Tuesday, November 6, 2012
The Walla Walla Valley enjoyed one last mild weekend before the inevitable transition to something more seasonal: cold and white.
As a weak ridge of high pressure pushed the storm track north to the Canadian border and allowed a warm southwesterly flow to bathe our region, afternoon temperatures were a good 10-15 degrees above normal.
Those with an aversion to winter weather and the last few viticultural stragglers in our area were very grateful for the recent near-record maximum readings in the upper-60s and low 70s. The warmth permitted the former to enjoy their shorts and T-shirts for a couple of “bonus” days and the latter to let their late-ripening grapes hang a bit longer in hopes that something magical might occur in that time.
Unfortunately for them, as sure as darkness now descends upon our part of the world an hour earlier than it did last week, this aberrantly warm pattern will revert to a colder and perhaps snowier regime as the current week wears on. A series of cold fronts spun off from a cold trough of low pressure will migrate south along the British Columbia coast, which should bring progressively colder, wetter weather to southeastern Washington with each successive frontal passage.
After another rather cloudy but mild day today, the initial cold front will arrive Wednesday accompanied by a temperature drop of 10 degrees or more, though there will be very little, if any, rainfall as it progresses across our forecast area.
The trough should deepen during the latter part of the week. It appears by late Friday or early Saturday the snow level will lower to 1,000-1,500 feet locally and snow showers on the Valley floor will become a real possibility — though an accumulating snow is unlikely given the light and showery nature of the expected precipitation and the relatively warm ground upon which it will be falling.
This will set the stage for a change to a wetter overall pattern beginning Sunday and continuing into the following week, with the Global Forecast System model offering a possible (minor) snow event on Wednesday Nov. 14.
Your hobbling forecaster will be getting his right knee replaced that day and eagerly looks forward to negotiating the snow-covered, slippery sidewalks of November and December with crutches. The crutches, it is hoped, will not need to be retained for a winter-type injury incurred while waltzing through the Walla Walla white stuff.
Back east, where recovery from Sandy is proceeding slowly, storm-weary residents will have new and equally unpleasant weather issues of their own to confront this week: The weather gods seem determined to heap insult upon injury with a significant “nor’easter” forecast to move up the coastline on Wednesday and Thursday.
It is expected to bring with it another round of above-normal tides, beach erosion, heavy rain and lashing winds — though nothing approaching the brute force of the “superstorm” that visited death and destruction across the same area a week ago. Again, a phasing of jet stream energy moving in from the west with a low pressure system organizing in the Gulf of Mexico will be responsible for the rapid development of a deep low that “bombs out,” which in weather parlance means the pressure falls sharply to produce one to three inches of rain and winds gusting to 55 miles per hour in coastal areas of Maryland, Delaware, New Jersey and New York and heavy, wet snow to inland areas.
The sole bright spot in an otherwise dismal forecast is the differing models — one of which brings the core of the storm some 150 miles to the east of the track forecast by the other as it parallels the coast on its northeasterly path, which would mean a somewhat less intense event for the unlucky inhabitants there.
Mother Nature can on occasion be a very cruel mistress, indeed.
A lifelong fan of both the weather and the Baltimore Orioles, Jeff Popick is an instructor at the Enology and Viticulture Center at Walla Walla Community College and manages the school’s teaching vineyard. Send your questions and comments to him at firstname.lastname@example.org.