A year or so ago I met Richard Reitmeyer somewhere. I forget where. After a race? Before a race? Then he showed up at an SSS race deck, then at Richmond Yacht Club for dinner. That Richard: He likes boats. Seems he doesn't have one at the moment, so he has agreed to serve on the Singlehanded Sailing Society Race Committee with whoever else shows up.
Last week, when I posted about SF Bay currents and tides, Richard sent this information to me via email. And now I'm sharing it with you. If I had not mentioned Richard I would have seemed smart. But it's not from me. It's from Richard. I'm still waiting for my little book.
Suggested resources and ideas about SF Bay currents for your consideration. Use at your own risk. Not for navigation. Past performance is no guarantee of future results. If symptoms persist, see your doctor. Etc.
* Allen Edwards, the man behind L-36.com, is probably best known for his work on creating and publicising soft shackle techniques, but he also has easy-to-use tide maps. See
https://l-36.com/sf_current_new2.php?menu=9
* At a whole bunch of specific locations, NOAA has tide prediction coefficients (viz the table of them at the back of the book). The next step up from that is to generate harmonic coefficients and do all the math NOAA would do -- but present it in a friendly chart. David Flater did that in the 1990s with a program called XTide, and even better it's still hosted out of the biology department of the University of South Carolina. XTide has coefficients from NOAA and even coefficients back-calculated from people's submitted data. See
http://tbone.biol.sc.edu/tide/ and pick a site like "Red Rock .1 E, San Francisco Bay, California Current" and then fiddle with the options at the bottom of the page. It will do graphs if the site's not too busy, but the tabular form is less impacted by server load and also more compact to put on a cheat sheet if you're doing a lot of locations. You will want the "Current" locations and, if possible, locations in bold type.
* Those are predictions. Predictions are not reality, and so it's also nice to look at what is actually happening. The only place that takes measurements and then shows them vs their predictions is NOAA Ports. There's not many data collection stations, and they're down a lot of the time, but it's the only realtime data availble. You'll see 18 hours of lookback and 6 hours of lookahead in the summary for SF bay at
https://tidesandcurrents.noaa.gov/ports/ports.html?id=9414290&mode=allcurrents and you can 24 hours of lookahead (and often get wind too) at individual buoy locations like
https://tidesandcurrents.noaa.gov/ports/ports.html?id=s08010&mode=composite. If you'll trust "beta" features, you can get predictions in advance at
https://beta.tidesandcurrents.noaa....&tz=LST/LDT&i=&threshold=leEq&thresholdvalue= --- so that's perhaps the most trustworthy data you'll get for 3BF currents near Southampton Shoal.
* The NOAA has an interesting way of bouncing high-frequency radar off the surface of the water and then inferring what the surface currents are doing from the wave patterns. This used to be combined with 48 hours of forward-looking predictions from a big computational fluid dynamic model, forced to fit the latest observations. Sadly, that's been broken for a while at
https://tidesandcurrents.noaa.gov/hfradar/ but fingers crossed it comes back at some point. But you can use the following for seeing "what happened yesterday?":
https://tidesandcurrents.noaa.gov/o...=sfb&subdomain=en&model_type=currents_nowcast -- which is still a CFD model. Or
https://cordc.ucsd.edu/projects/map...n&rng=0.00,50.00&us=1&cs=4&res=1km_h&ol=&cp=1 for something closer to the raw data.
* Competitive racing can be pretty expensive, but World Sailing is trying to level the playing field by combatting apps or sites that could cause damage to a boat's chocolate candy capacity. You can use them before you start racing, but after the prep signal it might be best to turn them off and look at the sites above. See Rule 41 "A boat shall not receive help from any outside source, except ... c) help in the form of information freely available to all boats;" and World Sailing Case 120, specifically:
Information for which a fee has been paid or that is not easily obtained by all boats in a race is not “freely available.” Examples are information supplied only to those boats that have paid a subscription or other fee, and information whose source is obscure.
Good luck out there!
