July was second hottest ever

There’s no doubt that July was one of the hottest months in recorded history, especially in the West.

As of Tuesday morning, July 31, the Spokane International Airport’s average temperature for July of 2007 (including high and low temperatures) was 75.8 degrees. This is 7.2 degrees above normal, which ranks as the second-warmest July in recorded history. The hottest July occurred in 1906 with an average temperature of 75.9 degrees. Last month, there were 16 days at or above 90 degrees with two days over 100 degrees. It was 101 on July 5th and the 13th.

The normal average high temperature for July is 82.5 degrees. As of July 31, the average reading of 89.9 degrees ranks as the sixth highest. The warmest July, in terms of the highest temperature, occurred in 1960 with an average of 91.5 degrees.

There was record heat and dryness across much of the Western U.S. last month, with wildfires breaking out in all 11 states. Based on current weather patterns, August’s weather may not be quite as hot as July’s.

According to scientists at the National Climatic Data Center, the January-through-June 2007 period was the second-warmest across the globe in recorded history. Last winter was also the mildest worldwide. The South Pole just experienced its warmest June ever.

Believe it or not, an all-encompassing heat wave that covered the entire U.S. occurred during the hottest summer, at least in modern times, was in July and August of 1936. Those months were considered to be the peak of the infamous “Dust Bowl Days.” July and August of 1936 saw temperatures nationwide soar to levels that haven’t been matched since.

Fifteen states still have all-time record maximum temperature marks set in 1936 that stand today despite the current cycle of warming. Killer-type readings of 120 degrees or higher were observed in July 1936 in Arizona, Arkansas, California, Kansas, Oklahoma, South Dakota, Texas and as far north as North Dakota. On July 6, 1936, the mercury peaked at 121 degrees at Steele, N.D.

The height of the all-time record U.S. heat wave occurred on July 15, 1936, when the average high temperature in Iowa, for example, 108.7 degrees. That was slightly hotter than the average July afternoon in the broiling Desert Southwest of southeastern California, Arizona, Nevada and New Mexico.

This hottest July ever in the nation’s heartland also resulted in the region’s worst drought. Total rainfall in July of 1936 was just 8 percent to 14 percent of normal across much of the Central U.S.

As far as the near-term weather is concerned, warmer- and drier-than-normal conditions will be likely across the region in early August. I still expected to see some scattered late afternoon and evening thunderstorms, especially toward the middle of the month. Although readings will be very warm in August, it shouldn’t be as hot as the torrid July of 2007.

If La Niña, the cooler-than-normal sea-surface temperature event in the south-central Pacific Ocean, continues to maintain its intensity over the next few months, this fall will be a big contrast to our recent weather. Based on current patterns, this upcoming season may start a bit ahead of schedule and be cooler and wetter than average. Stay tuned.