Morley has been out since April with a neck injury and his anticipated return for last week's Challenge Cup tie against Catalan Dragons in Perpignan was put on hold after he picked up a back injury in training.
"He jarred his back in training late last week," said Warrington coach Tony Smith. "We were taking him to France but he had to pull him out. He thinks he'll be right but we'll give him a fitness test tomorrow."
Both utility back Ratchford, who damaged a shoulder in March, and back-row forward Solomona, who broke a leg during the club's pre-season training camp in Australia, have recovered fitness earlier than expected, with the former also set to play this weekend.
"Stefan is 100% and raring to go so I'm tempted to throw him in at the deep end," said Smith. "He's rehabbed ahead of schedule but he's been back to the consultant and had all the strength testing and he's ready to go.
"He's looking good. He's been in full training for a couple of weeks and is looking sharp. He's jumping out of his skin to play."
The 34-year-old Solomona was not expected to return until July but has been given the go-ahead to resume full training and Smith expects him to be back playing next month.
"The first reports were July but he worked really hard," he said. "He's a strong guy and he's healed well. He's done all the right things. He's a real positive person."
The former Wakefield and Bradford forward is among a host of Warrington players out of contract at the end of the season and is determined to win a new deal.
"He's off contract at the end of the year so in a short period of time he's going to try and prove some points," added Smith. "That's extra motivation for him. For him to come back and almost start his season is quite exciting for us. He's got some of the X factor that not a lot of people in the game have got."