River levels from the historic June flooding remained above flood stage for some locations into July, although continued a declining trend.
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.
River levels from the historic June flooding remained above flood stage for some locations into July, although continued a declining trend.
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 Jun 30, 9:57 PM CST, 2 hours 3 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Sioux Falls SD 1057 PM CDT Sun Jun 30 2024 .KEY MESSAGES... - Rivers across the area have crested, with a slow downward trend in river levels as dry conditions continue. - Well below normal temperatures (~10 deg F) continue into Monday, and remain a touch below normal (0-5 deg C) Tuesday through Thursday as well. - Monday and especially Monday night will be the next chance for severe weather and heavy rain. Higher confidence in showers and storms (80-90+%), with chances for more than an inch of rain in northwest IA and southwest MN (70-80%), and low chances for 2 inches (20-30%) by Tuesday morning. - Stronger westerly flow aloft continues through the end of the week, resulting in a couple chances for rain. && .DISCUSSION... Issued at 316 PM CDT Sun Jun 30 2024 With the surface high pressure now off to our east, southeasterly return flow is advecting warmer air back into the region, albeit temperatures remain firmly below normal. Temperatures as of the early afternoon hours are in the upper 60s to lower 70s, with only a couple extra degrees added before the sun starts to go down. Areas along and west of the James River Valley have been seeing increased cloud coverage due to some weak isentropic lift, low instability, and moderate moisture in the mid-levels, but this activity is expected to remain as ACCAS and not form as measurable precipitation. Overnight into Monday, a surface low pressure is expected to develop over the western Dakotas as a mid-level shortwave ejects onto the central plains. Out ahead of the main wave, warm-air advection (WAA) combined with weaker shortwaves are expected to create our first round of scattered showers and thunderstorms prior to daybreak. High resolution models show a north to south oriented scattered group of storms moving up from eastern Nebraska, moving across far eastern South Dakota and Nebraska throughout the morning hours. That round of rain will be dissipating as it moves into portions SW Minnesota and NW Iowa during the early afternoon hours, with amounts looking to remain on the lighter side as probabilities for half an inch are in the 20-30% range. Expect a lull in rainfall activity before the main upper level wave begins to move into the area during the late afternoon, with rain chances returning during the evening hours further aided by the warm front moving towards the area. Severe weather wise, we'll need to see how the earlier round of convection influences the environment, as some models keep the big push of instability behind the warm front from reaching our area. The western push in south-central South Dakota looks like it has the highest chance of reaching our area, though again most models keep the instability away from our area, and if a storm were to form in that environment golf ball sized hail would be possible out of the 2- 3kJ/kg of CAPE along with gusts to 60mph from 40 to 50 knots of predominantly speed shear. While severe weather chances are looking to trend down, the possibility of heavy rainfall returns overnight into Tuesday as the main wave moves through further aided by the warm and cold front. Given 200-1000 J/kg of MUCAPE in addition to precipitable water values at the maximum of climatology according to the ensemble situational awareness tables, rainfall rates will likely be fairly efficient at 1 to 2 inches per hour. Furthermore, the ESATs highlight integrated water vapor transport towards the NE/IA border, which is at the 99th percentile of climatology, further raising concern for efficient rainfall rates. Overall by Tuesday morning, expecting a widespread swath of half an inch to an inch for areas southeast of a line from Marshall, MN to Sioux Falls, SD to Tyndall, SD, with localized totals across portions of NW Iowa and SW Minnesota of 2-4 inches possible. Probabilities for an inch of rain are at 50-80% SE of the aforementioned line, dropping to 10-30% for 2 inches, and very isolated chances for 3 inches. Given the wet antecedent conditions across the flood prone areas, flash flooding cannot be ruled out, with further rises on local streams and rivers also possible. WPC has placed the region in a slight risk for excessive rainfall (level 2 out of 4). Scattered showers and thunderstorms decrease in coverage Tuesday morning, though we will likely see another round of rain as the cold front moves out of the area during the afternoon hours. We'll have to see where the cold front ends up being Tuesday morning, but chances for severe weather return in the afternoon out ahead of the cold front given 2-3kJ/kg of MUCAPE and 40-50 knots of 0-6km bulk shear. Again this would lead to chances for golf ball sized hail and gusts to 60 mph. Can't rule out additional heavy rain given the continued climatologically high precipitable water values, but the integrated water vapor transport has decreased to just above the 90th percentile of climatology. After a dry and warm start for the day with temperatures near normal on Wednesday, chances for light rain return during the afternoon hours continuing into Thursday. Another chance Thursday night into Friday as a low pressure moves eastwards off to our north, but some models indicate that we may end up remaining dry as we get dry slotted. Upper level ridging builds along the southwest throughout the weekend, but guidance is no longer as convinced as some ensemble members show the ridging is short lived. