When I was in junior high school in Greenwich, Connecticut, I had classmates who thought it was fun to take a sunfish (the small boat, not the animal) out during small craft warnings. I thought then - and still think now - that they were idiots. I was accidentally caught out on the water in a sunfish during a storm once. It was one of the scariest experiences of my life, and we were well inside Greenwich Harbor when it started. The storm blew in out of nowhere; the sky suddenly turned almost pitch black, the rain was falling so hard that it felt like hailstones when it hit my skin, and the winds were high enough to blow sunfish hulls off their racks on the shore. The storm didn't last long, but I'd guess the winds were somewhere in the 65-75 mph range. It's a tribute to my father's sailing ability that he got us (the poor guy had all three of his daughters with him) and the boat on the beach in one piece.
Technically, there is no such thing as a small craft warning. The scale goes: small craft advisory (varies by location; in California, winds 21-33 knots), gale warning (winds 34-47 knots), storm warning (winds 48+ knots) and hurricane warning (winds 74+ mph). Except for hurricanes the speeds are given in knots (nautical miles per hour) rather than miles per hour, probably because anything less than a hurricane doesn't require people on land to take major action such as evacuation. Or to know what "knots" means.
There is also no legal definition of a "small craft." The practical definition given by the National Oceanic and Atmospheric Administration is "any vessel that may be adversely affected by Small Craft Advisory criteria."
The America's Cup should have ended today, and that was worst case planning. It allowed for seventeen races, as the first team to reach nine points wins. It had reserve days built in to allow for bad weather. It just didn't allow for enough bad weather, because there are up to six races still to go. There have been three races abandoned (stopped after they started) because the winds were too strong, and one because the winds were too light and the leader didn't reach the finish within 40 minutes after the start. In all four cases, the leader was New Zealand. I have lost track of the number of races that have been postponed (stopped before they started) due to too much wind. Today there were no races sailed at all. The top allowable wind speed is approximately 23 knots, adjusted by a factor for the current speed and direction.
Bravo, Oracle! You've invented the 72-foot small craft.