Green Flash Sunset

Don’t Miss a Possible Celestial Surprise on Saturday, November 8, 2025

The setting sun may treat us to a rare optical spectacle at the Berkeley Yacht Club, as it sinks toward the horizon and aligns for a clear view through the bridge.

With the sun visible down to the horizon line and the open water view from the clubhouse, this may be a very favorable setting to catch the elusive “green flash.” 

What is the Green Flash?The “green flash” is a fleeting optical phenomenon that can occur just after sunset (or just before sunrise) when the upper rim of the sun briefly appears green for a second or two. It’s caused by the way sunlight is refracted and scattered in Earth’s atmosphere. As the sun gets very low on the horizon, its light must travel through a much thicker layer of atmosphere, which acts like a prism, separating colors of light. Because the shorter-wavelength blue and green light are refracted more. Sometimes a brief green flash is visible just as the rest of the sun disappears.

Factors That Increase the ChancesHere are some of the conditions that increase your odds of witnessing the green flash:

• A clear, unobstructed view of the horizon (ideally over the water) with the sun sinking directly toward that horizon. Farmers' Almanac+1

• Minimal haze or cloud cover near the horizon line, so the sunlight isn’t overly scattered. EarthSky+1

• Stable air layers and, sometimes, a gentle temperature inversion near the surface, which can act like a mirage amplifier. GG Weather

• The sun’s disk being visible down to the horizon line (rather than setting behind a hill or blocked by buildings). That kind of horizon line is crucial.

Given that from the Berkeley Yacht Club you have a view over the water and a direct line toward the horizon through the bridge, you are well-positioned for just such an event.

Saturday Viewing Tips

• Arrive a bit before sunset — check local sunset time for November 8 and aim to be settled at least 10–15 minutes before.

• Choose a spot with a clear, unobstructed view westward.

• Use binoculars or a camera with zoom if you have them. Never look directly at the sun without appropriate protection until it is touching the horizon.

• Be ready for the moment just before the sun disappears. That is when the green flash, if it happens, will show: a brief green flicker at the top edge of the sun’s disk.

   

  Even if you don’t see it, the sunset views will be beautiful!