Did you know there isn’t a “standard” definition of a Small Craft Advisory (SCA)? The criteria used to issue a small craft advisory is dependent upon geographical location and may include wind, wave, and/or ice conditions. According to NOAA’s National Weather Service, in California (including San Francisco Bay) the criteria is “Sustained winds of 21 to 33 knots, and/or wave heights exceeding 10 feet (or wave steepness values exceeding local thresholds.” If you have ever taken Advanced Coastal Cruising, you know Tradewinds won’t allow you outside the gate if wind is 34 knots or higher, wave heights are greater than 12 feet, or period (steepness) is less than 9 seconds. The above NWS guideline is why. A 42 foot boat may seem big, however, it is still considered a small craft.
Here on the bay, we are spoiled by daily winds in the range of 25 to 30 knots from May through September. Which means if we wait for a day that is not a SCA we have to wait until October to go sailing! If you are like me, you don’t wait. You relish those days of guaranteed consistent wind, sheltered from the waves and swells that normally accompany big wind!
Unfortunately, sailing all summer during Small Craft Advisories tends to lessen our appreciation of what it really means, leading to an “I sail in SCA days all the time, I can easily handle it.” And then we run into a winter SCA! Small Craft Advisories in the winter ARE NOT the same animal as during the summer. Winter storms bring sustained winds in the SCA range with gusts often times well into the Gail Force range (34 to 47 knots). In the winter, conditions can easily escalate in a matter of minutes. I remember one time on Windfall cursing the fact I had under 5 knots. Less than 15 minutes later, unable to control a boat under full sail with over 35 knots of sustained wind and much higher gusts I was genuinely afraid for my life (and that of my then 14 year old daughter!) I also remember another SCA winter day that I made the decision to keep the boat in the slip, drink coffee, and fellowship with some good buddies on the boat, while listening to mayday calls all day long. In one of the calls, a schooner had lost both masts and was being driven toward Red Rock. The USCG got to them minutes before the boat would have been driven onto the rocks.
So here is this week’s tip. Go ahead and brag about your skills by saying things like “If I waited until there wasn’t a SCA I wouldn’t be able to sail until October.” But, when winter rolls around and you see a SCA in the forecast, consider staying inside by the fire instead of going sailing!
Great article Don and good reminder. Thanks for taking time to publish these.