A common pattern for good summer days is to have 5-10 knots W to NW during the night and morning, often with a lull around noon where the wind drops and shifts to N to NE. In the next two hours the wind will swing around to NW and pick up to 15 to 20 knots between 2 and 6 pm. If the sky is clear or low clouds are clearing, a good morning breeze (NW 8-10 knots) usually means a good afternoon wind. When the marine clouds come far into the bay (e.g., morning overcast over the whole bay), SFO may remain under the clouds and have fairly mild wind readings (~~15 knots) all afternoon, but Coyote and 3rd can be cranking if they are beyond the clouds. This is most easily seen from the multi-city "sky" sections: if SFO is reporting *low* clouds (e.g, "9 sct" or "8 bkn") then it is under the marine clouds. If Hayward is clear, then the cloud line is somewhere over the Bay, and Coyote and 3rd are probably blowing hard. The clouds run in a stream only a couple of miles wide from SFO to Hayward; about the time the clouds get to Hayward the wind at Coyote and 3rd will shut off. When we get very thick marine layers, we will often get fog coming over the hills way down the peninsula. This often causes a west wind over much of the Peninsula, but may cut off Coyote (wrong direction for the NW-facing San Bruno gap, plus the wind is more diffused). This will generally show up as a SFO wind direction less than 290. Sometimes Oyster Point and Flying Tigers will blow in this case, and the winds can be higher than those recorded at SFO. 3rd Ave can also have significantly steadier winds. If the fog is coming over the hills as far south as Woodside, then Palo Alto is a good bet. Wind on the water is generally 2-5 knots more than that recorded at the Palo Alto airport. Depending on where the fog line is, other good locations may be Crissy or Berkeley. If the fog/clouds are coming well inland each night, Rio Vista and San Luis Res are generally good. These locations tend to crank up late in the afternoon (4 to 6 pm), blow all night and subside sometime mid-morning. They fairly often get over 25 knots. In the winter, look for storms with good rotation. Before it hits, go to Half Moon Bay for flat-water sailing in the south winds. After it passes by, go to the usual summer spots (Coyote, 3rd, Crissy, etc) and sail in the clearing NW wind. All you get is 3-8 hours on either side, so you have to move quick. Sometimes we also get just a major W or NW jet-driven wind which can last longer. === Airport readings vs wind at sailing sites === Winds near Coyote point typically are well correlated with SFO numbers. This is not surprising, since Coyote is just 3 miles downwind from SFO. The major gotcha is that there is a wind line caused by the southern edge of the San Bruno gap which is near the shore at Coyote for the typical direction of 290. Wind directions of 310 or more tend to bring the wind all the way to the shore. Directions less than 290 will decrease the wind at SFO somewhat, but they tend to move the wind line way offshore at Coyote, making the wind line a mile or two offshore for a direction of 270 or less. In these conditions, Coyote can be practically becalmed. I think winds at Crown Sterling tend to follow the same pattern, but I don't sail there often enough to say for sure. Winds in the channel at 3rd Ave are generally best correlated with the SoSF_SBrMt readings. This is the same instrument as the 118.05 MHz "shoreline departure" radio station, which is 800 feet up on San Bruno Mountain. The major exceptions occur when stratus clouds ("fog") get very close to the mountain - the readings get gusty as the clouds approach and they can drop quite a bit if the clouds completely envelop and pass San Bruno Mountain. You can tell when this happens because the temperature gets down within a few degrees of the SFO dewpoint temperature, usually about 55 F (the ocean temperature). The direction at the San_Carlos station is useful for telling if the wind is blowing over the highway 92 pass by San Mateo. When 92 is blowing, San_Carlos reads about 280; when it is not, San_Carlos gets 330 to 020. This is about twice as much directional shift as we see at 3rd under these conditions. The windspeed at San_Carlos seems to be 3-10 knots less than at 3rd, so it is not very helpful. For Tigers/Oyster, SoSF_SBrMt works well, especially on due west or slightly southwest. If it goes 320 or more northerly, it shuts down there.