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ABC7 News Meteorologist Mike Nicco says an unusually cold, early season storm rolling through is having a big impact on the weather.
"It's a very sharp front that's going to kick up some wind when it comes through Wednesday morning with even stronger winds behind it, s aid Nicco. "But, because it's so unusually cold and it's moving so quickly, it's not going to have time to warm much as it descends from higher elevations to lower elevations. That's where we get the compressing of the air, the heating of the air and the drying of the air, which are the three things we associate with our highest fire danger."
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It's going to be warmer than average Thursday. It's just not going to be obnoxiously hot, added Nicco.
Still, don't let cooling temperatures in the Bay Area fool you -- the threat of fire is increasing.
"Today is a day to prepare for what's coming Wednesday, said Nicco. "A Fire Weather Watch has been upgraded to a Red Flag Warning for most of the Bay Area. It's the highest fire designation for critical fire conditions."
The increasing breezes create critical fire conditions Wednesday and Thursday.
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The Red Flag Warning goes into effect tomorrow at 5 a.m. to Thursday at noon. Gusts are expected to reach 45-55 mph and humidity will reach 10-20 percent.
A Fire Weather Watch has also been upgraded to a Red Flag Warning for Lake, Mendocino and Solano Counties.
"Before you go to bed Wednesday night, have your evacuation plan ready, be prepared to lose power. Wednesday night is going to be our most dangerous night for fire, so far this season," said Nicco.