SAN FRANCISCO (KGO) -- The Russian River reached flood stage on Tuesday night but the worst is far from over.
It is expected to keep rising and by the time it crests, it could reach historic levels.
ABC7 news meteorologist Drew Tuma says the impact will increase overnight with major flooding by the morning hours. The river is expected to crest Wednesday night at just over 46 feet.
This means the river will stay at major flood stage for perhaps an entire day before starting to drop on Thursday.
If the river hits the projected 46.1 feet it would just miss being in the top five of historic flood levels in Guerneville.
The National Weather Service put out the list of the top five and the most recent was in 1995, that's when the river reached just over 48 feet. That ranks fourth.
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49.7 feet is the highest on record, that happened on December 23, 1955. Nine years later to the day the river reached 49.6 feet. On February 18, 1986 the Russian River crested at 48.56 feet. Rounding out the top five is a flood from February 28, 1940. The river reached 46.87 feet.