Video: Eddys, Fog and Micrometeorological River Spirits

[andyatos]

A couple of days before Sunday, October 1st I saw a sailing window that might be doable before the strong northwest coastal winds were going to come back. These short windows can appear when a counterclockwise spinning eddy forms along several hundred miles of the coast. This produces southeasterly flow along the coast and keeps the strong northwest winds farther offshore.

But the eddy effect can make it a chore to sail the 1st mile upstream on the Russian River. When there’s fog the southeast winds can be light and give you 360 degree variations in direction, especially early in the morning. But once you get upstream to the bridge, the southeast flow splits and half of it becomes westerly and flows up the Russian River in the usual sea breeze pattern.

The micrometeorological spirits that live along the river have powerful juju and they must have seen the big effort I was putting in to get to the bridge. Because once I finally got past the bridge, they gave me an incredible day with some truly amazing experiences. Here’s the video.

- Andy

 

[tag]

Great video, Andy.
Wow that really started out as a drifter, huh? That initial bit you couldn't even see ripples on the water.
What's the blue line you have up to the tack of the sail? Just to help pull the sail out?

 

[andyatos]

Wow that really started out as a drifter, huh? That initial bit you couldn't even see ripples on the water.

Yes sir. The only ripples were from my "bow wave". Go back to 25 seconds into the video and look at the bottom right hand corner. I'm moving right along.

 

[andyatos]

What's the blue line you have up to the tack of the sail? Just to help pull the sail out?

Exactly. It's the tail end of my halyard. Initially I did this to keep my mainsheet out of the water when I'm running in really light stuff. Especially now that I've gone to 2 to 1 on my mainsheet.



Yesterday I sailed for about 6 hours with two lines, one attached to each side of the tack. Spent a lot of time using them to sheet out the sail in zephyr situations. Here's footage of a short sheet out. The sound you hear is my mainsheet block.

Cheers,

- Andy

 

[tag]

Ok I see, very interesting. I use my bungee daggerboard retaining line to go to the tack of the sail.

 

[norcalsail]

A couple of days before Sunday, October 1st I saw a sailing window that might be doable before the strong northwest coastal winds were going to come back. These short windows can appear when a counterclockwise spinning eddy forms along several hundred miles of the coast. This produces southeasterly flow along the coast and keeps the strong northwest winds farther offshore.

But the eddy effect can make it a chore to sail the 1st mile upstream on the Russian River. When there’s fog the southeast winds can be light and give you 360 degree variations in direction, especially early in the morning. But once you get upstream to the bridge, the southeast flow splits and half of it becomes westerly and flows up the Russian River in the usual sea breeze pattern.

The micrometeorological spirits that live along the river have powerful juju and they must have seen the big effort I was putting in to get to the bridge. Because once I finally got past the bridge, they gave me an incredible day with some truly amazing experiences. Here’s the video.

- Andy

Great video Andy. Nice day on the Russian River! Looks like you were pointing pretty well in that section coming back from the Duncan's Mill bridge. Was it less tacking than last time we went? It looked like an easier run home than my previous times. I also like the hill there at minute 2:39. You got that on an earlier video too. Thanks for sharing...

 

[andyatos]

Looks like you were pointing pretty well in that section coming back from the Duncan's Mill bridge. Was it less tacking than last time we went? It looked like an easier run home than my previous times.

That's very observant of you.

Yes, there was a nice, slow, swinging back and forth of left and right shifts that I was able to tack on. Then I noticed that the wind was more right than usual heading up the Straightaway. And as I started upwind along the backside of the Willow Creek ridge, it was one, long, sustained righty that kept going more right the further downstream I went. Because of this, I only had to make one tack on to port (the video segment that starts at 7:03 minutes). The rest was starboard tack all the way up to the Cedar Trees where the flow, as usual, finally turns southwest as you approach The Venturi.

There's only been one other time that I've experienced a sustained righty like this while returning upwind along The Backside in all the years I've been sailing there. And it wasn't nearly as good as this recent one. For those who are curious about how this works, see the Google Earth screen shot below with my additions as to what I believe is happening.

The normal, accelerated flow comes squirting through The Venturi out of the southwest. When the air moving through that area is extra cold and right at the edge of the dew point it starts to flow up the southwest flanks of Cow Mountain. But it doesn't want to be lifted at all. It's a cold, inverted blob. So it sloshes up the side of Cow Mountain then washes back down towards the river as north to northeast flow, creating a sustained right shift that you can see cats pawing out on to the water.

The view was almost the same both times I have experienced this "mega righty; evaporating fog in The Venturi area and a cone of re-condensing fog on the side of Cow Mountain. This time was certainly my fastest transition along The Backside ever, a place that is usually a tack festival. Good stuff!

- Andy