The warm-weather honeymoon is over
Up to now, the coldest temperature reported at the Spokane Airport has been 20 degrees, with no measurable snow during the first 12 days of this month (Coeur d’Alene had less than 1 inch).
The honeymoon is over, though, and hopefully you’ve got plenty of firewood on hand and a good working snow thrower (or at least a strong arm and a sturdy shovel). The computer models have put us in the path of an Arctic blast that even the Rocky Mountains cannot shield us from. But before the cold air even arrives, snow, blowing snow and potentially lots of both are possible for many areas of the Inland Northwest including the valley locations this weekend.
Earlier in the week, a winter storm watch was issued for much of Eastern Washington and North Idaho. In contrast to a winter storm warning, a watch is usually issued 1 to 3 days ahead of a potentially big storm. The key word in this type of bulletin is potential, not certainty. It is issued to give people a heads-up so they won’t be caught unprepared in the event the big storm does materialize.
Like severe thunderstorm or tornado watches in the Midwest, there are times when the set-up looks potentially good for a large-scale weather event, but in the end a key ingredient comes up short and we are left with a “bust,” or a big storm which turns out to be a no-show. That is why when you hear the words “watch” in any type of weather bulletin, it is time to be on the alert, but not batten down the hatches just yet.
A warning on the other hand, is a type of weather bulletin issued when a particular weather event is imminent. Winter storm warnings are issued when any of the following types of weather are expected: at least 4 inches of snow in 12 hours for valley locations, or 8 inches in 12 hours for mountains (mountains are considered to be elevations above 3000 feet), a half-inch of sleet or more, reduced visibilities of quarter-mile or less due to blowing snow, or any combination of these events.
Two weather events that have their own special warning include the ice-storm warning, issued when quarter-inch or more of ice is expected, and the blizzard warning, issued when visibilities are reduced to less than a quarter-mile due to blowing snow along with sustained winds or frequent gusts of 35 mph or more. Winter weather advisories can also be issued, which indicate a less severe occurrence of some of these weather hazards.
My ears have already perked up to the chatter of how local storms can be over sensationalized by the media. In fairness, it is our duty to communicate and explain to you, important weather bulletins that are issued by your taxpayer funded local Weather Service Office. The amount of song and dance we add to such information varies greatly from one weather personality to the next, and you get to choose who you want to watch. Such is the nature of the business.