Our region finally got a good taste of summer last weekend as temperatures soared into the 80s in many areas on Sunday. The high at the airport was 79 degrees. Although we will still see occasional rain showers through the rest of this month, the overall trend points to warmer and drier conditions here in the Inland Northwest.
When summer arrives in full force, I still expect around 25 days at or above 90 degrees at the Spokane International Airport. As mentioned last week, the airport normally receives 19 days with highs at or above 90 degrees.
It’s also possible that we’ll see one or two days at or above the 100-degree mark. Over the last 20 years, Spokane averages about one day each summer with readings at or above 100. Our best chance to observe temperatures that warm would be around the full moon lunar cycle in late July and early August.
The hottest temperature recorded in Spokane was 108 degrees. It happened on July 26, 1928, and again on Aug. 4, 1961. The earliest date of 100 degrees in a season was June 22, 1973. The latest date that a 100-degree reading was observed was Aug. 31, 1967. A record six consecutive days of 100-degree or higher readings occurred July 23-28, 1928.
According to the National Weather Service, since 1990, temperatures at or above 100 degrees have been recorded in fewer than half of the summers (nine out of 20). Last year, the airport’s hottest day, Aug. 1, was 101 degrees.
Many folks are certainly counting on the drier and warmer summer. There are indications that the upcoming fall and winter may turn out to be colder and wetter. Some of this reasoning is based upon the changes of ocean temperatures in the south-central Pacific Ocean. It now appears that El Niño, the warmer-than-normal sea-surface temperature, is gone. The winter of 2009-’10 was greatly influenced by this phenomenon, warmer and drier than normal. Many of the Pacific storms went south into California.
At this moment, it looks like we’re in a La Nada, a cycle between El Niño and a cooler-than-normal La Niña pattern. However, ocean temperatures are cooling along the equatorial regions and we may be talking about a new La Niña within the next three to four months.