A strong low pressure brought multiple rounds of strong to severe thunderstorms to portions of central Iowa on Tuesday, April 16th, 2024. Elevated thunderstorms developed overnight and lingered into the morning across the area, remaining sub severe.
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 DMX wrote it up.
A strong low pressure brought multiple rounds of strong to severe thunderstorms to portions of central Iowa on Tuesday, April 16th, 2024. Elevated thunderstorms developed overnight and lingered into the morning across the area, remaining sub severe. This was followed by a second line of storms that lifted into the area by late morning. This line produced a few tornadoes in southwest to central Iowa. This was then followed by a third round of thunderstorms, more discrete in storm mode, that produced a few more tornadoes in northwest portions of Iowa. At least 8 short-lived tornadoes touched down, some causing damage in portions of central Iowa from late morning through the afternoon. A few of the severe thunderstorms also produced hail of 1 to 2 inches in diameter and wind gusts of 50-60 mph. Environmental winds behind the dry line were quite strong as well, occasionally gusting in excess of 50-55 mph.
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 Des Moines, IA wrote its last area forecast discussion before the first event at Apr 15, 10:52 PM CST, 3 hours 58 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Des Moines IA 1152 PM CDT Mon Apr 15 2024 ...Updated for the 06z Aviation Discussion... .KEY MESSAGES... - Slight risk for severe weather southwest tonight with hail and wind being the primary threat. Storms lifespan will be short. - Enhanced risk of severe weather across the east tomorrow with two rounds of storms. All modes of severe weather possible. Heavy rainfall expected with up to 4 inches of rain in the northeast. - Cooling temperatures beyond with rain chances Thursday. Below freezing lows return at the end of this week. && .DISCUSSION... Issued at 334 PM CDT Mon Apr 15 2024 A closed upper level disturbance currently in the Desert Southwest will eject into the Plains later today, negatively tilting and deepening as it moves across Nebraska. At this point in the system's evolution, it will be stacked and remain at roughly the same heights while impacting the state. The pressure gradient will be tight across the state, have issued a Wind Advisory across the north for environment winds. A wide open Gulf will push moisture advection through the midlevel dry slot and northward this evening and overnight as the LLJ picks up. With near max percentile PWATs and multiple rounds, heavy rainfall will occur. The HREF Probability Matched Mean has amounts totaling over an inch for the entire area. Portions of northern and northeast Iowa will see all three rounds of convection and therefore the most rainfall. HREF paints localized areas of over 4 inches. This will be right over the region of the state with the worst drought conditions and can take the rain, but localized urban impacts are still possible. Round One, overnight convection: This round's evolution will impact what will transpire in the upcoming rounds. The LLJ will nose into western Iowa, generally over the location of the surface warm front which will be draped over southwest Iowa. While the dry slot will inhibit midlevel moisture, isentropic upglide will build in low level moisture which will have some thermodynamics at its disposal. The gradient of the main instability axis will hug the Missouri river with MUCAPE exceeding 1000J outstretched along the warm front. Shear in the lowest 3km will increase through the nighttime hours, but nocturnal profiles will not be supportive of anything surface based. Isolated severe hail will be possible due to the instability profile, but weaker shear profiles will limit the organization and lifespan of storms. The low center will drift northeast through the morning and pull the LLJ and morning convection northward. Main uncertainty is coverage of storms overnight. The greater the coverage, the less instability available for the next round. Round Two, morning/midday convection: A front with a trailing dry line will surge into the state early Tuesday morning and begin to occlude with the warm front in northwest Iowa. The upper level jet will veer into northern MO, keeping stronger 0-6km layer shear and divergence south. For central Iowa, the low level shear is more concerning. 0-3km shear will be approaching 50kts and will be out of the SSW. CAMs illustrate this round being a QLCS. Examining hodographs, 0-1km SRH values are approaching 300 m2/sec2 and 0-0.5km will be in the 200s. With LCLs very low, tornadoes are certainly in play. The questionable factor is the available instability for the line, especially at a capacity for the line to be surface based. Not only will there have already been a first round of rain and storms overnight, but stratiform rain will run ahead of the QLCS in the shear dominant environment, eating away at the available instability for the line. Round Three, afternoon/evening convection: On the heels of the second wave of convection will be the dry line and will feature the last round of potential thunderstorms. This round will be conditional on recovery of the near storm environment and afternoon guidance is keying in on on this being a possibility despite the short spacing in between. Historically, we have seen quick recoveries with little to no clearing between rounds (eg. 1999, 2001). The orientation of the stratiform rain from the earlier round aids in recovery of instability, but the position of the left exit region over the area may allow for updrafts to fester. In this round, favorable deep layer shear is present near the IA-MO border, so storms that get going can get organized and produce at least severe winds and some hail. There is uncertainty in the tornado potential with this round due to the questionable characteristics of the low level profile. Hodographs in the low levels lose arching characteristics, but can be more favorable if winds back. The better severe weather potential will be in the high shear environment in northern Missouri where less convection has overrun the environment. Long term: The closed low will then phase into a broader area of troughing by midweek. There will be another opportunity for precipitation on Thursday as frontogenesis sets up across the state. Northwest flow sets in through the rest of the week and pushes highs back into the 50s. Zonal midlevel flow will keep us dry through the rest of the week. Cool temperatures will lead to below freezing conditions for lows into the weekend and may warrant frost/freeze headlines. