King tides along the coast of B.C. will reach their highest levels on Christmas morning, prompting a warning to seaside residents to be on alert for flooding.

Two weeks ago the seasonal tides combined with a storm surge to flood shorelines across the South Coast of B.C., triggering local states of emergency in Delta, Courtenay and Campbell River.

Municipal workers in Vancouver also put down 30,000 sand bags along low-lying areas near Locarno Beach, but flood conditions never materialized. The city left the bags in place for the king tides expected on Christmas Day.

While there is no storm in the immediate forecast for coastal areas of B.C., the high tides forecast around Vancouver on Dec. 25, 26 and 27 are forecast to reach five metres. The sandbags will remain in place until mid-January, the city website says.

King tides are extreme high tides that happen about twice a year when the sun and moon's gravitational forces reinforce each other.