While Scotland rounded off their international series with victory over Tonga, there were contrasting fortunes for Gregor Townsend's side as they slipped to only their second defeat of the season away to Scarlets on Friday.
Alongside the return of their international stars, Weir admits Glasgow will be boosted by playing four of their next five games in all competitions under the Scotstoun lights, starting with Newport Gwent Dragons on Sunday.
And with Weir battling teammate Finn Russell for the No. 10 jersey for both club and country, the 23-year-old admits he needs to grab every opportunity during a busy schedule of domestic and European action.
"We had a disappointing result on Friday but I'm excited to come back to a good atmosphere like the one we've built with Scotland," Weir told the Glasgow Evening Times.
"I'm glad to be back among the boys here. We've got a big couple of weeks ahead of us. I'm desperate to go forward and grasp every minute I can get at Glasgow.
"We have a huge run of games coming up and, with four at home, it will be the key to our league and European success. It's a great challenge and, as a player, you need to respond positively to the opportunities that come your way.
"When you walk back through the door your mind is completely on Glasgow. Throughout the month away we were still popping in on our days off to see the boys, or even coming in for a stretch or a massage.
"It's all about driving Glasgow forward. We all understand that Friday wasn't good enough and we didn't meet our standards. We have to draw the line there and look forward and keep driving upwards."
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