10/22/2014

Currently

55°F

Light Rain
Humidity: 94%
Pressure: 29.70 in

Weather

Potpourri blog: A waterspout (almost), strange radar blob, wind microclimates

Potpourri blog: A waterspout (almost), strange radar blob, wind microclimates
Show Caption

As Western Washington finally gets a chance to wring out after what was a record wet March 16 and may soon be a record-wet March in general (7.69" of rain so far this month; record is 8.40") there's a few interesting weather tidbits of late I wanted to highlight.

First, let's start with the thunderstorm that rolled through the Whidbey Island/Snohomish County areas on Friday. It brought some lightning and hail, but did you know it almost brought us a waterspout as well?

As the strong storm formed just to the west of Whidbey Island, radar did indicate some weak rotation was present in the clouds. Luckily Greg Johnson of has 2 HD cameras constantly recording his view to the north and the cell was going to drift right across center stage.

So we watched eagerly for any signs of rotation, but nothing obvious came about and the storm went on to dust Edmonds with some hail and then fizzled.

But Johnson went back over the video and found something that did show rotation and the inklings of a waterspout, and other local meteorologists agree it was likely an infant stage waterspout that never got going.

I've posted a still shot and then the video below. It's not the most obvious thing in the world, but notice the sea spray in the middle and the rotating clouds above it. The spray is likely the start of the funneling winds.



And here is the video:



As I said, not the most exciting thing ever but a reminder that tornadoes and waterspouts, while quite rare here, are not unheard of! And March and April are our prime times as we get frequent unstable air masses as the result of spring warmth starting to battle with lingering winter chills.

What Strong Winds?

Chris Hodgkin wrote me a puzzled email this morning wondering why the Port Townsend to Keystone ferries were canceled for much of Monday morning due to strong winds and heavy seas while it was nearly calm just up the waters a bit at his San Juan Islands home.

Further research revealed that winds at the Keystone Ferry Terminal were nearly calm through the morning, while similar calm conditions were reported in some part of the Port Townsend area, but not others, and one gauge out farther into the water on the Coupeville side reported consistent gusts of 30-45 mph through the morning.

We had some moderately strong winds pushing west down the Strait of Juan de Fuca in the wake of Sunday's storm and they get accelerated a bit when they try to squeeze through the narrow gap in terrain between Port Townsend and Whidbey Island.

Here is a map of where some of the wind gauges are so you can see this effect (using A,B,C and D instead of their actual codes like "E4723" for ease of keeping track):



And here is the link to the wind speeds that morning:

* Station A
* Station B
* Station C (Pt. Wilson)
* Station D

(Note Station B is on the south side of a little inlet providing some buffer for a NW wind.)

Station A was in the 10-15 mph range Monday morning, while Station B was in the 5-15 mph range yet Station C and Coupeville were 30-45 mph, Station D was around 20, and the Keystone Terminal was nearly calm. All within roughly 8 miles of each other! Another example of our area's crazy topography and microclimates.

Why does radar always show it's raining off Hoquiam?

Had a few question on this one. If you look at the radar image this morning, you'll see a strange return near Hoquiam that never seems to move:



That occurs when we have heavy surf off the coast near Westport -- the waves are sending radar signals back to the nearby radar at Langley Hill and tricking it into thinking it's raining there.

Share:
Gust front's 0-to-60 mph time rivals turbo-charged V8s Gust front's 0-to-60 mph time rivals turbo-charged V8s