SAN FRANCISCO - The Coast Guard is urging boaters and beach goers to exercise caution in and around the waters of San Francisco Bay and Monterey Bay due to strong swells causing increased rip current conditions and coastal flooding.A high surf warning is now in effect until later this afternoon along the San Francisco peninsula coastline. Westerly swells around 18-28 feet with swell periods of up to 17 seconds are expected today. Swell peaking is expected this morning and will decrease later this afternoon. Extreme wave run up is expected in San Francisco Bay and Monterey Bay increasing the risk of being washed into the sea by waves. Waves are expected to heavily impact the shoreline, resulting in dangerous swimming conditions and rip currents.A high surf warning is also in effect near Rio Del Mar and Pajaro Dunes in the Monterey Bay area until 4 a.m., Saturday. A small craft advisory for hazardous seas remains in effect until 2 p.m., Saturday along the coastline from Point Arena to Pigeon Point. A coastal flooding advisory also remains in effect until noon today for North Bay coastal areas including Point Reyes National Seashore. Flooding impacts of low lying areas such as parking lots and roadways near the bay may occur. Water experts say if caught in a rip current, swimmers are encouraged to swim parallel to the coast to escape the current before swimming for shore. It is advised to always swim near a lifeguard.The Coast Guard offers the following safety tips on the water:* Be aware of weather conditions and monitor the progress and strength of storms through local television, radio and internet. Check the current and expected weather and water conditions before heading out. Be aware that weather conditions can change quickly. * Wear life jackets while on the water. In 2013, 84 percent of boating-related drowning victims were not wearing life jackets.* File a float plan with friends, family members or local marinas before heading out. The list should include the number of passengers aboard the vessel's destination and expected time of return.* Always have a working VHF-FM radio onboard; cell phones may not be reliable once underway.* Do not boat under the influence of alcohol or controlled substances because it can impair your judgment, vision, balance and coordination. Boat motion, vibration, engine noise, sun, wind and spray can accelerate impairment.* Keep children informed of water safety. The Coast Guard encourages the boating public to educate children on water safety. For more information on boating safety for kids, visit www.boatingsidekicks.com.* Dog owners are also reminded to protect their pets from rough waves and not to attempt to rescue their dog from a surf zone. It is important to remember to keep calm and allow the dogs to swim out on their own. For more information on how to protect your pets, please visit http://www.dvidshub.net/video/279770/beach-safety-information-you-your-f... For more information on all watches, warnings and advisories currently in effect, follow this link: http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=MTR&wwa=all * For information on rip current safety, follow this link: http://www.ripcurrents.noaa.gov/overview.shtml