— NWS Indianapolis (@NWSIndianapolis) June 20, 2017
Source: Howard County Historical Society.
1957: An F5 tornado cut a swath through Fargo, North Dakota killing 10 and injuring at least 103 people. This tornado was the northernmost confirmed F5 tornado until the Elie, Manitoba tornado on June 22, 2007.
A look back on the 45th anniversary of Hurricane “Agnes.” pic.twitter.com/GX8aZ7kCr5
— NWS MARFC (@NWSMARFC) June 20, 2017
1989: A meteorological “hot flash” hit Pierre, South Dakota. Descending air from collapsing thunderstorms caused the temperature in Pierre to warm from 86 degrees at midnight to 96 at one a.m. and to 104 at 2 a.m. Pierre’s record high for the date of 105 degrees in 1974.
1970: Nesbyen, Norway reached 96 degrees on this day, becoming the warmest temperature recorded in Norway.
2001: Large hail driven by strong thunderstorm winds raked Denver International and front-range airports. Wind gusting to 54 mph along with hail as large 2 inches in diameter punched at least 14 thousand holes and cracks in the flat roofs of several buildings at Denver International Airport. Also, 93 planes and hundreds of cars were damaged. About 100 flights had to be canceled stranding 1500 travelers. The Airport was completely shut down for about 20 minutes. The storm also damaged ground avoidance radar used to track planes on the ground to prevent collisions. Damage was estimated at 10 million dollars not counting the damage to the 93 airliners. The storm moved south and struck Watkins Colorado with hail as large as 2 1/2 inches in diameter and winds gusting to 60 mph.