The phrase "gradually transition to" is correct and usable in written English.
It can be used when describing a process of moving from one state or condition to another over time.
Example: "We plan to gradually transition to renewable energy sources over the next decade."
Alternatives: "slowly shift to" or "progressively move to".
To the north the traditions of the Southeast gradually transition to those of the Northeast Indians.
Thus, as societies get richer they gradually transition to faster (and more energy intensive) modes of transportation.
The most common topographic features are basin and range systems; these gradually transition to high intermontane plateaus in the north.
But next year expect a gradually transition to counter terrorism.
Today it supports a mixed constellation of both legacy and newer spacecraft that will gradually transition to an all-SBIRS configuration by the end of the decade.
Thunderbolt's most high profile supporter, Apple, is expected to gradually transition to a single connector, according to Karen Haslam, editor of Macworld UK. "In the long run there will be no need for Apple to support these multiple formats with individual ports - existing products can run through an adaptor," she said.
All the technical systems required to fly the space shuttle were then gradually transitioned to the renegades' system.
Fallon will now be under pressure to hang on to as many loyal Leno viewers as he can, while gradually transitioning to a younger crowd.
For MTV, this meant showing only music videos at first, which it got for free, before gradually transitioning to costlier original programming.
Due to the continuous decline in PV module costs and the discontinued support in the form of feed-in tariffs, the market is gradually transitioning to installations for the purpose of self-consumption.
Across the political spectrum, renewable energy is the environmental measure that could unite the community: 71% of voters say they would consider voting for a party that supported distributed small-scale solar and storage, and in the country seat of Indi, held by independent Cathy McGowan, 85% of residents are supportive of gradually transitioning to 100% renewable energy.
