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  1. #1
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    Where Does the Wind (forecast) Come From ?

    And don't tell me it originates from the shredmachine's or the gnome's hindquarters...

    So, before the forum blows up again with the re-appearance of the njshredmachine as the barrel-buoy and before the advent of the multiplying gnome-clones...

    Serious query: the wind is oft-times more critical to surfable waves than any other factor. Yet, the wind predictions on the various sites are even more disparate than the swell forecasts.

    Example:
    at the moment, windguru.com has Sunday's AI wind as nominal at WNW under 3 to 4;
    yet, SI has Sunday's AI wind pegged at 10 kots from the NE.

    The former wouldn't make a difference on 'surfability' while the latter would make it chop city. And it's not unusual to see the wind predicto-meters on these sites stay at variance with each other.

    Question: where do the various sites garner their wind info? Because I'm figuring that whereas swell is forecast from people like SI and Surline whose predictors have oceanography degrees, buoy data & all the scientific stuff that I have no clue about, yet wind must be calculated from NOAA or another 'official' site.
    (What do I know? Very little, that's correct. That's why I'm asking.)

    Gracias!
    Last edited by yankee; Jul 10, 2013 at 09:08 PM.

  2. #2
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    "It don't take a weatherman to know which way the wind blows." You're making my brain hurt. "There is what we know, what we don't know, and what we don't know we don't know." Go figure. Any other questions?

  3. #3
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    Quote Originally Posted by sisurfdogg View Post
    "It don't take a weatherman to know which way the wind blows." You're making my brain hurt. "There is what we know, what we don't know, and what we don't know we don't know." Go figure. Any other questions?
    Awesome! Appreciate the insights. Sorry I disturbed you, go back to your comic book.

  4. #4
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    I've seen the disparities and often wondered the same..who is the "official" authority on wind, and where do the disparities originate?

    *sisurfdog, you seem to get headaches frequently, maybe you should get the ole' noggin checked out.
    Last edited by seldom seen; Jul 10, 2013 at 09:45 PM.

  5. #5
    This may not be what you were looking for but heres my best shot... Winds are caused by pressure differences in the atmosphere (Pressure gradient) The way winds blows is associated with a front. Low fronts associate with stormy weather while High fronts usually bring clear skies. About how sites predict the surf forecast and winds is all based on models and computers, this changes daily due to storms and the unpredictability of the fronts. Usually sites (SI,MSW,Surfline) can have an in the ball park estimate of a swell about a week in advance but like i said the weather is so unpredictable it can change instantly, but as the desired date gets closer the report becomes more accurate because the front is more solidified and the computer scans basically have the data spot on. Waves are usually best after storms because of the prevailing west winds as the low front moves out and the high pushes in as well as the windswell produced at sea by the storm or ground swell
    Last edited by john219921; Jul 10, 2013 at 09:43 PM.

  6. #6
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    Quote Originally Posted by john219921 View Post
    This post was actually very hard to understand but here is my answer, it may not be what you were looking for but heres my best shot... Winds are caused by pressure differences in the atmosphere (Pressure gradient) The way winds blows is associated with a front. Low fronts associate with stormy weather while High fronts usually bring clear skies. About how sites predict the surf forecast and winds is all based on models and computers, this changes daily due to storms and the unpredictability of the fronts. Usually sites (SI,MSW,Surfline) can have an in the ball park estimate of a swell about a week in advance but like i said the weather is so unpredictable it can change instantly, but as the desired date gets closer the report becomes more accurate because the front is more solidified and the computer scans basically have the data spot on. Waves are usually best after storms because of the prevailing west winds as the low front moves out and the high pushes in as well as the windswell produced at sea by the storm or ground swell
    I appreciate the explanation, man; thank you.

    Follow up question - - so, are the wave-forecasting site-gurus utilizing different wind predicto services?

    Because the surf sites are not even in the same realm on many days in re: wind predictions. Whereas they are usually pretty similar with their swell predictions.

  7. #7
    Disparities in temperature between air masses as well as air pressure predict winds. Cool air is heavier than warm air so when a mass of cool air converges with a mass of warm air the masses slide across one another creating wind (This is the same way ocean currents occur, but then we are getting into convection cells which also occur in wind). Obviously, air flows from areas of high pressure to low pressure, also contributing to wind. In reality though, there are too many factors and we yet lack the technology to predict wind with any real degree of certainty.

  8. #8
    Quote Originally Posted by Bill Cosby's nephew View Post
    Disparities in temperature between air masses as well as air pressure predict winds. Cool air is heavier than warm air so when a mass of cool air converges with a mass of warm air the masses slide across one another creating wind (This is the same way ocean currents occur, but then we are getting into convection cells which also occur in wind). Obviously, air flows from areas of high pressure to low pressure, also contributing to wind. In reality though, there are too many factors and we yet lack the technology to predict wind with any real degree of certainty.
    Thanks Dikipedia!

  9. #9
    i wish i could answer that question because i am usually scrambiling to find out my local spots forecast and i see 3 different forecasts each with a different wind prediction.. My guess is they either bull**** it (unlikely) use their own instruments (may not be up to date) or NOAA or someother top of the line predicting instruments which are the closest thing we have so far.

  10. #10
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    Quote Originally Posted by EmassSpicoli View Post
    Thanks Dikipedia!
    Ok, that was pretty funny. No offense to the Cos, it was pretty funny.