Yankton storm history

Daily afternoon and evening heat indices ranged from 100 to 115 degrees with a maximum heat index of 115 degrees at Automated Weather Observing System site KYKN at Yankton on August 21. A direct fatality occurred in Yankton on the third day of excessive heat when a child was left…

Two brothers, age 19 and 17, were struck by lightning while swimming in Lewis and Clark Lake. The 19 year old died later the same day, while the 17 year old survived his injuries.

Flooding continued from August, but the James River near Yankton (YNNS2) soon fell below flood stage on September 4. However, excessive rainfall of 4 to 8 inches upstream September 10-12 (7.54 inches at Mitchell and 7.21 inches 7 miles south of Parkston) led to a rapid rise and a…

Continued precipitation with high water levels damaged county and township roadways during April. 260 miles of gravel roads were reported completely unusable at times during the month.

Street flooding in numerous intersections within the city of Yankton. A high number of flooded basements also reported, especially along Marne Creek. Other flooding resulted in extensive damage to public infrastructure including numerous county and township roads, culverts, and s…

Large hail up to golf ball size, driven by strong to damaging winds, caused widespread property and crop damage in and near Yankton. Numerous windows were broken, both in structures and in vehicles, roofs and siding were damaged in several homes and businesses, and trees were str…

Large hail, accompanied in places by damaging winds, destroyed or severely damaged crops in an area up to 10 miles wide from northwestern to southeastern Yankton County. Estimates from the Farm Service Agency were at least 48 thousand acres of corn, soybean, and alfalfa crops tha…

Large hail broke windows, damaged vehicles, and damaged trees.

Northwest winds were sustained between 40 and 52 mph at times, with gusts as high as 63 mph at Yankton and 2 miles west-southwest of Gayville, and 58 mph 10 miles north of Yankton.

Snowfall totaled 4.0 inches at Yankton and 3.5 inches 6 miles west of Yankton.

Wind chills reached as low as -31 degrees 2 miles west-southwest of Gayville and -28 10 miles north of Yankton.

Synoptic northwest winds were sustained from 40 to 48 mph with a peak gust of 64 mph at a South Dakota Road Weather Information System site 2 miles west-southwest of Gayville and 58 mph 12 miles north of Yankton.

Snowfall totaled 3.5 inches 2 miles east of Yankton.

A long-duration snowfall totaled 7.0 inches at Yankton.

Sustained winds periodically reached 40 to 44 mph at a South Dakota Road Weather Information System site near Gayville with a peak gust of 59 mph. An Automated Weather Observing System site at Yankton measured sustained winds up to 44 mph.

Dangerous heat index values peaked as high as 105 degrees 6 miles south-southwest of Utica on August 16.

Dangerous heat index values peaked as high as 105 degrees 6 miles south-southwest of Vermillion, 103 degrees at Yankton, and 101 degrees 1 mile west-southwest of Gayville.

Thunderstorm wind gusts were measured by a Road Weather Information System sensor near Gayville.

Thunderstorm wind gusts were measured by a personal weather station.

Dangerous heat index readings reached an afternoon peak as high as 112 degrees at Yankton, 111 degrees near Gayville, and 110 degrees 6 miles south-southwest of Utica.

Dangerous heat index readings reached daily afternoon peaks as high as 111 degrees 6 miles south-southwest of Utica on July 21.

Measured by a personal weather station. The first severe gust of 61 mph occurred at 1836 CST, followed by 66 mph gust at 1841 CST.

Severe wind gusts began at 1739 CST with a peak gust of 68 mph at 1745 CST.

Several large tree limbs were reported down in Yankton.

A 61 mph wind gust was measured at the South Dakota Road Weather Information System site near Gayville.

Quarter-size hail damaged crops.

Hail varying from pea to quarter size lasted 15 minutes.

An extended period of severe wind gusts was measured by a personal weather station, with the peak wind gust at 2219 CST.

Daily afternoon and evening heat indices ranged from 105 to 109 degrees with a maximum heat index of 109 degrees at the Road Weather Information System site near Gayville and 107 degrees at the Automated Weather Observing System site in Yankton on June 21.

Hail varied from nickel to quarter size.

Sustained easterly winds reached 30 to 39 mph with gusts as high as 45 mph at Yankton.

Thunderstorm wind gust measured by a personal weather station.

A 62 mph thunderstorm wind gust was measured by the South Dakota Road Weather Information System site near Gayville.

Northwest winds gusted up to 58 mph near Gayville.

Severe (D2) drought conditions improved to moderate (D1) late month.

Winds were sustained at 30 to 38 mph with a peak gust of 50 mph near Gayville and 47 mph at Yankton.

The lowest wind chills ranged from 35 to 37 below zero with 37 below zero observed at the Chan Gurney Municipal Airport (KYKN) near Yankton.

Snowfall totaled 3.6 inches 2 miles east of Yankton.

Severe (D2) drought conditions persisted through the month.