Friday, March 12, 2010
Wind and Snow
Its Friday morning and the front has just gone by. That is evident from the end of the moderate showers (see the radar image above) and the wind shift and pressure rise at Destruction Is on the Washington coast (see table).
Beautiful image of the front and the associated offshore low in the latest infrared satellite image (see below).The wind is about to pick up substantially as the low pressure center offshore moves across Vancouver Island into southern BC (see forecast surface wind chart for 10 PM tonight below). This configuration produces a large north-south pressure difference over our region and thus accelerates the winds. Winds will gust to 20-30 mph in the central sound and perhaps 40-50 mph over NW Washington (Strait of Georgia, northern Whidbey Island, San Juans). In fact, the winds are already starting to crank up there (Whidbey Island Naval Air Station gusting to 35 knots, 36 knots at Paine Field). Over the sound the winds are also strong (41 knots last hour at Alki). And strong winds along the coast.
But wind today and tonight is only half the major weather story. The other is snow.
During the past day there has been a major snow dump in the mountains (see pictures on I90 yesterday). Many locations have gotten a foot of snow and snow showers are continuing today (perhaps another 1/2 ft). This would be an excellent weekend for some skiing....but one major warning. There is a substantial avalanche threat with so much snow falling so quickly on a rather icy, hard-pack underlying foundation. If you are going into the mountains, and particularly if you are straying from controlled areas, check the Northwest Avalanche Center's excellent website
All this rain and snow is a very good thing. Lets face it, the Northwest's key resource is water...for energy, agriculture, fisheries, timber, and consumption. Its why it is better here than California. The large influx of moisture this week will have a significant positive impact on the snowpack and reservoir levels.
Posted by Cliff Mass at 10:10 AM