SAN FRANCISCO (CBS SF) – Bay Area residents were treated to a rare sight Wednesday evening: a double rainbow.

Visible throughout the region shortly before 7:30 p.m., the bright arcs made for an impressive sunset as a storm front moved through the area, National Weather Service meteorologist Steve Anderson said.

The same weather system sparked lightning in the South Bay throughout Wednesday, and then again early Thursday morning in San Jose and Livermore, Anderson said.

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The storm system is expected to pass through the Bay Area by midday Thursday, with dry weather forecast for the next week. Temperatures are expected to heat up mid-month and into October, Anderson said.

San Francisco Giants fans watch the game against the
Arizona Diamondbacks at AT&T Park on Wednesday under the halo of a double
rainbow in the sky behind them. (BCN)

Social media has been abuzz since Wednesday evening when the angle of the rainfall relative to the sun created the stunning display of colors.

Photos of the double rainbow were captured and posted online from the Giants game at AT&T Park in San Francisco, various San Francisco neighborhoods including Potrero Hill, Bernal Heights, the Presidio, Nob Hill and the Financial District, and from parts of Alameda and Contra Costa counties.

Anderson said the visual effect of a double rainbow occurs when another patch of rain falls in front of the first arc, creating the appearance of two arcs.


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