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This topic contains 61 replies, has 5 voices, and was last updated by  Bronco Bill 5 years, 9 months ago.

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    Some pilots want to be automatically notified when a weather forecast is made, so they know ASAP what others think of our chance for soaring.

    But this forum typical is “pull” technology, meaning that one has to visit a page to get info, contrary to “push” systems where a user is automatically emailed that a new reply is made.

    One way around this, is to keep a single topic (this one) to discuss current weather forecasting, and people can either click the “Subscribe” link at the top right, or make a post in this topic and choosing the ” Notify me of follow-up replies via email ” checkbox at the bottom. They will then get notified of new postings within this discussion. It should be easy to stop notifications later if they choose.


    Pilot’s flight reports can be done separatly under “Pilot Reports” so we are not pushing those message onto everyone subscribed here.


    Note for those posting a forecast: If you also want your posting to be promoted by Twitter and Facebook, send an email to Nicole Boggs (email me for her contact info) who will do this for you.


    Good flights, Jerome.


    Thursday, 2012/9/27. Sunset at 6:37 pm, so launch time sweet spot is 3:37-5:07 pm (from 3 hours to sunset to 1:30 hour before).

    weather.com (San Jacinto hourly forecast) predicts at 4 pm some WSW wind at 8 mph, close to ideal SW wind direction. This forecasting tool has as-good-as or better than NOAA and RASP lately. Not too hot with 85 F predicted.

    SoaringPredictor  predicts SW wind direction. Ideal.

    NOAA wind barbs predicts an ideal SW surface wind direction at 5 pm.

    RASP indicates SE wind at 4pm, SSE at 5pm and SSW at 6pm. Bad.

    Out of the above, I trust most the hourly forecast of weather.com and the NOAA wind barbs.

    Looking at the weather.com 10-day forecast (attached snapshot), rising temperatures relate to Santa Ana conditions (NE flow). The next flyable day may only be Wednesday of next week (Oct 3).


    So in summary…  Get it today while you can.




    Friday, 2012/9/28

    weather.com predicts WNW (bad) from 3pm to 6pm. But morning sledder should be OK with WSW predicted. 10-day forecast shows bad conditions (Santa Ana offshor flow, 102 F on Monday) until return to favorable wind around next Wednesday and then a string of good days.

    NOAA wind barbs for 5pm also indicate WNW wind (bad).

    RASP predict even worse with NE wind between 4 and 6 pm.


    So if unless you want to get morning flights (speed flying), I would not hold much hope today for late afternoon soaring. No need to call in sick at work.




    Saturday, 2012/9/29. A gamble today…

    weather.com which I normally trust, is forecasting a window of WSW (SW would be ideal) between 4 and 6pm, with WNW (not good) before & after.

    NOAA wind barbs predict WNW for 5 pm. Bad.

    RASP predicts a NE flow at 5 pm. Bad.

    Knowing that yesterday blew WNW all afternoon and temperature expected to rise the next 2 days (building Santa Ana conditions)…


    Recommendation: Do not drive a long distance to come to Soboba today, I give a 25% chance of soaring late afternoon.



    So far 3 for 3: Prediction close to observed condition. :mrgreen:. But no worries, I will get it wrong soon enough.

    I stopped by the LZ around 5pm and wind was indeed WNW-NW (not good, just slipping along face of mountain).


    Sunday, September 30, 2012.

    Unless there is an unexpected change, on Sunday I recommend you tell your spouse: “Honey I love you so much I’d rather spend the day with you than go flying“. You will earns lots of points.

    Probably a repeat for Monday.


    Sunday, September 30, 2012. Update. Lots of conflicting forecasts today…

    weather.com predicts light (6 mph) NNE at 4pm and 5mph  SE at 5pm, not good directions in either case.

    soaringpredictor.info flips from E at 2 mph at 4pm to W at 3 mph at 5pm (we want SW). And indicates big altitude gains of 8k over launch.

    NOAA wind barbs puts us close to a no-wind situation at 5pm, but we can average as light West wind (we want SW).

    RASP indicate an East flow at about 10 knots at 5 pm. Bad.


