SAN FRANCISCO (CBS SF) — Smoke from numerous wildfires in the North Bay is affecting visibility Thursday at San Francisco International Airport, resulting in many delays and cancellations, an airport spokesman said.

As of mid-morning, 81 flights had been canceled and about 10 percent of flights were delayed an average of 30 to 45 minutes, SFO spokesman Doug Yakel said.

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The number of cancellations is about evenly split between arrivals and departures.

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Smoke from the wildfires has not affected operations at Oakland International Airport, but two flights from San Francisco International Airport have landed in Oakland because of the problems at SFO.

A spokeswoman for Mineta San Jose International Airport said she had not heard of smoke affecting any flights there today.

No impacts were reported Wednesday either, spokeswoman Rosemary Barnes said.

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