The National Weather Service said the new flood watch is in effect from 4 p.m. Tuesday through noon on Thursday, while an existing flood warning also is in effect, with no time yet set for its expiration.
The forecast calls for moderate to heavy rain Tuesday night through Wednesday. That additional rain increases the potential for flooding, as streams, creeks and Clear Lake already are running high or at flood level.
The vast Mendocino Complex burn scar also could experience mud, rock and debris flows, especially if thunderstorms develop over the region on Wednesday, the National Weather Service said.
Early Tuesday, Clear Lake was at 9.80 feet Rumsey. Flood stage is 9 feet Rumsey, the special measure for Clear Lake.
The forecast calls for the lake’s level to rise to near 10 feet Rumsey on Wednesday afternoon, with continued rise expected.
The specific Lake County forecast calls for up to a quarter of an inch of rain during the day Tuesday and up to 2 inches Tuesday night,
More steady rainfall is forecast for Wednesday, along with light winds, as well as Thursday.
Thursday night, the rain is expected to break, with slight chances of rain from Friday through Monday.
Nighttime temperatures will range from the high 30s to the mid 40s, with daytime temperatures from the high 40s to low 50s expected.
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