San Francisco County · Outer Sunset / Richmond
Ocean Beach
Open Coast · 3.5 Miles Long · GGNRA Seasonal Patrol · Extreme Rip Currents
⚠ Data may be stale — showing last known reading. Conditions may have changed.
Wave Height
—
feet
Swell Period
—
seconds
Direction
—
swell from
Water Temp
—
°F
NOAA Buoy 46026 — San Francisco Bar
Long-period swell is dangerous. Any swell period above 15 seconds means waves are arriving in sets with long quiet intervals — sometimes 20 minutes of calm. During the quiet, energy is building offshore. People who walk to the water's edge during the lull are swept in when a set arrives.
Known Hazards
Long-Period Swell
Read the swell period in the chart above. Waves arrive in sets separated by long, quiet intervals. During the calm between sets, people approach the water's edge and are swept in when the next set arrives.
Source: NPS GGNRA / SF Fire Dept — Joint Coastal Safety Advisory (sf-fire.org); NOAA NWS Beach Hazards guidance
Permanent Rip Currents
Rip currents are present along the entire length of Ocean Beach at all times — there is no period when they are absent. GGNRA Ocean Rescue personnel confirm there is never a moment when rip currents are not present here. People have been swept out to sea in three feet of water. Swimming is strongly discouraged. Fatalities occur here most years.
Source: NPS GGNRA / Golden Gate National Parks Conservancy — "Hidden Dangers of Ocean Beach" (parksconservancy.org); SF Fire Dept / NPS Joint Coastal Safety Advisory (sf-fire.org)
Cold Water
Water is cold year round. Hypothermia can set in quickly.
Source: NPS GGNRA — Ocean Rescue / Joint Coastal Safety Advisory (sf-fire.org)
No Year-Round Lifeguard Posted
GGNRA lifeguards patrol seasonally. There is no year-round posted lifeguard. Emergency response times on remote beaches may take longer than in urban environments.
Source: NPS GGNRA / CA State Parks — Beach Safety Practices (nps.gov/goga); SF Fire Dept / NPS Joint Coastal Safety Advisory (sf-fire.org)
Before You Go Near the Water
01
Read the swell period before you approach the water. The number in the chart above is your warning. A period of 15+ seconds means sets are arriving with long, quiet intervals between them — sometimes up to 20 minutes of calm. During the quiet periods between sets, energy is building offshore. People who walk to the water's edge during the lull are swept in when a set arrives.
02
Watch the ocean. Stay on dry sand. Do not approach wet sand or the water's edge until you have watched the ocean and learned the rhythm of the sets.
03
Wet rocks or sand mark where the ocean has already been. If the rocks or sand are wet, a wave reached them recently. Stay above the wet line — always.
04
A long wait between waves is a warning. During long period swells, the ocean may appear completely calm between sets. If it has been calm for several minutes, stay back. Do not walk toward the water.
05
Keep dogs on leash. Keep dogs on leash and away from the water's edge.
06
Tell someone your plans. Leave your destination and expected return time with someone before you go.
07
Rip currents do not always look dangerous. They can appear as calmer, clearer water with less white water than the surf on either side — which can make them look like a better place to swim. They are not. If you see a break in the surf line with calmer water, stay out.
How to Read Sets
Long-period swell doesn't produce a steady stream of waves. It travels in sets — groups of larger waves separated by long, quiet intervals. At 15+ seconds, those intervals can stretch to 20 minutes of calm. During the quiet periods between sets, energy is building offshore. People who walk to the water's edge during the lull are swept in when a set arrives.
1
Find a high vantage point above the water line. Do not approach the shore first. Watch from above.
2
Time the quiet intervals. Count the seconds — or minutes — between large waves. This is your set interval.
3
Watch for at least 15 minutes. You need to see multiple sets before you understand the rhythm. One quiet stretch means nothing.
4
The largest wave in a set is not always the first. Sets build in size. The final wave is frequently the biggest.
5
When in doubt, stay back. At 15+ seconds period, stay completely clear of the shore and any rocks.
6
Long-period swells create “sneaker waves,” sometimes called “sleeper waves,” because they produce sets of waves separated by long periods of relative calm. That calm can create a false sense of security — people approach the shore and are not anticipating the next set when it arrives, leaving no time to retreat. These circumstances are predictable and deaths from being swept in are preventable.
Ocean Emergency
911GGNRA Dispatch · (415) 561-5505
USCG San Francisco · (415) 399-3547