9:43 a.m. PDT Sept. 10, 2021
Lightning, strong winds, and showers moved into California, Nevada, and Oregon Thursday afternoon. Friday morning at about 7 a.m. the National Weather Service reported approximately 1,100 ground strikes had occurred in California.
Most of Northern California and Central Oregon received at least a small amount of rain. While some weather stations recorded none or less than 0.05″ others measured more than 0.25″.
All of the precipitation amounts below are for the 24-hour period ending at 7:10 a.m. PDT Sept. 10.
Maps of precipitation in California and Oregon–
The huge 928,000-acre Dixie Fire, which is 70 miles wide, had amounts ranging from zero to 0.55″.
With fuel moistures being historically low, it will be only a matter of days before most of these areas dry out and holdover fires ignited by lighting will be appearing. This is not enough rain to completely extinguish the existing fires. Where rain did reach the ground, spread of the fire in those locations will be slowed temporarily, but in the coming days or weeks, if there is no additional precipitation, they could be just as active as before. This respite from extreme fire behavior will give firefighters the opportunity to aggressively construct firelines directly on the fire’s edge, stopping the spread in those areas.
In Northwest California amounts on or near the River Fire were from zero to 0.43″. A rain gauge near the Antelope Fire had 0.36″. To the west of the Antelope Fire, the Lava Fire at Mt. Shasta which has been contained for weeks, had 0.40″.
The 218,000-acre Caldor Fire, which is 43 miles from east to west, had precipitation ranging from zero to 0.36″, with a tenth of an inch in the South Lake Tahoe area.
A forecast for the six-hour period ending at 11 a.m. Friday shows additional rain — more than half an inch in central Oregon.
In most areas the chances of lightning, thunderstorms, and rain will be decreasing throughout the day on Friday. The wind will be strong, gusting out of the southwest at more than 20 mph.