Alert archive / Iowa / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 166, NWS Des Moines, IA

May 22, 2004Clarke County, Decatur County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 22, 2004, 11:31 PM CDT for Clarke County, Decatur County, Iowa. It was in force for 44 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: May 22, 2004, 11:31 PM CDT (04:31 UTC)
Expired: May 23, 2004, 12:15 AM CDT
In force: 44 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

Counties Clarke County, IA, Decatur County, IA

The radar

The Des Moines radar (KDMX), 91 km from the middle of the area, began a volume at 04:31 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

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

Issued	Product	Office	Lasted
May 22, 6:15 PM CDT	Tornado Watch	SPC	6 hr
May 22, 10:40 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 4.5 hours before the alert went out and 218 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: 2882 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1091 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 260 m²/s²
Significant tornado parameter: 4.2
Supercell composite: 16.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

833 
WUUS53 KDMX 230431
SVRDMX
IAC039-053-230515-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1132 PM CDT SAT MAY 22 2004

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CLARKE COUNTY IN SOUTH CENTRAL IOWA
  DECATUR COUNTY IN SOUTH CENTRAL IOWA

* UNTIL 1215 AM CDT

* AT 1131 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS FROM 10 MILES NORTH OF MURRAY TO 24
  MILES WEST OF LAMONI...OR FROM 34 MILES SOUTHWEST OF DES MOINES TO
  77 MILES SOUTHWEST OF DES MOINES...MOVING EAST AT 50 MPH.

* SEVERE THUNDERSTORMS WILL BE...

  NEAR GRAND RIVER AROUND 1145 PM...
  NEAR OSCEOLA AROUND 1150 PM...
  NEAR LAMONI AROUND 1155 PM...
  NEAR LAMONI MUNICIPAL AIRPORT AROUND MIDNIGHT AND
  NEAR LEON AROUND 1205 AM.

HURRICANE FORCE WINDS OF 70 TO 80 MILES AN HOUR ARE LIKELY IN THE
WARNED AREA.

GO TO A BASEMENT OR SMALL INTERIOR ROOM. EXTENSIVE DAMAGE IS LIKELY.
EVACUATE MOBILE HOMES...AND SEEK SHELTER IN A STURDY BUILDING. SEVERE
STRAIGHT LINE WINDS CAN SOUND LIKE A TORNADO...AND PRODUCE SIMILAR
DAMAGE.

A TORNADO WATCH REMAINS IN EFFECT FOR THE AREA. REMEMBER...SEVERE
THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO WARNING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL MIDNIGHT SUNDAY MORNING FOR
IOWA.

LAT...LON 4115 9402 4088 9401 4060 9399 4059 9359
          4087 9358 4115 9360

$$

KULA

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 May 22, 2:09 PM CDT, 9 hours 22 minutes earlier.

Area forecast discussion, May 22, 2:09 PM CDT, 9 hours 22 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
209 PM CDT SAT MAY 22 2004

.DISCUSSION...
MAIN CONCERNS FOR EARLY IN THE FORECAST PERIOD WILL BE CONVECTION
THROUGH MONDAY. TODAY OUTFLOW BOUNDARY FROM MORNING CONVECTION
BEGINNING TO ERODE OVER NORTHERN MISSOURI WITH A MORE SOUTHERLY PUSH
BECOMING APPARENT. NEXT IN ROUND OF SHORTWAVES NOW ENTERING MIDWEST.
STATIONARY BOUNDARY OVER NORTHERN IOWA BEGINNING TO SAG SOUTH WITH
BOUNDARIES PRIMED TO CONVERGE. EXPLOSIVE THUNDERSTORM DEVELOPMENT
APPEARS LIKELY AND FROM 18Z OAX SOUNDING...CAP IS ERODING.
SUPERCELLS ARE LIKELY WITHIN THE FIRST SEVERAL HOURS OF INITIATION
LATE THIS AFTERNOON AND EVENING. LARGE HAIL AND TORNADOES WILL BE
THE MAIN THREATS EARLY ON. HEAVY RAIN WILL BE A CONCERN WITH THE
POSSIBILITY OF TRAINING STORMS EARLY. 65-70KT 850MB JET CRANKS UP
TONIGHT WITH GOOD CONVERGENCE OVER IOWA AND PLENTY OF MOISTURE FEED.
CONVECTION SHOULD FORM INTO AN MCS AND TRAVEL ACROSS THE
NORTHWESTERN 2/3 OF THE FORECAST AREA. WIDESPREAD 1-2 INCH AMOUNTS
LIKELY WITH LOCALLY HEAVIER POSSIBLE.  LOW TRACKS ACROSS CNTRL IA
SUNDAY...POSSIBLE THUNDERSTORMS DEVELOPING ALONG COLD FRONT ACROSS
EAST. MORE THUNDERSTORMS EXPECTED MONDAY AS NEXT SYSTEM ARRIVES.

