Runoff from snow melt along with periods of rainfall through mid March caused minor flooding along portions of the Little Sioux River. Minor flooding occurred at Linn Grove (LNNI4) impacting mainly lowland agricultural locations and the city park in Sioux Rapids.
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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.
Runoff from snow melt along with periods of rainfall through mid March caused minor flooding along portions of the Little Sioux River. Minor flooding occurred at Linn Grove (LNNI4) impacting mainly lowland agricultural locations and the city park in Sioux Rapids.
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 Mar 19, 5:23 PM CST, 1 hour 37 minutes earlier.
Area Forecast Discussion National Weather Service Sioux Falls SD 623 PM CDT Mon Mar 19 2018 .SHORT TERM...(This evening through Tuesday) Issued at 327 PM CDT Mon Mar 19 2018 Light precipitation in south central SD will slowly spread eastward this afternoon and evening, as a minor trough digs eastward across the northern Plains. Patchy drizzle this afternoon will changing over to light rainfall this evening, however as temperatures fall into the lower to mid 30s, rain will change over to light snow. This change over will occur quickest in south central SD into the highway 14 corridor, including the Buffalo Ridge area. The entire forecast area will switch to primarily snowfall by late this evening or the early morning hours. Light snow will continue to slowly track east across the region into Tuesday, exiting areas west of I-29 by midday, and northwest Iowa and southwest Minnesota by late afternoon. Without a great deal of lift or forcing seen with this system, precipitation will remain on the light side, however the relatively long duration of this event will lead to a widespread 1 to 3 inches of accumulations. With temperatures falling into upper 20s to lower 30s, snow ratios will not be particularly high. The highest amounts are expected in the higher terrain of the Buffalo Ridge, where around 3 or locally 4 inches will be possible. Fortunately, forecast soundings do not support freezing rain or sleet, so icing concerns are minimal. Northerly winds will also be light for the duration for this event. .LONG TERM...(Tuesday night through Monday) Issued at 327 PM CDT Mon Mar 19 2018 A weak trailing shortwave follows closely behind, diving across east central SD and southwest MN Tuesday night. This wave weakens as it arrives, with the lower level moisture holding on. Not seeing much of any saturation in the dendritic growth zone, so expect precipitation to be drizzle or freezing drizzle for areas mainly north of I-90. This activity will be light and very spotty, so do not expect any icing concerns. Stratus begins clearing from southwest to northeast Wednesday and Wednesday evening as upper level ridging builds across the Plains. Temperatures will once again be on warming trend Wednesday and Thursday, reaching the mid 40s to mid 50s Thursday. The active weather pattern makes a return late this week. An initial wave lifts across the area late Thursday night into Friday, bringing primarily a cold rain to region. Temperatures are a little more questionable in southwest MN and east central SD, where there will be a greater potential for seeing snowfall, but this will be dependent on the timing of the precipitation, and whether it will hold off in this area until later Friday. Main wave digs across the Four Corners region Friday night, tracking through the central Plains on Saturday. Models are coming into somewhat better agreement in this feature, with the ECMWF trending more similar to the GFS with a colder pattern. With clouds and precipitation spreading across the area, went ahead and lowered highs on Saturday into the upper 30s to upper 40s, with temperatures likely to struggle to warm through the day. Still a lot of uncertainty with this system, with temperatures likely to be near freezing. Any slight change in track and temperature profiles will result in a primarily rain event or snow event. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 616 PM CDT Mon Mar 19 2018 Ceilings and visibilities will fall into the IFR range from west to east overnight as a slow moving band of snow moves through. Conditions have deteriorated at KHON as of 00Z, and expect condition to deteriorate in the I-29 corridor from 03-06Z from north to south. Improving condition are expected around 12Z at KHON, and towards 18Z for both KSUX and KFSD. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && SHORT TERM... LONG TERM... AVIATION...BT
Hazardous Weather Outlook National Weather Service Sioux Falls SD 424 AM CDT Mon Mar 19 2018 IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ038>040-050-052>071-200930- Lyon IA-Osceola-Dickinson-Sioux-O'Brien-Clay IA-Plymouth-Cherokee- Buena Vista-Woodbury-Ida-Lincoln MN-Lyon MN-Murray-Cottonwood- Nobles-Jackson-Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury- Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora- Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-Hutchinson- Turner-Lincoln SD-Bon Homme-Yankton-Clay SD-Union- 424 AM CDT Mon Mar 19 2018 This Hazardous Weather Outlook is for portions of northwest Iowa, west central Iowa, southwest Minnesota, northeast Nebraska, central South Dakota, east central South Dakota, south central South Dakota, and southeast South Dakota. .DAY ONE...Today and Tonight An area of light rain mixed with snow will develop west of the James River through the day. Any rain will change to snow as this precipitation moves east across the region tonight. Light snow accumulations of 1 to 3 inches will be possible tonight into Tuesday morning, with the highest amounts expected in higher elevations of southwest Minnesota. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday A chance of rain and snow will impact the region Friday into the upcoming weekend. While some areas could see accumulating snow, there is too much uncertainty in the track of this system, as well as in associated temperatures, to determine snowfall amounts at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
The national radar mosaic for the moment the first event began.
3 flood. Local standard time, as filed.
Runoff from snow melt along with periods of rainfall through mid March caused minor flooding of lowland agricultural areas along portions of the Little Sioux River. The river reached a crest of 0.9 feet above flood stage near Linn Grove (gage site LNNI4) on March 20.
Runoff from snow melt along with periods of rainfall through mid March caused minor flooding of lowland agricultural areas along portions of the Little Sioux River. The river reached a crest of 0.9 feet above flood stage near Linn Grove (gage site LNNI4) on March 20.
Runoff from snow melt along with periods of rainfall through mid March caused minor flooding of lowland agricultural areas along portions of the Little Sioux River. The river reached a crest of 0.9 feet above flood stage near Linn Grove (gage site LNNI4) on March 20.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2018Every state in 2018This day in weather historyWarnings in Iowa, March 2018
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: 759885, 759890, 759891.