With one to four inches of liquid residing in the snowpack near and north of Interstate 90 at the start of the month, a more or less ideal melting of the winter snowpack in early March produced minor flooding along much of the middle portions of the Big Sioux River Basin.
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.
With one to four inches of liquid residing in the snowpack near and north of Interstate 90 at the start of the month, a more or less ideal melting of the winter snowpack in early March produced minor flooding along much of the middle portions of the Big Sioux River Basin.
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 8, 10:53 PM CST, 7 minutes earlier.
AREA FORECAST DISCUSSION National Weather Service Sioux Falls SD 1153 PM CDT Sun Mar 8 2020 .SHORT TERM...(This Evening through Monday Evening) Issued at 340 PM CDT Sun Mar 8 2020 Timing for the short wave and surface cold front appears on track, with the front moving through central South Dakota in the afternoon hours and passing by Huron at 3 PM. The breezy southerly winds will come to an end shortly before the front comes sweeping through, with the winds switching to a north-northwesterly direction. The cold air and breezy winds will create wind chill values dipping down into the mid-teens to lower 20s before sunrise, which will be an unwelcome change for most with temperatures near freezing. Focus for the precipitation tomorrow morning has shifted south, with areas from Sioux City to Storm Lake now looking at less than a tenth of an inch, with lesser amounts northwards. Any measurable precipitation is most likely going to be rain, with a slight chance of some freezing rain if cold air makes it south quicker than expected towards sunrise. As the front is pulled out of the area by the shortwave, clouds will be clearing along with it allowing us to warm up to at least normal temperatures on Monday. .LONG TERM...(Tuesday through Sunday) Issued at 340 PM CDT Sun Mar 8 2020 With the upper atmosphere transitioned to zonal flow, another shortwave is expected to pass over the area Tuesday afternoon. Ahead of the wave, light snow is possible for areas north of I-90, with amounts generally under half an inch. As temperatures warm in the afternoon, the transition to light rain will take place. As the shortwave arrives, best chances for precipitation shift towards southeastern SD and northwest IA, which could see around a quarter of an inch of rain. Split flow aloft leads to skies mostly clearing out on Wednesday, with high temperatures remaining about 10 degrees above average through the remainder of the work week. Models have the southerly component of the split flow hinting at bringing up a system from the Gulf of California to usher in the weekend, but much uncertainty remains. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1146 PM CDT Sun Mar 8 2020 Cold front has moved through this evening, bringing in MVFR and IFR ceilings across the region. Winds have remained gusty, between 20 and 30 knots. Some locations are observing mist, dropping visibility into the MVFR category for a time. Precipitation is still possible Monday morning, with the best chances still far southeastern SD and northwestern IA. With cooler temperatures, some mixed precip is possible. However, there could be snow late in the morning across east- central SD. Confidence in this occurring at KFSD is low enough to keep mention out of TAFs. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && SHORT TERM...Trellinger LONG TERM...Trellinger AVIATION...SG
Hazardous Weather Outlook National Weather Service Sioux Falls SD 423 AM CDT Sun Mar 8 2020 IAZ012-020>022-031-032-NEZ013-014-SDZ050-057-063>071-091100- Sioux-Plymouth-Cherokee-Buena Vista-Woodbury-Ida-Dixon-Dakota- Gregory-Brule-Charles Mix-Douglas-Hutchinson-Turner-Lincoln- Bon Homme-Yankton-Clay-Union- 423 AM CDT Sun Mar 8 2020 This Hazardous Weather Outlook is for northwest Iowa, west central Iowa, northeast Nebraska, south central South Dakota and southeast South Dakota. .DAY ONE...Today and tonight. Breezy southerly winds with gusts up to 35 mph combined with low humidity will lead to high to very high fire danger this afternoon and evening. Well above average temperatures through Sunday will accelerate remaining snowpack melt, leading to rises on some area streams and rivers. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Hazardous weather is not expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. IAZ001>003-013-014-MNZ071-072-080-081-089-090-097-098-SDZ038>040- 052>056-058>062-091100- Lyon-Osceola-Dickinson-O'Brien-Clay-Lincoln-Murray-Cottonwood-Nobles- Jackson-Pipestone-Rock-Beadle-Kingsbury-Brookings-Jerauld-Sanborn- Miner-Lake-Moody-Aurora-Davison-Hanson-McCook-Minnehaha- 423 AM CDT Sun Mar 8 2020 This Hazardous Weather Outlook is for northwest Iowa, southwest Minnesota, central South Dakota, east central South Dakota, south central South Dakota and southeast South Dakota. .DAY ONE...Today and tonight. Well above average temperatures through Sunday will accelerate remaining snowpack melt, leading to rises on some area streams and rivers. .DAYS TWO THROUGH SEVEN...Monday through Saturday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
3 flood. Local standard time, as filed.
The Big Sioux River at Brandon (gage site BBSS2) crested 1.23 feet above flood stage on March 15. Significant flooding of agricultural lands occurred upstream and downstream of Brandon.
The Big Sioux River above Hawarden (gage site HWDI4) crested 0.35 feet above flood stage on March 10. Minor flooding of agricultural land occurred near the river.
The Big Sioux River at Akron (gage site AKRI4) crested 0.33 feet above flood stage on March 11. Some rural roads and agricultural lands near the river were flooded.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2020Every state in 2020This day in weather historyWarnings in Iowa, March 2020
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: 875511, 875513, 875515.