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1152 PM CDT Mon Apr 15 2024 Multiple rounds of showers and thunderstorms are expected to impact the terminals through much of the TAF period. The first round is expected to push through just after 06z from southwest to northeast through around 12z, with hail remaining a main hazard. Following the first round of storms, some brief drying is expected before another round pushes across the state between 15-18z through much of the afternoon, with large hail and a few tornadoes possible, especially over south and central Iowa. Lingering shower and storm chances are expected through the afternoon before gradually tapering off into the evening. With these showers and storms, low clouds and periods of lower visibilities are possible at times with heavier downpours, with MVFR/IFR remaining likely at times, especially through Tuesday morning into the afternoon. Winds generally are expected to increase through the day, with highest gusts through the morning into the afternoon out of the southwest around 30-35 knots. LLWS early on is also expected at times through this morning, and again mainly over southeast Iowa late in the TAF period. && .DMX WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 7 AM to 7 PM CDT Tuesday for IAZ004>007- 015>017-024>028-036>039. && DISCUSSION...Jimenez AVIATION...Bury
Hazardous Weather Outlook National Weather Service Des Moines IA 712 PM CDT Mon Apr 15 2024 IAZ004>007-015>017-024>028-036>039-161100- Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo- Humboldt-Wright-Franklin-Butler-Bremer-Hamilton-Hardin-Grundy- Black Hawk- 712 PM CDT Mon Apr 15 2024 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Tonight Thunderstorms will be likely later tonight. A few storms may be severe with large hail the primary concern. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday A Wind Advisory is in effect for the area. Please refer to the National Weather Service website at weather.gov/desmoines for further details. Additional thunderstorms can be expected Tuesday and Tuesday night with a Marginal to Slight Risk of severe weather. Large hail, damaging winds, and a few tornadoes will all be possible, along with locally heavy rains. .SPOTTER INFORMATION STATEMENT... Spotters may be needed at times tonight through Tuesday evening. IAZ023-033>035-044>050-057>062-070>075-081>086-092>097-161100- Pocahontas-Sac-Calhoun-Webster-Crawford-Carroll-Greene-Boone- Story-Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek- Cass-Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas- Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis- 712 PM CDT Mon Apr 15 2024 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Tonight Thunderstorms will be likely later tonight. A few storms may be severe with large hail the primary concern. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Additional thunderstorms can be expected Tuesday and Tuesday evening with a Slight to Enhanced Risk of severe weather. Large hail, damaging winds, and a few tornadoes will all be possible, along with locally heavy rains. .SPOTTER INFORMATION STATEMENT... Spotters may be needed at times tonight through Tuesday evening.
The Des Moines radar (KDMX), 77 km away, was scanning. The volume nearest the first event began at 08:50 UTC.
9 tornado, 6 hail, 2 thunderstorm wind, 1 lightning. Local standard time, as filed.
A small fire was started at a hotel in Pella after sustaining a lightning strike in the very early morning hours of April 16th.
This was a brief tornado which occurred west of Bedford moving due north just west of Highway 2 in Taylor County. This tornado did some low end damage to outbuildings before dissipating.
A small tornado occurred north of Carbon, IA and was captured on video. This produced EF0 damage to a house with some missing shingles along with damage to a few different outbuildings.
Tornado developed in Lake Anita State Park producing EF1 tree damage. The tornado moved northwest through a small subdivision producing EF0 damage then crossed the Crestwood Hills Golf Course before dissipating.
Local media reported penny sized hail on the northeast side of Chariton. Time estimated by radar.
A tornado occurred with morning convection as it moved north through central Iowa. This tornado began west of Dallas Center a moved north impacting a few farmsteads with mostly minor damage. This tornado produced a TDS on radar and lifted to the northeast of Minburn.
Delayed report of hail at the airport. Time estimated by radar.
Livestock building sustained damage during structural repair. Time estimated by radar.
Video from storm chaser provided footage for entire life cycle of tornado. The tornado formed just northwest of the hamlet of Rands and produced EF1 damage to telephone poles. The tornado traveled almost due north along Quinton Avenue and passed east of the Rockwell City Correctional Faciliity. It crossed old Highway 20 near Quinton Avenue and passed through a farmstead with only minor damage. The tornado eventually lifted after passing over a railroad.
Delayed report, time estimated by radar.
Report via mping.
A storm chaser caught video of this weak tornado south of Manson. It was a brief tornado which moved northward in open rural farmland. No damage indicators were impacted by this tornado, hence the EFU rating.
Storm chaser had video of entire life cycle of tornado. The tornado developed on the edge of a farmstead producing minor tree damage. The tornado continued northeast through rural farmland before turning northwest. The tornado remained in open farmland for the remainder of its path before dissipating.
This tornado was captured on video as it moved northward through rural farmland south of Rolfe. The tornado did not impact any damage indicators, hence the EFU rating.
A storm chaser captured video of this brief tornado as it moved just east of Rolfe. The tornado produced some minor damage to a couple of farmsteads on the east side of Rolfe along with some tree damage.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2024Every state in 2024This day in weather historyThe tornado archive for Iowa, 2024Warnings in Iowa, April 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: 1171170, 1169923, 1169928, 1169934, 1170746, 1169947, 1170747, 1170748, 1170750, 1169948, 1170751, 1170753, 1169949, 1169950, 1170754, 1169951, 1169952, 1170755.