    Making sense of the above:  We are under a light Santa Ana condition (offshore flow from NE). If the wind comes directly over-the-back, we can be in perfect wind shadow at launch and in the LZ with almost no wind, or a side-slip wind to balance and offset from a directly over-the-back wind (NNE wind would add a NW wind component to the convection, for example). So here is  case where you have to judge if the local convection (heating of the side of the mountain we fly) will overpower a light over-the-back wind as you reach the summit of the mountain in flight. I have flown such conditions where everything feels normal on launch and in the LZ (as if a true SW flow) but when you reach the top of the mountain then there is  a definite push from the over-the-back wind. As long as the over-the-back wind is light at mountain top height (less than 10 mph), the turbulence at that level will not be too bad, and one can fly with the lofty goal of reaching high altitudes. But if the over-the-back wind is strong (over 10 mph at mountain top height), then you can be spanked by rotors soon after launching and get a nice taste of shearing winds as you near the summit of the mountain.


    Conclusion: Today is a gamble for being able to launch, hoping that you get a SW flow due to convection or local base wind. About 25% of being launchable. Then from the above paragraph, be ready for some rotor (soon after launching) and turbulence if you do reach the summit of the montain and over-the-back winds there are significant, so only experienced pilots should expore such conditions.


    Remember the saying: I have skill & experience, and will use that skill & experience to keep me out of situations where I need my skill & exprience.


    Monday, October 1, 2012

    From what I saw, it seems like yesterday was WNW (not good) late afternoon, so not good for soaring, as predicted. At 2 pm I saw a 500′ black dust devil on top of the mountain where area was burnt, so wind were probably balanced (over-the-back matched by the convection breeze) at that time on the summit.


    Today… Easy call: weather.com, NOAA and RASP indicate that the wind would be somewhere between WNW and NNE (all bad directions) for this late afternoon. A hot day too (102 F predicted in the shade). So I recommend you shine at work instead.


    Long range: Tomorrow (Tuesday) is a transition day, with predicted West wind (we want SW) so maybe a 50% chance of soaring, but after that there could be a string of good soaring days.


    To all: Please join me in posting forecasts, mine may be late (close to noon) as I am a night owl, and do not not wake up early unless needed.


    Tuesday, October 2, 2012.

    70% chance of soarable late afternoon…

    weather.com predicts WSW (we want SW) at 4 pm and W after (5 and 6 pm)

    NOAA wind barbs show WSW at 5pm

    RASP shows an ideal SW betwen 4 and 6 pm. Ideal.




    Weather.com never did seem to provide great predictions for wind direction in years past, but maybe its time has arrived! NWS 7 day hourly forecast is showing  SW all afternoon. The RASP shows the convergence line to the West of Soboba all afternoon, meaning Soboba will end up in the SW component. The Soaring Predictor site says SW all afternoon, and Windfinder says WSW all afternoon. The Windgram shows W at 3-4pm, then SW at 5-6pm. My favorites are the RASP, because it paints a picture of the convergence,  and the NWS 7 day hourly because it can be centered right on Soboba. The NWS Soaring Forecast gives today an Excellent rating, so we may be in for an epic day!



    weather.com updates during the day, which is nice.

    The guys working there read Bob’s report and then decided to predict a more favorable WSW wind at 10 mph for 4 and 5 pm.  😉


    Today sunset is now at 6:30 pm, so around 4pm is a sweetspot for launching.


    About RASP, I think it gets it rights about 50% of the time,

    I was outside from 2pm- 2:30 and wind was NW around 6 mph at my house (2 miles West of LZ) which is 90 degree in conflict from RASP’s prediction. So pretty diagrams does not imply that the underlying data is correct.


    weather.com predicting WNW up to 3pm and a switch to WSW by 4pm. Let’s hope.



    Every prediction turned out to be wrong yesterday. It was mostly NW all afternoon. Meeting at 4pm to give it another try today!



    Jerome, the RASP does have periods where it is wrong several days in a row, but I think it does much better than 50%. There are many days where the convergence line ends up very near Soboba, and in that case your house could be in the West wind side of it while the site could be in the SW side. We really need a wind talker nearby. There used to be one in downtown San Jacinto that was very handy for telling us SW winds were about to arrive as the convergence line swung from East to West.

    • This reply was modified 7 years ago by  Bob.

    Thursday, October 4, 2012

    weather.com predicts WSW (we want SW) all afternoon until it turns W at 6 pm.

    NOAA wind barbs predict WSW at 5 pm.

    RASP predicts WNW at 4pm, W at 5pm and WSW at 6pm with the convergence line then upon us.


    Overall: Expect some cross-wind from the right on launch during late afternoon. 50% chance of soaring, considering local convection (no cloud predicted this afternoon) will help straighten the breeze.


    Outlook for Friday: Worse. Winds predicted to be more from the West (we want SW). Hey, at least the temperature is cooler now (upper 80’s)

    Weekend outlook: Saturday and Sunday could be better than today and Friday, with a general SW flow predicted.

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