Flooding along the James River from earlier heavy rain and snow melt continued through all of May. Flooding was moderate to major, with only slow changes in the river stages.
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 episode as NWS FSD wrote it up.
Flooding along the James River from earlier heavy rain and snow melt continued through all of May. Flooding was moderate to major, with only slow changes in the river stages. The flooding affected farmland and pastureland, and caused continued closure of some roads.
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 Apr 30, 6:50 PM CST, 5 hours 10 minutes earlier.
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 750 PM CDT THU APR 30 2009 .DISCUSSION... UPDATED FCST AND GRID TO INCREASE CLOUD COVER SUBSTANIALLY ALONG AND N OF I90 WHERE SOLID AREA OF STRATUS IS LOCATED. ALSO WITH CLOUDS SPREADING INTO FAR SW QUICKER THAN PREV FCST...WL NEED TO INCREASE CLOUDS ACRS THE S A LTL QUICKER. DID INTRODUCE 20% AS FAR E AS SUX LATE TONIGHT AS PRECIP NOW MOVG INTO NW NEB/SW SD AND WL TRACK EWD ALONG AND S OF MO RVR LATER TONIGHT. FINALLY BUMPED UP TEMPS FOR TONIGHT DUE TO THE CLOUD COVER. && .AVIATION... GENLY VFR...WITH CIGS NR BKN-OVC040 N OF I90 THRU 08Z. VFR S OF I90 WITH CIGS AOB BKN080 AFTER 06Z. && .PREVIOUS DISCUSSION... MOISTURE WITH COOL AIR HAS BEEN MAKING SLOWER INROAD INTO NRN CWA THAN ERYR EXPECTED...WITH HEATG FAILING TO PRODUCE MUCH CU/SC BYND NRN EDGE. EXPECT SOME OF THE SC TO MAKE ITS WAY DOWN INTO NRN/ECNTRL FCST AREA NEXT SVRL HRS...THEN DCRS THIS EVE. MEANWHILE...WEAK WAVE APPCHG FROM SW WITH HI/MID CLDS JUST RECENTLY STARTING TO INCRS ON STLT OVER SRN WY/NRN CO...IS TARGETED BY MODELS TO KEEP MOST OF ITS LGT PCPN S OF FCST AREA. STILL EXPECT SOME INCREASE IN CLDS ESPLY SRN PART OF FCST AREA LATE TNGT...BUT LESS THAN BEFORE. WITH DRY AIR CONTG TO FILTER IN AT LR LVLS...EXPECT THAT SFC PCPN WILL HAVE TROUBLE FIGHTING IT NEWD INTO OUR CWA AND WILL CONFINE CHC MENTN TO ONLY THE EXTRM SWRN CRNR. AM KEEPING SOME INCRS IN CLDS ANYWAY BECAUSE OF TRAILING WEAK SHRTWVS MOVG ACRS ON A FRTHER NWD TRACK. SKIES SHUD BE CLEAR ENUF FOR TEMPS TO GET DOWN TO CLOSE TO FRZG NRN CWA LATE TNGT WITH LOWS RANGING UP TO ABOUT 40 FAR S. MODELS IN PRETTY GOOD AGREEMENT FOR THE FRIDAY THROUGH SUNDAY TIME FRAME. AS A HUDSON BAY LOW INCREASES IN STRENGTH...WEST TO NORTHWEST FLOW WILL INCREASE...WITH THE STRONGEST WINDS TO THE NORTHEAST OF THE CWA. REGARDLESS...DUE TO STRONG MIXING POTENTIAL WITH NEARLY UNIDIRECTIONAL WINDS...FRIDAY WILL BE BREEZY...WITH SATURDAY A LITTLE LESS SO AND SUNDAY EVEN LESS. ALL 3 DAYS LOOK DRY WITH CHANCES FOR PRECIPITATION CONFINED TO THE SOUTH OF THE AREA. SO...MAINLY HIGHS IN THE 50S ON FRIDAY AS WE SHAKE OFF THE REMNANTS OF THE COLDER AIR THAT HAS MOVED IN TODAY. BOTH SATURDAY AND SUNDAY WILL HAVE A LITTLE MORE MILD AIR ALOFT TO TAP INTO...LEADING TOWARDS WIDESPREAD 60S BOTH DAYS...SO A PLEASANT WEEKEND IN STORE. LOWS WILL GENERALLY BE IN THE 30S EACH MORNING. IN THE LATTER PERIODS(MON/THU)...THE MAIN FOCUS HERE WILL BE THE LONG WAVE PATTERN AND JUST HOW LONG IT TAKES TO SHAKE OFF THE EFFECTS OF THE HUDSON BAY LOW. A VERY STRONG HUDSON BAY LOW IS CURRENTLY DEVELOPING AND LOOKS TO HOLD STRONG THROUGH MUCH OF THE EXTENDED PERIOD. THIS GENERALLY