Lyon storm history

Rainfall amounts across Lyon County from June 20-22 ranged from 7 to 12 inches. Widespread overland flooding ensued with additional major to record flooding along the Big Sioux, Rock, and Little Rock Rivers, and Mud Creek. At the peak of flooding, approximately 50 people were eva…

Flooding resulted in extensive damage to public infrastructure including numerous county and township roads, culverts, and some bridges.

Repeated heavy rains caused record flooding of the Rock River. Numerous homes, businesses, roads, farmland, and other low areas were flooded, forcing many people to evacuate their homes and rely on Red Cross and other volunteer assistance for several days. The flooding was especi…

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 6 inches at Rock Rapids. Many b…

Very heavy rain caused flash flooding, forcing streams including the Kanaranzi River, Rio Grand, and Moon Creek to overflow and flood homes, garages, and storage sheds in George. Flooding of roads and other lowlands was widespread. A road washed out and at least four bridges were…

Intermittent short duration near-blizzard conditions occurred, divided by a longer improvement in conditions as falling snow ended for a time during the late afternoon and evening. Gusty northwest winds from 35 to 45 mph were concurrent with light snowfall, which totaled 1.7 inch…

Sustained winds reached around 40 mph at Larchwood.

Periods of light snowfall along with winds of 40 to 55 mph resulted in periods of whiteout conditions. Travel was not recommended during the early and mid-afternoon.

Wind chills reached as low as -30 degrees at Larchwood and -26 degrees 4 miles southwest of George.

Snowfall totaled 3.5 inches 1 mile north-northeast of Larchwood and 2.3 inches in Rock Rapids.

Synoptic northwest winds were occasionally sustained from 40 to 46 mph with gusts as high as 70 mph at a personal weather station near Little Rock, 63 mph at Rock Rapids, and 60 mph in Larchwood.

Snowfall totaled 6.0 inches at Rock Rapids.

A long-duration snowfall totaled 8.2 inches at Rock Rapids.

Sustained winds reached 30 to 38 mph at times at a personal weather station in Larchwood.

Snowfall totaled 4.1 inches near Larchwood.

Heat index values peaked as high as 102 degrees 4 miles southwest of George on August 15 and 100 degrees 5 miles south-southwest of Ellsworth and at Larchwood on August 16.

Heat index values peaked as high as 103 degrees 5 miles south-southwest of Ellsworth and 102 degrees 4 miles southwest of George.

A tornado track was identified in corn fields using drone images. Other than the narrow convergent path in the corn, there were no damage indicators to determine a rating. The average path width was 20 yards.

Thunderstorm wind gusts were measured by a personal weather station.

Thunderstorm wind gusts were measured by a personal weather station.

An outbuilding was damaged by thunderstorm wind gusts with debris blown to the east. Several trees were uprooted in and near Alvord.

Thunderstorm winds dented one mostly full grain bin on the west side and collapsed a second empty bin.

Tree limbs up to 3 inches in diameter were downed by thunderstorm winds.

Thunderstorm winds destroyed an empty grain bin with debris blown west to east. Several large tree limbs were downed through the town of George.

Thunderstorm wind gusts were measured by a personal weather station.

Dangerous heat index readings reached an afternoon peak on July 27 as high as 116 degrees 4 miles southwest of George, 114 degrees 5 miles south-southwest of Ellsworth, and 110 degrees near Larchwood.

Dangerous heat index readings reached afternoon peaks as high as 113 degrees 5 miles south-southwest of Ellsworth and 4 miles southwest of George on July 23.

Daily afternoon and evening heat indices ranged from 105 to 116 degrees with a maximum heat index of 116 degrees at a personal weather station near George on June 20 and 109 degrees at Larchwood on June 21.

Winds were measured by a personal weather station.

Winds were measured by a personal weather station.

Several trees were downed by thunderstorm wind gusts.

A roof was blown off a hog barn.

Thunderstorm winds blew down several trees in Rock Rapids.

A cattle barn was significantly damaged by thunderstorm winds.

A machine shed and empty grain bin were destroyed by thunderstorm winds, which also tipped over a semi-truck.

Hail of various sizes fell, many with flat tops.

Hail varied from dime to quarter size.

Sustained easterly winds reached 45 to 53 mph with gusts as high as 72 mph 4 miles east of Lester, 63 mph 4 miles east of Rock Rapids, 63 mph at Rock Rapids, and 62 mph at Larchwood. Significant damage was reported with numerous large trees down in Alvord, Doon, and Rock Rapids.

An extended period of gusty winds reached speeds as high as 68 mph 4 miles east of Lester, 61 mph 2 miles east of Lester, and 59 mph at several locations near Rock Rapids. Multiple trees were downed in Alvord.

Hail was as large as ping-pong to golf ball size.

Snowfall totaled 3.9 inches at Inwood, 3.5 inches 1.2 miles north-northeast of Larchwood, and 3.3 inches at Rock Rapids.

Winds were sustained from 30 to 36 mph with a peak gust of 56 mph near Rock Rapids.