NAPA VALLEY, CA (WTOC) - Wildfires are common across the west this time of year. But, the disaster that unfolded across portions of northern California Sunday and Monday was created by a variety of unique factors.
Winter 2016-2017 was abnormally wet across the west. A Super El Nino event contributed to this event. The wet season allowed vegetation to flourish. Unfortunately, the new plant material dried significantly once rain diminished. It became tinder during the dry season, adding fuel to the fire.
Fires were ongoing before the news made headlines. A strong Diablo wind event developed late Sunday, into Monday. This particular wind event is specific to areas of northern California, similar to southern California's "Santa Ana" wind events.
Strong northerly winds, with gusts up to 80 MPH, swept down higher elevations of Sonoma, Napa and surrounding counties. This wind motion created a strong down-sloping effect. Air heats and dries as it is forced downward.
As the warm, dry, damaging wind gusts interacted with ongoing fires, blazes spread rapidly towards populated areas.
Falling power lines, etc., also contributed to fire growth as sparks and wind-blown embers ignited new fires. All the above factors created the fatal firestorm that destroyed portions of the 'North Bay'.