Expect early May to be wet, filled with storms

The Inland Northwest finally received some pleasant springlike weather last weekend. Despite temperatures in the 60s and low 70s, April’s average temperature is still several degrees below normal. The nice weather didn’t last long, as we’ve once again seen temperatures plunge to below-average levels with increasing rain and snow.

It’s still possible that we may see a few more snowflakes this weekend around the full moon cycle on Sunday. However, I expect to see temperatures rebound into the 60s and 70s during the last part of April and the first few days of May. The next warm period should last a bit longer than the one we had last weekend.

Although temperatures should be very pleasant in the coming weeks, the overall spring season should still remain a bit cooler and wetter than normal. The first three weeks of May should be the wettest period of the spring season and likewise cooler than normal. Don’t be surprised to see widespread thunderstorm activity across much of the region.

Since the beginning of 2008, global temperatures have dramatically cooled to near the 20th-century average. Scientists blame the recent drop to extremely low sunspot activity and the cooler than normal sea-surface temperature event, La Niña, in the south-central Pacific Ocean.

As La Niña dominated the ocean waters during the last winter season, record snows were observed in parts of the Inland Northwest as well as many northern regions of the U.S.

Prior to the early 1990s, it would usually take several years for sea-surface temperatures to oscillate from a La Niña to El Niño, the warmer than normal sea-surface temperature pattern. Since that time, we’ve seen ocean waters dramatically go from warm to cold, and vice versa, within months, rather than years.

Within the last several weeks, ocean temperatures began warming once again. There is still a large region of colder waters along the equatorial regions, but readings have been climbing along South America’s Pacific Coast. When sea-surface temperatures in this region start warming, it takes only a few months for scientists to declare a new El Niño event. Don’t be surprised to hear about this new El Niño by the late summer or early fall season.

It’s difficult to say at this point what effect a strong El Niño would have on the coming winter. We still have extremely low solar activity. But, I do think the winter of 2008-09 will be different than our recent 2007-08 season.

As local weather patterns continue to be, at least in part, influenced by La Niña, the upcoming summer season should be warm with occasional thunderstorms. Moisture totals in our region should be slightly higher than last year. It’s likely that we will see at least two or three afternoons during the July 18-25 full moon cycle with toasty readings near or above the century mark. Early August may likewise be briefly baked by triple-digit temperatures.