The museum held a walk-thru for members of the media on Tuesday. It is scheduled to open to the public on April 17.
The new, 330,000-square-foot museum at Pier 15 along the Embarcadero has three times more space than the previous location at the Palace of Fine Arts in the city's Marina neighborhood, according to an Exploratorium statement.
It includes an all-glass observatory and a gallery with views of the waterfront and city.
The rain chamber is among 150 new exhibits. Visitors select a past storm and the exhibit recreates the frequency, size, and velocity of its raindrops.
Another new exhibit, also part of the museum's outdoor gallery, explores the different colors of San Francisco Bay.
"The Color of Water" consists of 32 distinct color swatches suspended above the water, allowing visitors to match the day's water color and investigate what causes it to change from day to day.
Construction on the new facility began in 2010.