3 thunderstorm wind, as filed by the National Weather Service.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sioux Falls, SD wrote its last area forecast discussion before the first event at Sep 15, 2:35 AM CST, 2 hours 10 minutes earlier.
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 335 AM CDT CDT WED SEP 15 2004 .DISCUSSION.. MAIN SHORT TERM FORECAST PROBLEMS ARE ONGOING WEATHER TODAY AND ITS IMPACTS ON TEMPERATURES AND FOG POTENTIAL TONIGHT. 07Z WATER VAPOR IMAGERY INDICATED STRONG SHORTWAVE TROUGH ENTERING WESTERN NEBRASKA WITH STRONG H300 DIFFLUENCE AHEAD OF FEATURE. WIDESPREAD PRECIP WAS SEEN ON MOSAICS BOTH ALONG THE COLD FRONT AND WARM FRONT. MODELS ALREADY BEGAN TO DIVERGE WITH HANDLING OF THIS FEATURE IN THE FIRST SIX HOURS OF THE FORECAST WITH GFS SEEMING TO BE A BIT CONVECTIVELY CONTAMINATED. EXPECT WAVE TO SLOW A BIT OVER THE NEXT FEW HOURS AS IT INTERACTS WITH FRONTAL ZONE AND CYCLOGENESIS INCREASES. THAT BEING SAID BEST SHOT OF PRECIP AFTER 12Z LOOKS TO BE IN THE NORTHEAST CWA...WITH PRECIP CHANCES DROPPING OF FAST TO THE SOUTH AFTER 13Z. ALTHOUGH THE RAIN WILL CONTINUE A BIT LONGER TODAY WONT CONTINUE FLOOD WATCH AS HEAVIEST RAINS HAVE ALREADY FALLEN...AND WILL JUST HAVE TO COVER THINGS WITH WARNINGS AS NEED BE. WAVE LOOKS TO CLEAR ENTIRE CWA AND STRONG SUBSIDENCE SETS IN. THIS SHOULD SCOUR OUT CLOUDS PRETTY QUICKLY SAVE FOR SOME WRAP AROUND STRATUS TO THE NORTHEAST. TEMPS SHOULD MIX OUT TO H850 PRETTY EASY IN THE SOUTH WITH LOTS OF SUNSHINE AND POST FRONTAL WIND...BUT WILL PROBABLY ONLY BE A FEW DEGREES WARMER THAN NOW IN THE NORTHEAST. TONIGHT SFC RIDGE SETTLES OVER AREA DROPPING OF WINDS. WITH ABUNDANT LOW LEVEL MOISTURE...INVERSION STRENGTHENING BY LL WARM ADVECTION AND WEAK BL WINDS...EXPECT TO SEE A GOOD RADIATIONAL FOG EVENT OVERNIGHT. DENSE FOG WILL ALSO BE POSSIBLE ACROSS THE SE AS WEAKEST WINDS WILL OCCUR AT TIME OF MAX RADIATIONAL COOLING. DESPITE GOOD COOLING...THINK MODELS ARE UNDER DOING SFC MOISTURE AND WILL GO NOT AS COLD AS GUIDANCE. AFTER THURSDAY MORNING WX SHOULD BE QUIET THROUGH SATURDAY. MODELS CONTINUE TO SHOW A SERIES OF SHORTWAVES SLIDING CROSS THE AREA THU-SAT. BUT SFC RIDGE TO THE SOUTH WILL SERIOUSLY IMPEDE ANY DECENT MOISTURE RETURN SO WILL CONTINUE DRY FORECAST. DID ADD SOME SMALL POPS ON SUNDAY AS STRONGER RETURN FLOW SETS UP...BUT MADE NO MAJOR CHANGES TO REST OF THE FORECAST. .FSD...WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. NE...NONE. IA...NONE. && JRM
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 541 AM CDT WED SEP 15 2004 SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098- IAZ001>003-012>014-020>022-031-032-NEZ013-014-161200- AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-BUENA VISTA IA- CHARLES MIX-CHEROKEE IA-CLAY-CLAY IA-COTTONWOOD MN-DAKOTA NE- DAVISON-DICKINSON IA-DIXON NE-DOUGLAS-GREGORY-HANSON-HUTCHINSON- IDA IA-JACKSON MN-JERAULD-KINGSBURY-LAKE-LINCOLN-LINCOLN MN- LYON IA-LYON MN-MCCOOK-MINER-MINNEHAHA-MOODY-MURRAY MN-NOBLES MN- OBRIEN IA-OSCEOLA IA-PIPESTONE MN-PLYMOUTH IA-ROCK MN-SANBORN- SIOUX IA-TURNER-UNION-WOODBURY IA-YANKTON- 541 AM CDT WED SEP 15 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA... SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS... SCATTERED THUNDERSTORMS ARE POSSIBLE THROUGH THE MORNING HOURS. THESE STORMS ARE NOT EXPECTED TO BECOME SEVERE. FLOODING... ALTHOUGH THE HEAVIEST RAIN HAS ENDED ACROSS THE AREA. LOW LAND FLOODING MAY STILL OCCUR ACROSS NORTHWEST IOWA AND SOUTHWEST MINNESOTA DUE TO RECENT RAINFALL. RIVERS AND STREAMS WILL APPROACH BANK FULL CONDITIONS TODAY AND PEOPLE IN THIS AREA SHOULD STAY ALERT FOR FURTHER RIVER STATEMENTS. WIND AND FOG... A RIDGE OF HIGH PRESSURE WILL SETTLE OVER THE REGION TONIGHT CAUSING CLEAR SKIES AND LIGHT WINDS. THESE CONDITIONS...COMBINED WITH MOISTURE WILL CAUSE AREAS OF FOG TO DEVELOP EAST OF THE JAMES RIVER VALLEY OVERNIGHT. FOG MAY BECOME LOCALLY DENSE WITH VISIBILITIES BELOW A HALF OF A MILE. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT. && FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT WWW.CRH.NOAA.GOV/FSD. THIS INCLUDES THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK.
The Sioux Falls radar (KFSD), 146 km away, was scanning. The volume nearest the first event began at 10:44 UTC.
3 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds uprooted trees, blew off the top of a 100 foot silo, and blew down a chicken pen.
Thunderstorm winds caused tree and power line damage. The damage resulted in a power outage that lasted two and a half hours and affected over a thousand city households, about a third of the city's population.
Thunderstorm winds caused tree damage at a cemetery, and moved a 20 inch tombstone 36 feet.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2004Every state in 2004This day in weather historyWarnings in Iowa, September 2004
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5424524, 5424525, 5424602.