Wednesday, March 2, 2011

NW Hurricane and the Secrets of Solander

The big storm moved up the Northwest coast today and it did not disappoint, winds gusted to 116 mph at Mt. Baker and to 90 knots (104 mph) at Solander Island. Here over the lowlands, lots of places over Puget Sound gusted to 40-50 mph, over Northwest Washington to 50-70 mph, and even stronger wind hit the coast, particularly the coasts of Vancouver Is. and Oregon. Cape Arago on the central Oregon coast reached 64 knots (75 mph). There were scattered power outages throughout the region and I had to carry my bicycle across a huge fallen tree to get home!

A beautiful storm from space....here are the infrared and visible images at 10 AM this morning. At this point the storm was moving past the northwest tip of Vancouver Is.. The central pressure at this time was roughly 965 mb--the forecast was really quite excellent.

Just a reminder--the visible image shows what you would see if you were looking down from space. The infrared (IR) image tells you the temperature of the clouds and surface--with cool temperatures shown by white and warmer temps by dark shades, with grey in between. Since temperature generally declines with height this tells you a lot about the height of clouds.


The strongest winds near sea level was at Solander Island, located off the northwest section of Vancouver Isl. (see map)

Here is a picture of the barren islet, a place with no trees.

Take a look at the winds there:
The sustained winds (SP) reached 72 knots and the highest wind over the hour, the peak wind (PK) reached at amazing 90 knots (104 mph).

Now let me be honest with you. Solander has its issues...and is known for reporting crazy high winds--higher the nearby locations. Many of us suspect that terrain-induced acceleration gives the winds a boost there. First, the anemometer is on top of the terrain...and flow would be accelerated as it moved up the windward cliffs. Second, the island is just offshore of a protruding headland of fairly high terrain--which may accelerate the winds in the region (like the strong winds around the edges of big building!) The following two terrain maps illustrated that headland.
The red "A" shows where the island is.

No comments:

Post a Comment