* WHAT...A long period NW swell will result in an increased risk of sneaker waves and rip currents. Breaking waves will be up to 20 feet in favored locations.

* WHERE...Pacific Ocean coastlines of the San Francisco Bay Area, Monterey Bay, and Big Sur.

* WHEN...From 4 AM Monday through 4 PM Tuesday.

* IMPACTS...Sneaker waves can unexpectedly run significantly farther up the beach than normal, including over rocks and jetties. These waves can suddenly knock people off their feet and quickly pull them into the cold ocean waters, where currents will be stronger than normal. These waves can also carry driftwood logs and other debris.