The temperature rose to a record-shattering 102 degrees in Iron Mountain on July 25, 1955. The heat was pumped up by a huge, hot upper-level high pressure system that covered much of the eastern half of the country (Image 1 above).
The summer of 1955 saw consistent, hot, muggy weather over a good share of the country (Image 2). This summer was known for its persistent nature. At the same time, the extremely high mean temperatures during July and August 1955 suggest high nighttime low temperatures. There also was a lack of drought accompanying the heat through most of the country except for portions of the central and southern Plains.
A 100-degree temperature is a relatively rare phenomenon in Iron Mountain. Since the 1930s, the mercury has hit 100 or above 10 times. By far the most occurred during the hot first half of July 1936. From the 7th through the 13th, it hit 100 or above six times. The last 100-degree temperature was recorded on June 18, 1995.
While no readings even approached 100, last week was the warmest stretch of this summer. There were four consecutive days with highs above 90 degrees in Iron Mountain, including a high of 94 on Tuesday, July 16. While it was hot, last summer was toastier. There were four days in June 2012 with highs of 90 or above and 10 days in July including 95-degree highs on the 5th and 16th. There was also an impressive stretch of four consecutive 90-degree days from July 2-5, 2012.
Heat will seem a distant memory this weekend. A cold upper-air trough is still forecast to settle into Upper Michigan beginning tomorrow. The chill will reach its nadir Saturday when highs over portions of the north may struggle to get much above 50 degrees. The average high is still in the mid to upper 70s. The coldest high temperature recorded in July at the National Weather Service (NWS) near Negaunee is 51 degrees. This mark was set on July 1, 1992 and then again on both July 6 & 7, 2004. Houghton??s coldest July high of 49 was also set in that cold summer of 1992.