Sioux storm history

Rainfall amounts across Sioux County from June 20-22 ranged from 2 to 7 inches, with the highest amounts across the northern half of the county. Farther north and upstream, up to 12 inches of rain fell across portions of southeast South Dakota and northwest Iowa. This rainfall re…

As snow developed and began to accumulate during the evening on January 14, the increase in winds to a sustained 30 to 40 mph, with a few gusts as high as 51 mph at an Iowa Department of Transportation site at Alton and 44 mph near Maurice (SXK), resulted in widespread near white…

Snow accumulated 5 to 8 inches. Increasing northwest winds during the event caused wind chills to approach 20 below zero as the snow was ending. The winds also caused a few areas of blowing and drifting snow. A vehicle accident which caused 2 fatalities and 3 injuries was attribu…

Thunderstorm winds flipped over a camper, twisted swing sets, blew down power poles, and caused widespread tree damage. Several trees were blown down, including one which fell on a tent, killing a participant in a bicycle ride across Iowa. Several roads were blocked by fallen tre…

Water ponding in the area of Central Park overflowed roadways and entered the Sioux Center Fire Department building. Two homes suffered the collapse of basement walls from the high water. Water also inundated a transformer which cut off power to seven homes in the northwest part …

An extended period of precipitation began with freezing rain quickly producing heavy ice accumulations, ranging up to between a quarter and half inch. The precipitation then changed to sleet and then snow, with sleet and snow accumulations reaching 5 inches at Rock Valley. Many b…

Two episodes of extended blizzard conditions occurred over a slightly less than 24 hour period, with a slight improvement in conditions during the mid-afternoon to early evening. Gusty northwest winds from 35 to 45 mph were concurrent with light to moderate snowfall, which totale…

Sustained winds reached around 40 to 45 mph with a gust as high as 61 mph near Maurice.

Periods of light snowfall along with winds of 40 to 60 mph resulted in periods of whiteout conditions. Travel was not recommended during the early and mid-afternoon. A two-vehicle, three-injury accident occurred 1 mile west of Boyden when low visibility resulted in a rear-end col…

Snowfall totaled 4.0 inches in Rock Valley, 3.3 inches in Hull, and 3.1 inches in Orange City.

Wind chills reached as low as -32 degrees near Maurice and -28 degrees at Hawarden.

Synoptic northwest winds were occasionally sustained from 40 to 50 mph with gusts as high as 64 mph at an Automated Weather Observing System site near Maurice.

Snowfall totaled 8.5 inches at Rock Valley, 7.0 inches 2 miles southeast of Sioux Center, and 6.1 inches at Orange City.

A long-duration snowfall totaled 10.0 inches at Sioux Center, 7.7 inches at Rock Valley, and 6.7 inches in Orange City.

Sustained winds reached 40 to 47 mph at times with a peak gust of 61 mph at an Automated Weather Observing System site near Maurice.

Snowfall totaled 4.5 inches 6 miles north of Ireton, 4.0 inches at Sioux Center, 3.3 inches at Orange City, and 3.0 inches at Rock Valley.

Dangerous heat index values peaked as high as 112 degrees at Hawarden and 106 degrees at Orange City on August 16.

Dangerous heat index values peaked as high as 108 degrees at Hawarden and 104 degrees at Sioux Center.

As a result of intense rainfall, the Floyd River near Struble rose nearly 8 feet in 3 hours to flood stage.

The Floyd River at Alton rose above flood stage on the evening of July 30th, cresting around 1.46 feet above flood stage (13.46 ft) on July 31st. The river then fell below flood stage on the afternoon of July 31st.

Iowa Highway 60 near 480th Street was closed due the roadway being flooded by a couple feet of flowing water.

Runoff from heavy rainfall caused the Floyd River at Alton to rise 5 feet in less than 3 hours, resulting in a brief period over flood stage.

Trees were knocked down by thunderstorm wind gusts.

Thunderstorm wind gusts knocked down a tree with a roughly 5 foot diameter. The tree appeared at least partially rotted from photos.

Thunderstorm winds ripped a live 2 to 3 foot diameter tree limb down.

Numerous trees were knocked down by thunderstorm wind gusts.

Large limbs were torn from trees by thunderstorm wind gusts.

Thunderstorm wind gusts were measured by a personal weather station.

An extended period of damaging thunderstorm wind gusts were measured by a personal weather station, with a peak of 99 mph measured at 2039 CST.

An extended period of damaging thunderstorm wind gusts were measured by a personal weather station, with a peak of 92 mph at 2036 CST.

A 61 mph thunderstorm wind gust was measured at Sioux County Regional Airport (KSXK).

Numerous trees were knocked down by thunderstorm wind gusts.

On the east side of town, an enclosed trailer was flipped on its side by thunderstorm wind gusts.

Significant building damage occurred at the lumber yard in Alton.

Two barns were destroyed by thunderstorm wind gusts. Numerous power poles were down along with trees uprooted.

Thunderstorm wind gusts were measured by a personal weather station.

A 58 mph wind gust was recorded at the Sioux County Regional Airport.

Thunderstorm wind gusts were measured by a personal weather station.

Dangerous heat index readings reached an afternoon peak on July 27 as high as 119 degrees at Hawarden, 113 degrees near Hull and Sioux Center, and 108 degrees near Maurice.

Dangerous heat index readings reached afternoon peaks as high as 108 degrees at Hawarden and 107 degrees in Sioux Center on July 23.

Thunderstorm winds measured at Sioux County Airport.

Winds were measured by a personal weather station.

Numerous large tree limbs were downed by thunderstorm wind gusts. Several large empty water tanks were blown into the cemetery.

Daily afternoon and evening heat indices ranged from 105 to 115 degrees with a maximum heat index of 115 degrees at a personal weather station in Hawarden, 111 degrees in Hull, 110 degrees in Sioux Center, and 105 degrees near Maurice on June 20.