NORTHERN IOWA INTO THE EARLY EVENING HOURS. THE STORMS ARE MOVING
SOUTHEAST BETWEEN 20 AND 30 MPH AND MAY PRODUCE HAIL TO THE SIZE
OF NICKELS...STRONG WIND GUSTS AND LOCALLY HEAVY RAINFALL. SEEK
SHELTER INDOORS WHEN STORMS APPROACH YOUR AREA.

FAB
Local storm report, Aug 1, 4:57 PM CDT, 1 hour 28 minutes before
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Local storm report, Aug 1, 5:33 PM CDT, 52 minutes before
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Special weather statement, Aug 1, 5:42 PM CDT, 43 minutes before
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Special weather statement, Aug 1, 6:15 PM CDT, 10 minutes before
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The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 1, 4:07 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock, Winnebago, Worth38 min
Aug 1, 4:27 PM CDTSevere Thunderstorm WarningDMXEmmet, Kossuth48 min
Aug 1, 4:45 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock45 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2013Every severe thunderstorm warning in 2013

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.