People near Thunder Valley Casino outside Lincoln reported seeing a funnel cloud at about 2 p.m. Monday.
Twitter users who posted photos said the funnel cloud was west of the casino.
The National Weather Service posted one of the reports along with a photo on Twitter. A spokesman said there was no indication that the funnel cloud touched down in the area.
A high wind advisory has been issued for the Sacramento Valley for late Tuesday morning through Tuesday evening. Winds of 30 to 40 mph are forecast, with gusts up to 60 mph.