Alert archive / Iowa / Severe Thunderstorm Warnings in 2010

Severe Thunderstorm Warning 347, NWS Des Moines, IA

September 18, 2010Jasper County, Polk County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Sep 18, 2010, 11:18 PM CDT for Jasper County, Polk County, Iowa. It was in force for 42 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: Sep 18, 2010, 11:18 PM CDT (04:18 UTC)
Expired: Sep 19, 2010, 12:00 AM CDT
In force: 42 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Jasper County, IA, Polk County, IA

The radar

The Des Moines radar (KDMX), 34 km from the middle of the area, began a volume at 04:22 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 18, 9:25 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 4.3 hours before the alert went out and 234 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: 675 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 90 m²/s²
0-3 km storm-relative helicity: 345 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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 18, 6:36 PM CDT, 4 hours 42 minutes earlier.

Area forecast discussion, Sep 18, 6:36 PM CDT, 4 hours 42 minutes before

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Hazardous weather outlook, Sep 18, 5:52 PM CDT, 5 hours 26 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
552 PM CDT SAT SEP 18 2010

IAZ046>050-057>062-070>075-081>086-092>097-192300-
GREENE-BOONE-STORY-MARSHALL-TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-
POWESHIEK-CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-
CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-
DAVIS-
552 PM CDT SAT SEP 18 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND
SOUTH CENTRAL IOWA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED TONIGHT. AN ISOLATED SEVERE
STORM CAPABLE OF PRODUCING QUARTER SIZED HAIL IS POSSIBLE.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ISOLATED THUNDERSTORM CHANCES CONTINUE ON SUNDAY THEN SCATTERED
THUNDERSTORMS ARE POSSIBLE SUNDAY NIGHT. ADDITIONAL THUNDERSTORM
ARE POSSIBLE INTERMITTENTLY THROUGHOUT THE WEEK. A FEW SEVERE
STORMS AND LOCALLY HEAVY RAIN MAY OCCUR DURING THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT.

IAZ004>007-015-192300-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-
552 PM CDT SAT SEP 18 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
IOWA.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

CHANCES FOR THUNDERSTORMS RETURN SUNDAY NIGHT THEN INTERMITTENTLY
THROUGHOUT THE WEEK. A FEW SEVERE STORMS AND LOCALLY HEAVY RAIN MAY
OCCUR DURING THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

IAZ016-017-023>028-033>039-044-045-192300-
HANCOCK-CERRO GORDO-POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-
BREMER-SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-
CRAWFORD-CARROLL-
552 PM CDT SAT SEP 18 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

ISOLATED NON SEVERE THUNDERSTORMS ARE POSSIBLE TONIGHT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ISOLATED THUNDERSTORM CHANCES CONTINUE ON SUNDAY THEN SCATTERED
THUNDERSTORMS ARE POSSIBLE SUNDAY NIGHT. ADDITIONAL THUNDERSTORM
ARE POSSIBLE INTERMITTENTLY THROUGHOUT THE WEEK. A FEW SEVERE
STORMS AND LOCALLY HEAVY RAIN MAY OCCUR DURING THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT.

DONAVON

In the hours before

Special weather statement, Sep 18, 9:21 PM CDT, 1 hour 57 minutes before

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Local storm report, Sep 18, 10:54 PM CDT, 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1054 PM CDT SAT SEP 18 2010

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

1053 PM     HAIL             3 W BEDFORD             40.67N 94.78W
09/18/2010  E1.75 INCH       TAYLOR             IA   LAW ENFORCEMENT

            ON HIGHWAY 2

&&

BF

Local storm report, Sep 18, 11:16 PM CDT, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1116 PM CDT SAT SEP 18 2010

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

1108 PM     HAIL             6 NW DES MOINES         41.64N 93.69W
09/18/2010  E1.00 INCH       POLK               IA   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS QUARTER SIZED HAIL.

1110 PM     HAIL             4 NW DES MOINES         41.63N 93.67W
09/18/2010  E1.00 INCH       POLK               IA   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS QUARTER SIZED HAIL.

&&

LEE

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 18, 9:32 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	43 min
Sep 18, 10:14 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	46 min
Sep 18, 10:46 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass	44 min
Sep 18, 11:01 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold, Taylor	44 min
Sep 18, 11:30 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass	45 min
Sep 18, 11:45 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold, Taylor	45 min
Sep 19, 12:15 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Union	45 min
Sep 19, 12:28 AM CDT	Severe Thunderstorm Warning	DMX	Decatur, Ringgold	47 min
Sep 19, 12:40 AM CDT	Flash Flood Warning	DMX	Adams, Cass, Union	6 hr
Sep 19, 1:01 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Ringgold, Union	44 min
Sep 19, 1:16 AM CDT	Severe Thunderstorm Warning	DMX	Decatur	44 min
Sep 19, 1:21 AM CDT	Severe Thunderstorm Warning	DMX	Cass	39 min
Sep 19, 2:17 AM CDT	Flash Flood Warning	DMX	Decatur, Ringgold, Union, Wayne	5 hr
Sep 19, 2:27 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	48 min
Sep 19, 3:15 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Ringgold, Taylor	60 min
Sep 19, 9:02 AM CDT	River Flood Warning	DMX	Taylor	4 hr
Sep 19, 2:09 PM CDT	River Flood Warning	DMX	Appanoose, Wayne	16 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2010 Every severe thunderstorm warning in 2010

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.