The National Weather Service says there's a 90-percent chance a tropical system south of Baja will become a cyclone in the next 48-hours.
Once that happens, forecasters say it will follow one of two paths.
Spin away from the coast of San Diego, the favored prediction or spin into it.
They say higher waves and possible coastal flooding is expected for the weekend, but rain totals are still uncertain. Meteorologists say tropical swells are roughly forecast to arrive Saturday or Sunday and will coincide with high tides of more than six feet.