It's Friday, January 29, 2010. Today the moon is full, and some extreme tides are predicted. Check the tide plot above for Santa Cruz. It's from the Biological Sciences web page at the University of South Carolina. The web interface is by Dean Pentcheff, and it utilizes the XTide program by David Flater. This is one of the best tide prediction sites, offering tide charts from numerous locations on all coasts of the United States.

The chart shows some extreme tides for this day of the full moon. Indeed, the entire weekend will exhibit similar levels in the ocean. There's a predicted high of 6.5 feet at 9 AM Friday morning, falling to a predicted low of -1.5 feet at 3:45 PM Friday afternoon. This is an astounding 8 feet of ocean level change in less than 7 hours. Obviously there is an affect on the surf in Santa Cruz for the day.

In fact, this stretching of the tide levels is due to the perigee in the Moon's orbit around the earth. The orbit is not circular, but elliptical. Perigee is the point at which the Moon comes closest to the Earth, which is 31,000 miles closer than the opposite side of the orbit.Today, the perigee comes during a full Moon, so it will be larger in the sky and brighter than other full Moons. The close proximity of the Moon increases the tug of its gravity, thereby inceasing the effect on the tide levels.

Many surf breaks bog down into mush when the tide is too high. There is just too much water on top of the reef for the waves to break crisply. Not only that, many spots actually break offshore from cliffs and shoals. When the tide is too high, the waves don't break so much in front of the rocky shore as they break onto and over the cliffs. It's also problematic to enter and exit the water when the waves are slamming the shoreline walls.

Later in the day, many spots will begin to fire with the lower tides. Shallow reefs will begin to push the swell up and over; waves will break top to bottom. You can bet the surfers will be on it. Small wave long board spots such as Cowells will become wetsuit conventions for a time.

But the ebb of the tide at -1.5 feet is too low for a lot of surf breaks. The reefs will poke through the water here and there, turning boils into real hazards. Beach breaks will still offer opportunities; sandy bottoms and bars will just force the action further into the ocean from the shoreline.

The rate of the tide change, more than one foot per hour, will dictate which breaks are surfable at which times. For a lot of places, the window of opportunity will be rather narrow, maybe as little as an hour or so. If you have the time, you could hang at your favorite spot and wait and watch. As tide falls the optimum conditions will present themselves and you paddle out.

If you can only spare a couple hours, but are flexible as to when it is, you can predict when your favorite break will likely fire. Then you appear at the appropriate time, surf for an hour or two, and get back to your other responsibilities.

If you only have a certain hour available, then you have to suss which of the many breaks will be going off at that particular time. In this way you can still have a decent session and get your waves.

With tide conditions such as these, your local knowledge will be your best tool for getting the best waves. And that is how it should be. The rest of the weekend will be similar, so get busy!

CU Out There,

DogMan