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1057 PM CDT Sun Jun 30 2024 Southeast winds increase quickly after sunrise by 12Z, with frequent gusts 25-35kt through the day. Winds will subside slightly after sunset Monday evening, though occasional gusts 20-25kt will linger through the end of the TAF period. MVFR-locally IFR ceilings are expected to expand across the area Monday morning, accompanied by areas of rain/isolated thunder. A second round of showers and storms develops in the evening, with heavier rain favored from northeast Nebraska into northwest Iowa. May also see localized visibility restrictions at times in areas with moderate to heavy rain. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && DISCUSSION...APT AVIATION...JH
Hazardous Weather Outlook National Weather Service Sioux Falls SD 412 AM CDT Sun Jun 30 2024 IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ038>040-050-052>071-010915- Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee- Buena Vista-Woodbury-Ida-Lincoln-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-Bon Homme- Yankton-Union- 412 AM CDT Sun Jun 30 2024 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 Flooding will continue to slowly recede over the next several days. .DAYS TWO THROUGH SEVEN...Monday through Saturday Showers and thunderstorms are expected to develop on Monday with stronger thunderstorms more likely on Monday night. A few severe storms will be possible with hail to the size of golf balls and wind gusts to 60 mph. The other concern will be heavy rain with 1 to 2 inches of rain possible. The better chance for this will be far southeast South Dakota, northeast Nebraska and northwest Iowa. Additional showers and thunderstorms will be possible throughout the week. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
16 flood. Local standard time, as filed.
Flooding continued from June on Spirit Lake near Orleans, with declining lake levels. The lake fell below flood stage on the afternoon of July 4th.
Flooding continued from June on West Okoboji Lake near Milford, with declining lake levels. The lake fell below flood stage on the evening of July 14th.
Flooding continued from June on the Ocheyedan River near Spencer, with declining river levels. The river fell below flood stage on the evening of July 1st.
Flooding continued from June on the Little Sioux River near Montgomery, with declining river levels. The river fell below flood stage on the afternoon of July 2nd.
Flooding continued from June on the Little Sioux River near Milford, with declining river levels. The river fell below flood stage on the morning of July 8th.
Flooding continued from June on the Little Sioux River near Milford, with declining river levels. The river fell below flood stage on the morning of July 8th.
Flooding continued from June on the Little Sioux River above Spencer, with declining river levels. The river fell below flood stage on the afternoon of July 17th.
Flooding continued from June on the Little Sioux River at Spencer, with declining river levels. The river fell below flood stage on the morning of July 18th.
Flooding continued from June on the Little Sioux River at Linn Grove, with declining river levels. The river fell below flood stage on the afternoon of July 2nd.
Flooding continued from June on the Little Sioux River at Linn Grove, with declining river levels. The river fell below flood stage on the afternoon of July 2nd.
Flooding continued from June on the Little Sioux River at Cherokee, with declining river levels. The river fell below flood stage on the afternoon of July 7th.
Flooding continued from June on the Little Sioux River at Cherokee, with declining river levels. The river fell below flood stage on the afternoon of July 7th.
Flooding continued from June on the Big Sioux River near Brandon, with declining river levels. The river fell below flood stage on the morning of July 4th.
Flooding continued from June on the Big Sioux River at Hawarden, with declining river levels. The river fell below flood stage on the morning of July 5th.
Flooding continued from June on the Big Sioux River at Akron, with declining river levels. The river fell below flood stage on the morning of July 6th.
Flooding continued from June on the Big Sioux River near Richland, with declining river levels. The river fell below flood stage on the morning of July 7th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2024Every state in 2024This day in weather historyWarnings in Iowa, July 2024
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: 1199928, 1199929, 1199931, 1199932, 1199933, 1199934, 1199935, 1199936, 1199938, 1199939, 1199940, 1199941, 1199942, 1199943, 1199944, 1199945.