By John C. Toman. Posted October 19, 2011, 6:32 AM.

The National Weather Service has issued a dense fog advisory through 10am Wednesday morning for some of Southern California's inland valleys, which could make for dangerous driving conditions.

Affected areas to the south include the Temecula Valley, potentially spilling into Menifee and Wildomar, Fallbrook and De Luz.

To the north, Ontario, Chino and Corona had dense fog to start the day.

Visibilities in the affected areas are predicted to be a quarter of a mile or less. Travel on Interstate 15 will be the most impacted.