The England international is recovering from surgery after an emergency appendectomy, which could see him miss the rest of the season.
Powell's men are one of the favourites to reach next month's Grand Final but they may need to do it without Gale.
He broke a club record for points in a season during last week's win over Leeds but Powell admits he is recovering well.
The former Featherstone Rovers coach believes it could be touch and go and he is adamant Gale will be given the decision on his participation.
He told reporters: "He's got his feet up at home recovering. He's had keyhole surgery so that's the best. If they'd have had to open him up, that would have been him done.
"I'm not sure how he's going to roll through the next couple of weeks. We'll just have to keep assessing him. He's coming in to watch the boys train on Saturday so I'll have a chat with him them.
"It's going to be up in the air right until just before the game I'd say. We've got to get a fair bit of evidence gathered in and we'll see how he goes.
"We'll take evidence from the doctor and see how Luke feels. Ultimately it will probably be down to him."