SPELLS SOMEWHAT MIXY DAYS WITH MILD AND MOSTLY DRY WEATHER. THE MODELS CONTINUE TO HAVE TROUBLE ON DECIDING WHEN AND HOW TO BREAK DOWN THE HUDSON BAY LOW...BUT MOST INDICATIONS ARE THAT A STRONG WEST/EAST JET STREAK WILL WORK INTO THE CENTRAL ROCKIES AND THEN INTO THE CENTRAL PLAINS AROUND WEDNESDAY WHICH SHOULD PUSH THIS LOW TO THE NORTHEAST. THIS WILL BRING A BETTER CHANCE FOR RAIN AND THUNDERSTORMS AS WELL AS BRING IN ABOVE NORMAL TEMPERATURES. SO...WILL CONTINUE THE CHANCES FOR THUNDER DURING MUCH OF THE PERIOD...BUT AT THIS TIME IT LOOKS LIKE THE BEST CHANCES WILL BE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE MN...NONE. IA...NONE. NE...NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1018 AM CDT THU APR 30 2009 SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098- IAZ001>003-012>014-020>022-031-032-NEZ013-014-011200- 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- 1018 AM CDT THU APR 30 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA... SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA. .DAY ONE...TODAY AND TONIGHT FLOODING... FLOODING WILL CONTINUE ALONG THE JAMES RIVER INTO THE FIRST HALF OF MAY. THE RIVER CONTINUES TO SLOWLY RISE...AND THE CREST SHOULD MOVE ALONG THE RIVER FROM NORTH TO SOUTH IN THE FIRST HALF OF MAY. PLEASE SEE THE LATEST ISSUED FLOOD STATEMENTS FOR MORE DETAILED INFORMATION. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. && FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT WWW.WEATHER.GOV/SIOUXFALLS. THIS INCLUDES THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK. WILLIAMS
The national radar mosaic for the moment the first event began.
6 flood. Local standard time, as filed.
Moderate to major flooding continued along the James River. The river crested early in the month at 5.6 feet above flood stage at Huron on May 4th. The river then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded.
Moderate to major flooding continued along the James River. The river crested early in the month at 4.0 feet above flood stage near Forestburg on May 4th. The river then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded.
Moderate to major flooding continued along the James River. The river crested early in the month at 4.9 feet above flood stage at Mitchell on May 6th. The river then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded. Flooding of a mobile home area near the river in Mitchell slowly abated during the month.
Moderate to major flooding continued along the James River. The river crested early in the month, then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded.
Moderate to major flooding continued along the James River. The river crested early in the month, then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded.
Moderate to major flooding continued along the James River. The river crested early in the month at 4.0 feet above flood stage near Scotland. The river then began a very slow fall. Several roads remained closed, and pastureland and farmland along the river remained flooded.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2009Every state in 2009This day in weather historyWarnings in South Dakota, May 2009
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: 173627, 173645, 173652, 173656, 173660, 173663.