It's the time of year when the sun and moon reach their closest points to Earth, aligning the celestial bodies like a perfect cue shot to create maximum gravitation pull.

The resulting extreme high and low tides, called king tides, usually occur in December and January. They're in the forecast for the Bay Area Friday though Sunday.

The highest tide will happen on Friday at 10:22 a.m. and again on Saturday at 11:07 a.m., with a sea level rise of 6.7 feet. Sunday is expected to see a sea level rise of 6.6 feet at 11:54 a.m. These will be followed by low tides: -1.25 feet at 5:19 p.m. Friday, -1.36 feet at 6 p.m. Saturday, and -1.29 feet at 6:43 p.m. Sunday. The level of the sea will shift some eight feet in a little over seven hours each day.

"People going to the beach when the tide is lower need to be careful to not get trapped when the tide comes back in," said Spencer Tangen, a forecaster with the National Weather Service office in Monterey.

While the National Weather Service predicts tides well over 6 feet in coming days, other meteorological factors such as a storm surge can raise them even higher. Tangen said the tides will likely be slightly higher than the astronomical prediction, but a major storm surge in the Pacific isn't expected in coming days so the impact will be minimal.

Minor flooding is expected along the immediate coast and bayfront during the king tides. "Most of the known impact locations are in Marin County on the bay side. There are quite a few roadways close to the bay that can start to see water. Along the Embarcadero in San Francisco, we are expecting very minor flooding in low-lying areas."

Ahead of the tides Caltrans closed the lower half of Manzanita Park & Ride in Tamalpais Valley Junction through January 14.

Amy Graff is a digital editor with SFGATE. Email her at agraff@sfgate.com.