TBF Preparations (2) - Wind and Weather

“Our most variable season is winter – not the calendar winter, but the months from November through February“

Kimball Livingston, Sailing the Bay, 1st edition

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(B)log . . .

None for this post, I’m setting aside the journal entries to focus on the TBF Preparations
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My Blog . . .

My preparation for the Three Bridge Fiasco (TBF) continues.

To understand the TBF, check out EVK4's post on the subject.

I went to bed (Jan. 12th) with the howl of the Northeast wind threatening to dislodge my son’s Dish Network hardware from the corner of the roof just above my head. I went to sleep dreaming that it took the corner of the roof off, just like those Midwest videos of Tornados ripping houses apart. I’ll welcome the next earthquake, as long as I wake up to a house with a roof over my head. Even if the books that were on my shelves are now on my floor.

This morning I awoke with a roof over my head. The KTVU newscast came on when I turned the TV on, so I guess the dish is still on the roof, pointed in the same direction.

I like KTVU. The station is next to the water, so the roof top cameras show the weather on the bay. Nice. Very nice since it’s January and the temps are forecast to be in the 70’s (who can go sailing with me?).

And, it’s going to stay that way for the rest of the week.

So I updated the links on my BLOG homepage to get my readers to the surface analysis website and also to the SJSU Real Time Streaklines Animation.

As I drove to work, I paid special attention to the direction the flags were flying, and the trees were bending.

High pressure areas have clockwise airflows, they counter rotate relative to storm systems, which rotate around low pressure areas.

Today we have an oblong double high over the far Northern California and Nevada areas. KTVU says the weather will be dominated by the high pressure systems for at least the next 10 days.



This is winter in Northern California, in the shadow of the weather systems, highs and lows, that pass to the north, or right overhead. Or sometimes roar down from the gulf of Alaska, following the coastline until they surprise Hollywood with some natural drama.

But today as I write this (Jan 13th), there is a tight grouping of isobar lines on the southwest side of this oblong. Draw an arrow perpendicular to these lines, and it points straight at San Francisco Bay. Mother Nature has her own way of playing Cupid. That arrow delivers warm weather – and lots of warm wind.

I guess it’s her way of playing nice after a month of seasonal temperatures.

There is a low pressure trough hugging the coast line, creating a trench for the warm, high pressure air to slip over the edge of that trench and try to fill the relative vacuum of the low pressure.

This trough is shown on the charts as a dotted line.

That is the story that the surface analysis tells; the explanation for God’s distaste for the Dish.

Further out, there is a low pressure system shown as a tight grouping of concentric isobars. Between that and us is a grouping of smaller low pressure systems backed up between 135W and 165W, with two of them tucked into the Gulf of Alaska.

It’s now Jan. 20th. We’ve been blessed by warm weather and though the winds have been light, there have been some spectacular (for winter!) sailing days. Charlie Bergstedt’s Blog is a fantastic record of this weather as the low pressure systems have sorted themselves out, but haven’t pushed the High pressure Eastward . . . yet.

His pictures of yesterday's sunset tell the tale - an approaching line of clouds makes for a brilliant sunset, and signals the approach of a cold front.

The surface analysis now shows a series of weather systems lined up like impatient crowds at an inauguration on a cold day in DC, waiting for the speeches to begin, then waiting for them to end, then waiting for the trains to get them out of there.

The TBF is now about 11 days away. Today’s Intellicast Mixed Surface Analysis image shows the approaching cloud cover pushed up against the trough that hugs the coast line. There is an informational page associated with it that explains what the symbols mean. There is a series of large cold fronts with very short warm fronts associated with each of these weather systems stacked up across the Pacific.

What I’m looking and hoping for is an Occluded Cyclone to develop – a warm front ahead of a cold front, poised off of the bay area the day of the TBF. Should that happen, we can expect a warm South Wind to prevail, creating a long spinnaker run from Yerba Buena Island to Red Rock.

Hope springs eternal.

As each of the low pressure systems approach, I’ll start keeping track of whether they form such a system, how long they take to get here, and how wide they are. This will help estimate just what sort of weather we’ll have 11 days from now.

I’ll pay particular attention to the streakline images associated with the different phases of the approaching low pressure systems.

They talk about a ‘storm door’ opening to let these systems flow on shore.

We’ll see.