Waymo says it will soon begin piloting autonomous cars in Florida, expanding from its initial test cities of Novi, Kirkland, Washington, San Francisco and Phoenix.

The company says in the coming weeks it will bring both its modified Chrysler Pacifica minivans and a Jaguar I-Pace to drive on a closed track in heavy rain, ahead of tests on public Miami roads later in the month.

“At Miami-Dade County, we are constantly exploring ways to improve and provide more mobility options for our community,” said Miami-Dade County department of transportation and public works director, Alice Bravo. “I’m supportive of Waymo’s presence in the county as they continue to push technological boundaries and discover new ways to help us move.”

Waymo says its cars will be manually driven by trained operators, giving the team an opportunity to collect real-world driving data in heavy rain. When the cars venture beyond the closed track, they will mainly drive on highways between Orlando, Tampa, Fort Myers and Miami.

Waymo points out during the hurricane season in the summer months, Miami is one of the wettest cities in the US, averaging an annual 61.9 inches of rain. These conditions and the resulting slick roads create noise for its vehicles’ sensors and can also result in other drivers behaving differently.

“Testing allows us to understand driving conditions and get a better handle on how rain affects our own vehicle movements too,” the company said in a blog post. “Both human-driven and self-driving cars need to drive in many different weather conditions.”

It has been more than six months since Waymo launched Waymo One, its commercial driverless taxi fleet of over 600 cars with safety drivers behind the wheel and the company says the fleet has grown to serve 1,000 riders in that time. Separately, Waymo recently revealed its cars have driven 10bn autonomous miles in simulation and 10m real-world autonomous miles in 25 cities.

Weeks after Waymo announced it would dedicate a factory in southeast Michigan to the production of level 4 autonomous cars — that is cars capable of driving without human supervision in most conditions — the company said it had settled on a location in Detroit. Separately, Waymo partnered with Lyft to deploy 10 of its vehicles on the ride-hailing platform in Phoenix.

Waymo currently operates a roughly 20-person, 53,000-sq ft office in Novi, Michigan which opened in 2016, and in Detroit, it tests driverless Chrysler Pacifica hybrid minivans produced in Windsor, Canada and shipped to Novi, where they are outfitted with hardware and software by Waymo and Chrysler engineers.

In Chandler, Arizona, Waymo last year expanded its full service centre — which houses operations and support teams, including fleet technicians, dispatch, response, and rider support — to 60,000 sq ft. More recently, the company pledged to open an 85,000-sq ft technical service centre in the city of Mesa, Arizona, near Phoenix’s East Valley, and it expects to “more than double” its capacity to maintain the fleet of cars in Waymo One.

Waymo also announced last year it would add up to 62,000 minivans to its fleet and said it had signed a deal with Jaguar Land Rover to equip 20,000 of the automaker’s Jaguar I-Pace electric SUVs with its autonomous system by 2020.

According to marketing firm, ABI, as many as 8m driverless cars will be added to the road in 2025 and Research and Markets anticipates there will be some 20m autonomous cars in operation in the US by 2030.