ACTIVITY FINALLY COMES TO AN END BY TUESDAY WITH COOLER AND DRY
CONDITIONS EXPECTED. KEPT NEXT CHANCE FOR PRECIPITATION FRIDAY.
ENSEMBLES NOT IN AGREEMENT ON SHORTWAVE TOWARDS THE END OF THE WEEK
AND REMAIN CONSISTENT FOR END OF EXTENDED PERIOD.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...FLOOD WATCH TONIGHT NORTH OF
INTERSTATE 80.

&&

DONAVON

Hazardous weather outlook, May 22, 3:27 PM CDT, 8 hours 4 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
327 PM CDT SAT MAY 22 2004

IAZ004>007-015>017-024>028-036>039-048>050-060>062-231100-
BLACK HAWK-BREMER-BUTLER-CERRO GORDO-EMMET-FRANKLIN-GRUNDY-HAMILTON-
HANCOCK-HARDIN-HUMBOLDT-JASPER-KOSSUTH-MARSHALL-PALO ALTO-POLK-
POWESHIEK-STORY-TAMA-WINNEBAGO-WORTH-WRIGHT-
327 PM CDT SAT MAY 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MUCH OF CENTRAL AND NORTHERN
IOWA...NORTH AND EAST OF A LINE FROM EMMETSBURG...TO DES MOINES...TO
GRINNELL.

.DAY ONE...TONIGHT

THERE IS A MODERATE RISK OF SEVERE WEATHER FROM 6 PM TONIGHT
THROUGH THE REST OF THE NIGHT.  THREATS INCLUDE VERY LARGE HAIL AND
DAMAGING STRAIGHT LINE WINDS. ISOLATED TORNADOES ARE ALSO POSSIBLE
DURING THE EVENING HOURS. FLASH FLOODING IS ALSO POSSIBLE...
ESPECIALLY ACROSS AREAS ALONG AND NORTH OF HIGHWAY 20 THAT WERE HARD
HIT BY RECENT RAINS. ISOLATED 3 TO 5 INCH RAINFALL TOTALS ARE
POSSIBLE BY SUNDAY MORNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

A THUNDERSTORM COMPLEX...WITH SOME EMBEDDED SEVERE
THUNDERSTORMS POSSIBLE...WILL LIKELY BE ONGOING EARLY SUNDAY
MORNING. SEVERE WEATHER IS POSSIBLE AGAIN SUNDAY AFTERNOON AND
MONDAY AFTERNOON AND NIGHT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION WILL BE NEEDED TONIGHT FOR BOTH SEVERE WEATHER AND
FLOODING REPORTS. SPOTTER ACTIVATION MAY ALSO BE NEEDED AGAIN ON
SUNDAY AND MONDAY.

IAZ023-033>035-044>047-057>059-231100-
AUDUBON-BOONE-CALHOUN-CARROLL-CRAWFORD-DALLAS-GREENE-GUTHRIE-
POCAHONTAS-SAC-WEBSTER-
327 PM CDT SAT MAY 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A PORTION OF WEST
CENTRAL INTO CENTRAL IOWA...ALONG AND WEST OF A LINE FROM AUDUBON...
TO PERRY...TO POCAHONTAS.

.DAY ONE...TONIGHT

THERE IS A MODERATE RISK OF SEVERE WEATHER FROM 600 PM THROUGH
THE NIGHT. THREATS INCLUDE VERY LARGE HAIL AND DAMAGING STRAIGHT LINE
WINDS. CONDITIONS ARE ALSO VERY FAVORABLE FOR TORNADOES DURING THE
EVENING. FLASH FLOODING IS ALSO POSSIBLE...ESPECIALLY ACROSS AREAS
ALONG AND NORTH OF HIGHWAY 20 THAT WERE HARD HIT BY RECENT RAINS.
ISOLATED 3 TO 5 INCH RAINFALL TOTALS ARE POSSIBLE BY SUNDAY MORNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SEVERE THUNDERSTORMS ARE POSSIBLE MONDAY AFTERNOON AND NIGHT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED TONIGHT FOR BOTH SEVERE
WEATHER AND FLOODING REPORTS. SPOTTER ACTIVATION MAY ALSO BE NEEDED
MONDAY AFTERNOON AND NIGHT.

