Fire watches, warnings renewed across California.
An unusually persistent pattern of high pressure continues its grip on much of the western U.S. and for weeks, winter smog, haze, and fog has been the product of a widespread temperature inversion.
Much of eastern Washington State, portions of Oregon and Idaho have been under air stagnation and dense fog advisories for the past week, due to little or no atmospheric mixing, with very little change indicated in the near future.
Utah is also experiencing unusually strong and persistent temperature inversions, Salt Lake City has instituted urgent recommendations regarding the operation of motor vehicles, urging its citizens to refrain from unnecessary driving, even restricting prolonged idling.
In California, conditions of extreme drought continue. A weak disturbance aloft moving through the Rockies will only serve to reinforce cold air across the western plateau, potentially bringing more dry gusty offshore winds to much of the state.
Once again, a fire weather watch will be in effect for much of southern California beginning Thursday for developing Santa Ana winds, low humidity and above average temperatures.
In central and northern California, a red flag fire warning begins at 10 pm this evening for areas immediately north and east of San Francisco, and a fire weather watch will cover widespread areas from the Oregon border south and east to near Yosemite National Park.
Surface weather models trend towards a moderate to strong offshore pressure gradient through Friday across much of California. Beyond that, a continuing pattern of settled high pressure appears to be the scenario for the western U.S. for the rest of January.
Long-range models hint at the possibility of changes early in February, and the statistical odds are in its favor. But meteorologists caution that beyond ten days, it's pretty much “anyone's guess.”