Updated Blog: The North Pacific High returns but...

windfind · Joined: 18 Mar 1997 Posts: 1901

Hi Gang,

Check the update to this blog at the bottom of this forum post.

The Bay Area and Southern California are in for fairly mild winds this weekend. Why? Because the old NPH, which is currently only a sliver of NW wind off the Bay Area, fades away off Southern California.

Meanwhile the entire pacific between California and Hawaii is a mess of tiny counter-clockwise spinning storm systems as you can see in the image below.

However the video in this blog

http://blog.weatherflow.com/the-north-pacific-high-weakens-and-dies-then/

suggests that over the weekend a new massive NPH is created north of Hawaii and begins to march towards the California coast. If things go right the North Pacific High's surface NW winds should ramp up in Southern California and the Bay Area this coming Monday.

Mike Godsey
iwindsurf.com/ikitesurf.com
Weatheflow.com

MalibuGuru · Joined: 11 Nov 1993 Posts: 9300

Both your forecast and the nws forecast for Leo was very bad for today, but it was very nice this evening. Why?

windfind · Joined: 18 Mar 1997 Posts: 1901

Hi MalibuGuru,

I have gotten pretty good at predicting when a Catalina Eddy will spin up however none of the models nor my hundreds of hours studying the eddy have given me much insight into what time the eddy will die in a given morning.

If the eddy dies early in the morning there is a good chance the pressure gradient will cause the North Pacific High's surface NW winds to curve into Leo if they are strong enough.

But if the eddy lingers then the odds of good wind go down with each passing the hour the eddy endures since it routes the NW wind away from the coast.

So yesterday I thought the eddy would die very late meaning mild wind for Leo. But in fact the eddy faded fairly fast.

Dealing with the Catalina Eddy is especially difficult when forecasting for Leo since commonly there are weak offshore winds in the morning that keep the eddy away from the shore in that locale. So I can not see the actual eddy winds at Leo. So I also have to try to figure out what time in the morning those NE winds will die.

Very very slowly my skill at doing all of this goes up. And equally slowly the models improve. But there is still room for tons of improvement. Give me another 50 years I will have decent forecasts more often.

Mike Godsey
iwindsurf.com/ikitesurf.com
Weatheflow.com

MalibuGuru · Joined: 11 Nov 1993 Posts: 9300

Haha, thanks for the insight. Is there a way to instantaneously be alerted upon the eddy's demise to give us an extra hour to get there? I'm not very technical and just look out the window. I suppose I just answered my own question..

nw30 · Posted: Sat Apr 02, 2016 2:17 pm Post subject:

It was pretty good while it lasted, last night was scary good at A.L. with close to mast high sets (but a bit inconsistent, which is actually good) out of the south, with light but sailable wind, 5.7 a bit overpowered for me on the outside, perfect on the inside.
Nothing like big swells w/ light winds to get the heart pounding. Shocked

MalibuGuru · Joined: 11 Nov 1993 Posts: 9300

Logo high sets fown here last 2 days. Slog and catch.

Today is very iffy. Cabrillo is already ripping, but we are hazy light winds here. Probably will get to slog velocity today.

windfind · Joined: 18 Mar 1997 Posts: 1901

Hi Gang,

Here is an update to the blog teaser above.

It still looks like the North Pacific High slams against the coast Monday. And is still looks like the NW winds will stay focused mostly at Bay Area sites near the coast.

Take a look at the animation below.

1. Note the position of the North Pacific High. This time of year it should be W to WSW of the Bay Area. But it is actually in a position typical of mid June when its average location moves towards the Pacific Northwest. Can you see how its location Monday favors the Gorge? How does this impact the Bay Area wind?

2. Note that the biggest low pressure is in the northern Great Basin where you see much of the wind going. Note all the wind being diverted into that area rather than over the Bay Area. Typically this time of the year the low pressure is more in the southern Great Basin. How does this impact the Bay Area wind?

3. Now note the low pressure in the Central Valley is focused towards Bakersfield rather than in the Sacramento area. How does that impact the Bay Area wind Monday?

4. Note the wind being diverted from the North Pacific High into the Gorge. This time of year the Columbia Basin is relatively cool. So why would you forecast gusty Gorge winds Monday?

See the blog link tomorrow for the answers.

If anyone would like to take a stab at answering these questions I will give anyone with the right answers a custom San Carlos Baja forecast.

Mike Godsey
iwindsurf.com/ikitesurf.com
Weatheflow.com

MalibuGuru · Joined: 11 Nov 1993 Posts: 9300

17 mph again today at 1pm. That makes 4 days in a row for wind here.

nw30 · Posted: Sun Apr 03, 2016 4:44 pm Post subject:

I live right between the letters 'V' and 'a' in the word Valley, it might be time for another happy dance.