IAZ073>075-084>086-092>097-231100-
APPANOOSE-DAVIS-DECATUR-LUCAS-MAHASKA-MARION-MONROE-RINGGOLD-TAYLOR-
WAPELLO-WARREN-WAYNE-
327 PM CDT SAT MAY 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MUCH OF SOUTHERN IOWA.

.DAY ONE...TONIGHT

THERE IS A MODERATE RISK OF SEVERE WEATHER FROM 600 PM TONIGHT
THROUGH THE REST OF THE NIGHT.  THREATS INCLUDE VERY LARGE HAIL AND
DAMAGING STRAIGHT LINE WINDS.  CONDITIONS ARE ALSO FAVORABLE FOR
STRONG TORNADOES.  EVENING HOURS. ISOLATED FLASH FLOODING CANNOT BE
RULED OUT...BUT IS NOT LIKELY.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SEVERE THUNDERSTORMS ARE POSSIBLE SUNDAY AFTERNOON AND AGAIN
MONDAY AFTERNOON AND NIGHT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT. SPOTTER ACTIVATION MAY ALSO
BE NEEDED AGAIN ON SUNDAY AFTERNOON AND MONDAY.

IAZ070>072-081>083-231100-
ADAIR-ADAMS-CASS-CLARKE-MADISON-UNION-
327 PM CDT SAT MAY 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A PORTION OF SOUTHERN IOWA.

.DAY ONE...TONIGHT

THERE IS A MODERATE RISK OF SEVERE WEATHER FROM 600 PM THIS
EVENING THROUGH THE REST OF THE NIGHT.  THREATS INCLUDE VERY LARGE
HAIL AND DAMAGING STRAIGHT LINE WINDS. CONDITIONS ARE ALSO VERY
FAVORABLE FOR STRONG TORNADOES DURING THE EVENING. ISOLATED FLASH
FLOODING CANNOT BE RULED OUT...BUT IS NOT LIKELY.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SEVERE WEATHER IS POSSIBLE MONDAY AFTERNOON AND NIGHT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED TONIGHT. SPOTTER ACTIVATION
MAY ALSO BE NEEDED MONDAY AFTERNOON AND NIGHT.

In the hours before

Local storm report, May 22, 11:04 PM CDT, 27 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1104 PM CDT SAT MAY 22 2004

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

1100 PM     FLASH FLOOD      8 SE AMES               41.94N 93.52W
05/22/2004                   STORY              IA   EMERGENCY MNGR

            NUMEROUS ROADS CLOSED IN SOUTHERN STORY COUNTY DUE TO
            FLOODING.

&&

GRAMS

Local storm report, May 22, 11:08 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1108 PM CDT SAT MAY 22 2004

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

1105 PM     TSTM WND GST     GREENFIELD              41.31N 94.46W
05/22/2004  65 MPH           ADAIR              IA   EMERGENCY MNGR

            REPORTED BY EMERGENCY MANAGEMENT.

&&

SS

Local storm report, May 22, 11:12 PM CDT, 19 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1112 PM CDT SAT MAY 22 2004

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

1101 PM     TSTM WND DMG     1 S ANITA               41.43N 94.77W
05/22/2004                   CASS               IA   EMERGENCY MNGR

            DAMAGE REPORTED SOUTH OF ANITA. GRAIN BIN BLOWN APART.
            DOWNED TREES AND POWER LINE DOWNED THROUGHOUT THE COUNTY.
            REPORTED BY EMERGENCY MANAGEMENT.

&&

SS

Local storm report, May 22, 11:26 PM CDT, 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1126 PM CDT SAT MAY 22 2004

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

1105 PM     FLASH FLOOD      WATERLOO                42.49N 92.35W
05/22/2004                   BLACK HAWK         IA   EMERGENCY MNGR

            EXTENSIVE STREET FLOODING AT LEAST CURB HIGH...DEEPER IN
            SOME LOCATIONS.

