North Sails NEWS
J/24 WORLDS LOCAL KNOWLEDGE
Get To Know Biscayne Bay
To help you prepare for the 2019 J/24 Worlds, we asked the local Star and Snipe World Champion Augie Diaz to explain about his home waters of Biscayne Bay in Miami, FL.
Biscayne Bay is I think pretty straightforward. The weather is driven by cold fronts approaching, and we don’t get as much breeze as we used to because the city’s grown so big. But generally, any breeze from the northeast around through the southwest is great sailing. From this direction, the breeze is usually under fifteen knots, with relatively flat water (chop but no swell). Spring and fall are the best seasons, because we don’t get many fronts.
Dominant wind direction: easterlies
The old rule of thumb is still the case: if the wind’s to the left of the south end of Key Biscayne, you go left. Near the Key, from 120-160 degrees, there is a little more pressure closer to the end of the Key, and also a geographical shift off the land. How favored is somewhat current-dependent; from 70 degrees to 160 degrees with an outgoing current, then left is really good, what we call the “Old Man Expressway”. [“The Old Man” is Augie’s father, Gonzalo Diaz Jr., who discovered back in the 1960s that stepping up to the left in these conditions was a race-winning move.] At the top of the beat on the J/24 Worlds course, the Old Man Expressway could be important.
On what I call the Cuba Course, where the Etchells sail, way down south of Matheson Hammock, there’s less left down there than there is closer to the point of Key Biscayne. So you have to keep in mind where you are on the Bay.
Understanding the current is very important. People think the current comes in and out of the Bay from the east, but it actually runs in and out from Bear Cut. If you get close to what we call the Valves, which are the channels through the shallow areas that on the chart are labeled Biscayne Flats, there is a component of current going in and out of there. But you have to be very close to the Valves for that to be the net effect. Otherwise, the current basically ebbs from the southwest to the northeast, and goes the opposite way when it floods.
As for the timing relative to high and low tide, I’ve seen it as much as an hour off, so I just use tide change as a gauge and then keep checking the buoys, all the time. Sometimes seaweed will show lines of current, but I’ve never really seen a change in the color of the water.
Other wind directions
Once the wind gets to about 170-180, it’s pretty important to protect the right. That’s true all the way to 220 degrees. Anything right of 220-230, it’s going to march quickly to the northwest because that’s a frontal-driven direction, which doesn’t doesn’t have the ability to stick.
If the wind’s right of 230 degrees, I like coming in from the top left because you get some really nice puffs off the left shore. It depends where you are on the Bay; on the J/24 course, close to the west shoreline, you’ll definitely want to come in from the top left.
Northwesters are like you’re on a lake: very shifty, very up and down. But in late October, it’s actually less frontal, so that’s less likely.
Secret to success
Focus on what the current’s doing, and in the easterly understand how important it is to go left.