By Bill Biddle
September 2009 is just about in the annals of time as you read this October Weatherwatch. And what a month September was! The Wolf Creek weather station reported a high of 100 degrees and a low of 32 degrees with a precipitation of .63 inches. This is a late summer classic temperature range and precipitation for a continental climate based on the much revered “Climates of the World,” which was the standard text for geography courses at universities from 1940 to 1960. Inner Mongolia, for instance, is in the same climatic regime as the Methow valley. The high steppes of the world are truly continental with hot summers, cold winters, and 10 to 20 inches annually of precipitation. (Snowfall is calculated by water content, so 60 inches of snow in the Methow is six inches of rain, or precipitation.)
September ended with a cool-down after almost a week of 80-degree temperatures, but this return to the normal highs of 60 degrees for early autumn will proceed apace as October is upon us. It is very important to remember that late October has had in the past some significant snowfalls. Some of these snowstorms come even before Halloween. More on the October forecast in a paragraph or two – read on, dear reader.
Classic equinoctial storms occurred in various parts of the world around the autumnal equinox on Sept. 22. The southeastern United States was inundated by a slow-moving low-pressure area that delivered upwards of 10 inches of rain to some places. On the other side of the world, Sidney, Australia, had the worst dust storm in its history. Heavy rain one place, blinding dust another place. The world will see more extreme weather events in the future.
The future of polar ice is in the process of altering to the point that its decrease will affect in a dramatic way the climates of the world, including our Methow continental climate. The Seattle Times of Sept. 24 (the one with the article on Winthrop which labels it as one of five towns in Washington “that are tops for outdoor life”) has an article on polar ice melt. It is a long article that should be read by Weatherwatch readers. In summary, it states that the polar ice in Antarctica and Greenland is melting far faster than scientists had thought. A UC-Berkeley climate expert calls this “ominous and distressing.” Weatherwatch will discuss this in a future column.
October will start with a week of sun and showery clouds, with early-autumn chill. Wet snow will coat Washington and Rainy passes on the North Cascades Highway. Rain in the middle of the month will be heavy at times and snow at the end of the month will usher in winter. Yes, you read that correctly – snow. Be prepared!
Percy Bysshe Shelley gives a poetic look at the clouds that will bring this rain and snow to the valley. In his poem “The Cloud” of 1820 he writes:
I am the daughter of Earth and Water,
And the nursling of the Sky;
I pass through the pores of the ocean and shores;
I change, but I cannot die.
November and more clouds and more snow? Stay tuned!