The Coming of the Wind – and Spring
Perhaps it was bothering you, too. For several weeks leading up to the last few days of March there was no wind. I would wander through my garden and yard, wondering in the back of my mind where the wind was. Much as I get cranky about those strong gusty winds, I was left with some odd sense that, without the wind, we could not have spring.
Then it blew in. By the end of March it had again inserted itself into our psyches. Last Saturday evening, wind was on the lips of several homeys.
During that Chukar Run Banquet evening, we were celebrating the 96th birthday of the Kittitas County Field and Stream Club. [It was a great evening, thank you. We raised a fair pot of funds for Fifth Grade Camp, our Washington Children’s Outdoor Bill of Rights initiative and the club’s work on behalf of maintaining access to the public lands of Paradise.] Now that I think about it, some of those “windy” comments may have been directed at our MC. Hmmm. Be that as it may, a couple of the questions got me thinking about my responsibilities as resident meteorologist of the Reecer Creek Rod, Gun, Working Dog & Outdoor Think Tank Benevolent Association and Chair of the Human Response to Weather Subcommittee.
As we were admiring a wind vane in the line of silent auction items, one of my favorite outdoor nuts leaned over and quietly asked, “Okay, so spring is here. What is this stuff with the wind? You’re supposed to know about this. What is it about walking around a corner into a warm blast of wind and suddenly getting so cranky I just want to pop someone? And clouds…?” He nodded toward his wife, laughing with a friend. “She freaked out with those cloud days a few weeks ago…” I suggested a cool malt beverage, promised to talk more about it, and got back to my MC duties. Clearly there is work to be done. In the next week or two, we will explore the effects of wind and weather on humans, but for now let’s think about those winds.
Air is just a light fluid. Like water and other fluids, it seeks “leveling.” Lift a bucket of water from a tub, and the other water flows to the fill in the hole. Air is the same way.
Warm air may be light enough to create a “low pressure” area. More dense air (from a “high pressure”) may then flow to fill it. Air moves always from high to low pressure, down what is called a “pressure gradient.”
We have three general types of winds in Paradise: cyclonic, mountain‑valley and katabatic.
The vast majority of our winds, however, are simple pressure gradient winds. They blow in from the northwest, coinciding with our valley’s unique topographic northwest-southeast alignment. Our Strongest winds will be associated with a high pressure over the cool water off our northwest coast and a low pressure from warming out in the Columbia Basin (or even southern Idaho) creating a steep pressure gradient. You already know that we now begin our windy season.
Cyclonic winds come with large storm systems moving across the region. The big winds on the coast this winter were cyclonic winds, moving around, and into, the lows at the center of the storms.
Mountain-valley winds move up and down the canyons around Paradise, as a result of differential heating and cooling. Warming atop a hill may draw air up (morning valley breeze); cooling or snow up high may increase the density of air until it slides down (evening mountain breeze) into the valley.
Katabatic winds blow downhill. Our most common katabatic wind is the Chinook (though we see less of it than White Swan or Wenatchee). Air moving up the west side of the Cascades may push up against a “lid” of stable air over the crest and be forced down the east side and/or drawn into a sunny and warm area of low pressure off to the southeast. It will be heated by compression as it flows downhill into Paradise, becoming relatively drier and drier (thus our “rainshadow”).
Winds here are strongest during the warm season and in afternoon/evening – thermally driven. There certainly are calm periods through the year, although along the higher ridges around us the winds are relatively dependable. As the air rises up onto and over those ridges, it is compressed to varying degrees against the stable upper atmosphere; that compressed (more dense) air will move a turbine blade more easily than less dense air at a given speed. Thus are fueled the wind turbines around our valley.
For current winds at Bowers Field, and a look at the latest three days, check out weather.noaa.gov/weather/current/KELN.html. For wind and temperature patterns along a very cool interactive I-90 profile between Seattle and Ellensburg, go play at i90.atmos.washington.edu/roadview/i90.
Whatever you do, celebrate these glorious, if occasionally cursed, winds sent to awaken us to spring. Say a little prayer for those poor devils who must live in calm, dead places and breathe the same air over and over and over.
