The hot weekend of June 17-18, 1995 began one of the most intense, prolonged June heat waves in recent years. A tremendous upper-air ridge developed over the central U.S. and reached its peak intensity during the weekend (Image 1 above). On Saturday, June 17 the temperature at the National Weather Service (NWS) near Negaunee rose to 92 degrees. The next day, it topped out at a sizzling 96. Both of these high temperatures were records. Across the rest of the U.P., a string of record-highs were achieved. Multiple days above 90 degrees in the Upper Peninsula are rather rare. This occurred in mid-June 1995 even in the Copper Country. The Houghton County Airport (CMX) near Calumet set five consecutive records starting June 16. The hottest temperature in that stretch was 93 on June 18. Before that, it reached 92 for three-straight days. In Iron Mountain record highs above 90 degrees were set from June 17-20 including a 100-degree high on the 18th. This was the first 100-degree high at that location since August 1955.
This heat wave contributed greatly to the warmest June on record at the NWS (Image 2). The mean temperature of 66.3 was 7.1 degrees above average. While the rest of the summer of ??95 remained warm, the second half of June was, by far, the hottest part of the season.