Johnson, who is a strong-running back rower with an ability to also operate in the front row, made one appearance for Warrington in the 2018 season against current champions, Wigan Warriors.
The former England Academy International arrived at the Halliwell Jones Stadium for the start of the 2018 season on a four-year deal from Castleford Tigers.
The highly-rated Johnson has already played in the Championship on dual-registration with Rochdale in 2019, and will add fire and competition to Kieron Purtill’s pack.
Phil Finney, Performance Director of Widnes Vikings, says: “We are pleased to have secured Luis for our squad on a month’s loan. Luis arrives at the club highly thought of, and will bring further depth to our squad over the next few weeks. I’m looking forward to seeing Luis in a Widnes shirt.
“I would also personally like to thank Warrington Wolves on behalf of everyone at the Vikings for their support with this loan move.”