River levels already high from excessive rains during late June received another push upward from heavy rainfall on July 1-3. Rainfall from one to two inches was common upstream in the basin.
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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.
River levels already high from excessive rains during late June received another push upward from heavy rainfall on July 1-3. Rainfall from one to two inches was common upstream in the 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 Jul 3, 9:37 PM CST, 4 hours 23 minutes earlier.
Area Forecast Discussion National Weather Service Sioux Falls SD 1037 PM CDT Tue Jul 3 2018 .SHORT TERM...(This evening through Wednesday) Issued at 321 PM CDT Tue Jul 3 2018 A few different potential issues/concerns over the next 24 to 36 hours as we head into/thru the Independence Day holiday. For the rest of today, warm and humid conditions continue to drive heat index values into the 90s and near 100 degrees in locations west of the I-29 corridor. Heat Advisory still looks ok and will expire at 8 pm as scheduled. By this evening, the low level front running from south central SD northeastward into west central MN will be the focus for thunderstorm development. While it looks like most of initial thunderstorm activity should remain west of the MO River and north of Hwy 14, outside of our coverage area, ample instability would support a severe threat. Deep layer 0-6 km bulk shear values continue to be very meager, only around 15-20 kts, and thus storms will struggle to organize although still would carry a large hail and wind threat with thick CAPE profiles in the hail growth zone and DCAPE values over 1000 J/kg. Another concern with convection that fires this evening is where cold pool driven propagation may carry any convection overnight. Several high-res CAMs suggest the potential that convection will make its way south, perhaps back into SW MN which saw significant flash flooding this morning. Given the lack of deep layer shear, can't rule out a cold pool expanding well beyond the initial convection but am hesitant to put too much stock in the CAMs given their performance over the last couple of weeks. SREF QPF plumes also shed question on any rainfall potential over this area with the majority of members only a few tenths of an inch or less. Regardless, any rainfall could be impactful over the flood impacted area and so have raised POPs into the chance range for SW MN and will monitor for trends through the evening. WPC has placed locations north of I-90 in a Slight Risk of excessive rainfall. Independence Day will again bring warm and humid conditions to the region along with thunderstorm chances. Both of these topics are also somewhat uncertain pending overnight convection. Expect there will be at least some convective debris in our coverage area Wednesday morning which may impact temperatures, depending on how long it stick around. Current temperature forecast puts portions of our CWA, namely NW IA and surround areas, near or above Heat Advisory criteria but will hold off on issuing until the above mentioned concerns are better resolved. Expect heat index values in the 90s, perhaps higher, for your holiday afternoon celebrations. The main thunderstorm chances are expected with the passage of a cold front during the afternoon and evening hours. The air mass ahead of this front will be very unstable with SBCAPE values around 4000-5000 J/kg. Deep layer 0-6 km bulk shear values are once again generally weak which will dampen storm organization. Additionally, fairly unidirectional shear profiles would support upscale growth as the evening progresses. With the progged instability profiles, certainly a severe threat present, although perhaps dampened somewhat by the previously mentioned deep layer shear profiles. Thunderstorm chances increase by the late afternoon and very well could play havoc with holiday festivities. .LONG TERM...(Wednesday night through Tuesday) Issued at 321 PM CDT Tue Jul 3 2018 Thankfully, front continues to drive south of the area Wednesday night and Thursday morning, taking with it the precipitation chances. This will also push the hot and humid air mass south of the region with highs within a few degrees of 80 for Thursday. Upper level ridge builds to our west and will allow for a couple days of dry weather and slowly warming temperatures. By Sunday, a jet streak passes by to our north, and along with a flattened ridge, could bring some precipitation chances by late weekend and early into next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1031 PM CDT Tue Jul 3 2018 Latest model runs keep much of the thunderstorm activity out of our area overnight, though cannot rule out a stray thunderstorm in the vicinity of KHON. A low level jet will develop across the region tonight, though it appears that the main jet axis will remain to the west of our area, and any low level wind shear would be marginal at TAF sites, so did not include in the TAFs. A boundary will push across the area on Wednesday, bringing a better chance of thunderstorms, especially in the afternoon, and a few of these could be severe. Winds will transition from southerly to northerly on Wednesday afternoon and evening with the passage of the front. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && SHORT TERM...Kalin LONG TERM...Kalin AVIATION...JM
Hazardous Weather Outlook National Weather Service Sioux Falls SD 742 PM CDT Tue Jul 3 2018 SDZ038>040-050-052>061-063>066-068-069-050045- Beadle-Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake- Moody-Brule-Aurora-Davison-Hanson-McCook-Charles Mix-Douglas- Hutchinson-Turner-Bon Homme-Yankton- 742 PM CDT Tue Jul 3 2018 This Hazardous Weather Outlook is for portions of central South Dakota, east central South Dakota, south central South Dakota, and southeast South Dakota. .DAY ONE...Tonight There is a chance of thunderstorms generally north of I-90 tonight. Initially, a few storms could be strong to severe with the threat gradually transitioning to a locally heavy rain threat as the evening/overnight progresses. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Heat indices between 90 and 100 degrees are expected for 4th of July afternoon. The chance of storms will increase during the late afternoon and evening on Wednesday, with a few strong to severe storms, as well as locally heavy rain possible. .SPOTTER INFORMATION STATEMENT... Spotter activation is not likely tonight. IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ062-067-070-071-050045- 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-Minnehaha-Lincoln SD- Clay SD-Union- 742 PM CDT Tue Jul 3 2018 This Hazardous Weather Outlook is for portions of northwest Iowa, west central Iowa, southwest Minnesota, northeast Nebraska, and southeast South Dakota. .DAY ONE...Tonight There is a small possibility of thunderstorms generally north of I-90 tonight. If they do develop, a few storms could be strong to severe with the threat gradually transitioning to a locally heavy rain threat as the evening/overnight progresses. Moderate to major flooding continues on several rivers and streams. For specific river details, visit https://water.weather.gov. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Heat indices around 100 degrees are again expected for 4th of July afternoon. The chance of storms will increase during the late afternoon and evening on Wednesday, with a few strong to severe storms, as well as locally heavy rain possible. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed through tonight.
The national radar mosaic for the moment the first event began.
3 flood. Local standard time, as filed.
Significant amounts of crop and pasture land near the Rock River were impacted by minor flooding as river levels climbed to 2.7 feet above flood stage near Hardwick (gage site HRDM5) on July 4.
Significant amounts of crop and pasture land near the Rock River were impacted by minor flooding as river levels climbed to 2.7 feet above flood stage near Hardwick (gage site HRDM5) on July 4.
Significant amounts of crop and pasture land near the Rock River were impacted by minor flooding as river levels climbed to 0.3 foot above flood stage near Luverne (gage site LUVM5) on July 5.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2018Every state in 2018This day in weather historyWarnings in Minnesota, July 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: 772868, 772871, 772874.