Less than 12 hours after ordering a partial evacuation, fire officials in Calistoga are ordering all 5,000 residents to leave.
Officials issued the alert shortly before 3 p.m., telling all residents to leave and directing them to a shelter at American Canyon High School.
The Tubbs fire caused extensive damage in the hills around Calistoga early Monday, destroying homes, a winery, and a historic resort off Petrified Forest Road and Highway 128 into Knights Valley, but doing no damage to the city itself.
The fire remains well outside city limits but spread on Tuesday to the flanks of Mount St. Helena, north of the city. Forecasters say strong winds were expected to begin as early as Wednesday evening, blowing from the north, which could push the fire into the city.
The first evacuation order went out shortly after 3 a.m. for areas in the northern and eastern parts of the city, affecting about 2,000 people, including guests at several resorts and the remaining evacuees at a public shelter at the Napa County Fairgrounds. The rest of the city was ordered to evacuate after that partial evacuation was completed.
Calistoga Mayor Chris Canning said he was concerned about the potential of the fire spreading to the city, but was "cautiously optimistic" because the active fire is still some miles away.
He confirmed that a report from a San Francisco TV station on Wednesday that some homes in the city had burned was false.
A spokeswoman from nearby Castello di Amorosa, meanwhile, said widespread rumors that the famous winery south of Calistoga had burned were also false.