Length of current heat wave is unusual

Friday will be the 10th consecutive day with a maximum temperate greater than 90 degrees in Decorah.  Decorah weather observer Richard Bernatz says it isn't often that a heat wave lasts that long

Bernatz has studied past temperature readings and has discovered that a heat wave of 10 or more consecutive days above 90 degrees has happened only 14 times since 1893.  The last such heat wave was 23 years ago--from July 2nd through July 11th in 1989.

There are two nominees for the worst heat wave in the last 125 years in Decorah: temperatures reached over 100 degrees on 14 consecutive days in 1936and temperatures stayed above 90 degrees for 25 days from June 14th through July 8th in 1910.