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Thread: Feb 22: Wave alert (Off shore wind event)

  1. #1
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    Feb 22: Wave alert (Off shore wind event)

    Off shore wind setup (#3 for the season) looks to be in the pipe for this Sunday, Feb 22.
    Click image for larger version. 

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    Compared to:
    - Dec 30, too strong winds, 50 knots at 11,000 ft (90 knots at 18K !!)
    https://www.williamssoaring.com/news/...-30-wave-watch
    - Jan 24, too weak of winds, 20 knots or less at 11,000 ft.
    https://www.williamssoaring.com/news/...ind-wave-setup

    this looks to be much more reasonable. "Reasonable" is:
    - 20-25 knots @ 850mb
    - 30-35 knots @ 700mb
    - 50-60 knots @ 500 mb
    and this is about what this Sunday looks like. Too strong of wind suppresses the "bounce" of the air, while too weak doesn't get enough energy to "bounce".

    The Windyty view for 5,000 ft & 9a Sunday is:
    Click image for larger version. 

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    The direction is also very good, lower levels at 060, then at 500mb, going northerly at 010. This direction shift above 11,000 ft. will suppress the bounce to some degree at higher altitudes. The timing looks good as the best part of the setup is late afternoon Sunday. As with the above dates, this setup was in & out of forecast since almost 16 days ago due to the cutoff low.

    Now that we're inside of 5 days, I'm focused on an attempt. Tom Bjork & I will give this a go in his '30. The winds look to work best down south to at most, the Santa Cruz range. So at the moment, my bias is to keep the task north of the Bay Area: Goat > San Hedrin > S of Eureka > Mayacamas Ridge > Mt. Tam > Santa Cruz range > and back track to WSC.
    Click image for larger version. 

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    Will post more as we get closer.
    Last edited by Kempton; 02-19-2015 at 03:08 PM.
    Kemp
    ASH-25 (FNX)

  2. #2
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    Re: Feb 22: Wave alert (Off shore wind event)

    Update Wed afternoon. For Sunday, the center of the cutoff low moved about 200 miles north. This dropped wind speeds over the northern coast range to sub-wave speed. Since this cutoff low is a wandering entity, it may move back to a favorable setup but for right now, it's not forecast to do what was stated in the above post. The cutoff low is being "bullied about" so to speak.....
    Kemp
    ASH-25 (FNX)

  3. #3
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    Re: Feb 22: Wave alert (Off shore wind event)

    Hi Kempton,

    i have no '30 available ;-) but just got my US licence from the FAA - if there is an opportunity to get some 'flyable' object for me, i'll clearly will give it a try !

    -- Martin

  4. #4
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    Re: Feb 22: Wave alert (Off shore wind event)

    Martin,
    Good to hear! Now to get you up to WSC more often and fly...
    Kemp
    ASH-25 (FNX)

  5. #5
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    Re: Feb 22: Wave alert (Off shore wind event)

    Feb 19 update, 3 days out. Forecast is back on, similar to 5 days ago. This greater "wobble" in the forecast so close to the target day is something I'm still getting use to. Still favoring the Mendocino's only, with little to no effect except in extreme Southern California:
    Click image for larger version. 

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    I compare Sunday & Monday to Nov 22, 2013 as that is the only off shore setup that I actually flew to prove out the forecast. The big difference btwn then and now is the greater instability as the Mendos are so close to the low pressure center for this Sun/Mon. We'll see what the RASP forecasts show come this evening.
    Kemp
    ASH-25 (FNX)

  6. #6
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    Re: Feb 22: Wave alert (Off shore wind event)

    Great! How does it look for Saturday?

    Ramy

  7. #7
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    Re: Feb 22: Wave alert (Off shore wind event)

    NW wind, the RASP for WSC shows a Saturday morning wave, then dissipates over the day.

    Just to be clear, the forecast is very unstable as we've already seen because:
    - The cutoff low is a very small feature, so is easily pushed around compared to the 2,000 miles diameter lows & highs
    - Further, since the center of the low is right over central California, a 100 mile movement in any direction really affects the wind direction forecast at any point in our soaring arena.


    In addition, since this is a low pressure system, the depth of the unstable layer is greater the closer the center is to our soaring area, so the risk that wave action may not happen is greater.

    Lots of differences from an "ordinary" wave day, so we will see....
    Last edited by Kempton; 02-19-2015 at 02:33 PM.
    Kemp
    ASH-25 (FNX)

  8. #8
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    Re: Feb 22: Wave alert (Off shore wind event)

    Yeah, windyty shows how small changes in time a and location will make huge difference. Wind direction changes almost 180 degrees within 200 miles!

    Ramy

  9. #9
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    Re: Feb 22: Wave alert (Off shore wind event)

    IF the forecast manifests as reality, then I'm thinking the task is more like:
    Click image for larger version. 

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    Kemp
    ASH-25 (FNX)

  10. #10
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    Re: Feb 22: Wave alert (Off shore wind event)

    Now you got me excited! Looks like if not wave we may get nice cu's over the Mendos and towards the coast, maybe mix of wave and thermals? I recall Sergio flew with Alby to the coast and back on a similar day few years ago.

    Ramy

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