By George Haglund
For the Examiner
A quick slide into fall and winter started on Oct. 13. We knew it was coming, but most of us were surprised it took so long to arrive.
Starting July 24, Coupeville experienced drought conditions with only about 0.2 inches of rain – the same amount we received on the day the drought ended.
The weather on Oct. 20 really sealed the arrival of fall. A heavy rain shower in the morning delayed my trip to Coupeville to run some errands. The raindrops were really big, which my wife calls “fat rain.” As I later ventured toward Coupeville, I was surprised to see white roads and rooftops from a hail shower. The hail appeared to be heaviest around the Prairie Center area. The fat rain near Crockett Lake was the result of slightly warmer temperatures and melted hail.
The real excitement occurred at about 4 p.m., however, when many people reported seeing a waterspout between south Whidbey Island and Everett, near Hat Island. A waterspout is a tornado that occurs over water. In this case the waterspout dissipated before reaching land so did no damage.
For such a dramatic shift in the weather you would expect that a fundamental change had occurred. That change is directly related to the location of the upper-level jet stream. During our 80-day dry period the jet stream was far to the north, and during the rainy period of Oct. 13-19, the jet stream was directly overhead.
It’s now shifted further south to northern California, which allows a large mass of cold air to flow in our direction.
The cold air aloft makes for unstable conditions, which produces lots of cumulus clouds (the cotton-ball type), showers, hail, and possible lightning and thunder, and yes, even a waterspout. Fortunately, tornadoes and waterspouts are rare in Washington, with only one or two a year.
A look back at our summer is worthwhile as it was so pleasant and memorable. I spent some time checking the Coupeville monthly weather records recorded by the Engle family at the website of the National Climatic Data Center. The 80-day dry period turns out to be historic.
There is only the year 1942 that even comes close to matching this dry spell. The rainfall total in 1942 over the 80-day period from July 24 to October 11 was 0.38 inches with rain on eight days.
A normal amount of rain over that period would be 2.8 inches. This year I measured only 0.22 inches of rain on 5 days. The WSU AgWeather Coupeville data is similar with 0.19 inches of rain on six days. It is normal for us to have a dry spell during the summer, but 2012 proved to be a one-of-a-kind summer.
With the arrival of colder weather we should be thinking about winterizing our homes. The average date of first freeze in Coupeville is Oct. 30. By Nov. 11 the probability of first freeze is up to 80 percent.
A glance in the direction of the Olympic Mountains when they are visible shows new snow on the peaks and even on the foothills as low as 3,000 feet elevation.
Ready or not, here comes winter!