Thousands of Bay to Breakers runners braved the rain like Angel Sanchez and his dad from Richmond.
"It's not that heavy now, it might be hailing later," said Angel Sanchez.
The weather may have kept some race course spectators away, especially over the grueling Hayes Street Hill.
"With the rain, there was less partiers to keep you motivated, you had to fight on and cheer on each other," said runner Amanda Bermudes.
22-year-old Gabriel Geay was the men's winner at 35:01.
35-year-old Carolyn Rotich was finished first for the women at 39:28.
RELATED: 'We're just going to go for it' Bay to Breakers runners brace for the rain
We spotted some clever costumes on the race route; super heroes, pandas on the loose, an order of tacos and a gaggle of Judge Ruth Bader Ginsbergs.
Security teams enforced the no alchohol rule on the racecourse, confiscating booze from people and tossing it.
By mid-morning the rain tapered off and the sun came out.
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