Locations to be affected: Reefs and exposed mainly northeast-facing coastlines with relatively shallow, gently to moderately sloping near shore areas.

Timing: Until 6 pm today.

Synopsis: Moderate long period swells are reaching the area, affecting mainly northeast-facing coastlines. The threat level to the life, livelihood, property and infrastructure of those using the affected coastlines is moderate, with the potential for significant impacts. These swells are expected to cause life-threatening surfs and rip currents near affected coastlines. A high surf advisory means that dangerous surfs of 2 to 3 metres or 6 to 10 feet will affect some coastlines in the advisory area, producing hazardous conditions.

Seas (significant wave heights): 2 to 2.5 metres (6 to 8 feet), occasionally or locally reaching 3 metres (10 feet). Swell period: 9 to 15 seconds. Swells: Northeast at 1.2 to 2 metres (4 to 6 feet) and occasionally higher.Surfs (breaking swells): Over over 6 fee). These conditions are conducive for dangerous rip currents. Please note that surfs could be as much as twice the height of swells, depending on the bathymetry of the near shore areas.Coastal flooding: High tides combine with onshore wind and swell actions could result in localized coastal flooding and beach erosion.

Potential Impacts: Loss of life–strong currents that can carry even the strongest swimmers out to sea; injuries to beachgoers; beach erosion; sea water splashing onto low lying coastal roads; beach closures; localized disruptions to marine recreation and businesses; financial losses; damage to coral reefs; saltwater intrusion and disruptions to potable water from desalination. High surfs can knock spectators off exposed rocks and jetties.

Precautionary: Beachgoers should be extremely cautious; bathe only where lifeguards are present or the sheltered, less affected beaches, mainly to the south and west.

Rip currents are powerful channels of water flowing quickly away from shore, which occur most often at low spots or breaks in the sandbar and near structures such as groins, jetties and piers. If caught in a rip current, relax and float. Don`t swim against the current. If able, swim in a direction following the shoreline. If unable to escape, face the shore and call or wave for help.

Forecaster: Dale Destin