&&

GRAMS

Local storm report, May 22, 11:29 PM CDT, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1129 PM CDT SAT MAY 22 2004

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

1057 PM     HAIL             5 SW ANITA              41.39N 94.83W
05/22/2004  1.00 INCH        CASS               IA   EMERGENCY MNGR

&&

GRAMS

Local storm report, May 22, 11:30 PM CDT, 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1130 PM CDT SAT MAY 22 2004

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

1120 PM     HEAVY RAIN       EVANSDALE               42.46N 92.28W
05/22/2004  3.25 INCH        BLACK HAWK         IA   TRAINED SPOTTER

            3.25 INCHES OF RAIN SINCE 10 PM.

&&

SS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 22, 7:00 PM CDT	Tornado Warning	DMX	Adair	30 min
May 22, 7:01 PM CDT	Tornado Warning	DMX	Adair	29 min
May 22, 7:04 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	26 min
May 22, 7:06 PM CDT	Tornado Warning	DMX	Polk, Story	54 min
May 22, 7:10 PM CDT	Tornado Warning	DMX	Dallas, Guthrie	50 min
May 22, 7:13 PM CDT	Flash Flood Warning	DMX	Boone, Story	92 min
May 22, 7:14 PM CDT	Tornado Warning	DMX	Audubon	31 min
May 22, 7:14 PM CDT	Tornado Warning	DMX	Greene, Guthrie	46 min
May 22, 7:23 PM CDT	Tornado Warning	DMX	Madison	37 min
May 22, 7:31 PM CDT	Tornado Warning	DMX	Guthrie	44 min
May 22, 7:49 PM CDT	Tornado Warning	DMX	Jasper, Marshall	56 min
May 22, 7:51 PM CDT	Tornado Warning	DMX	Dallas	39 min
May 22, 7:57 PM CDT	Tornado Warning	DMX	Story	33 min
May 22, 8:18 PM CDT	Tornado Warning	DMX	Polk	57 min
May 22, 8:21 PM CDT	Flash Flood Warning	DMX	Audubon, Boone, Carroll, Dallas, Greene, Guthrie and 4 more	16 hr
May 22, 8:29 PM CDT	Tornado Warning	DMX	Dallas	16 min
May 22, 8:31 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Guthrie	44 min
May 22, 8:41 PM CDT	Tornado Warning	DMX	Tama	49 min
May 22, 8:43 PM CDT	Tornado Warning	DMX	Marshall	47 min
May 22, 9:09 PM CDT	Tornado Warning	DMX	Polk, Story	36 min
May 22, 9:14 PM CDT	Tornado Warning	DMX	Dallas	31 min
May 22, 9:16 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	44 min
May 22, 9:27 PM CDT	Tornado Warning	DMX	Marshall, Tama	63 min
May 22, 9:31 PM CDT	Flash Flood Warning	DMX	Tama	15 hr
May 22, 10:00 PM CDT	Severe Thunderstorm Warning	DMX	Cass	45 min
May 22, 10:14 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	46 min
May 22, 10:22 PM CDT	Flash Flood Warning	DMX	Black Hawk	16 hr
May 22, 10:23 PM CDT	Severe Thunderstorm Warning	DMX	Polk, Story	52 min
May 22, 10:24 PM CDT	Severe Thunderstorm Warning	DMX	Adair	36 min
May 22, 10:46 PM CDT	Severe Thunderstorm Warning	DMX	Cass	29 min
May 22, 10:48 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	57 min
May 22, 10:55 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	50 min
May 22, 10:57 PM CDT	Severe Thunderstorm Warning	DMX	Adair	48 min
May 22, 11:09 PM CDT	Severe Thunderstorm Warning	DMX	Madison, Ringgold, Union	51 min
May 22, 11:20 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	55 min
May 22, 11:36 PM CDT	Severe Thunderstorm Warning	DMX	Polk, Warren	54 min
May 22, 11:54 PM CDT	Tornado Warning	DMX	Warren	36 min
May 23, 12:07 AM CDT	Tornado Warning	DMX	Jasper, Marion	53 min
May 23, 12:22 AM CDT	Severe Thunderstorm Warning	DMX	Lucas	23 min
May 23, 12:35 AM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Poweshiek	55 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2004 Every severe thunderstorm warning in 2004

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.