An Andy Little strike just before half-time handed the Light Blues a narrow 1-0 victory in Sunday's Scottish League One clash, although the display left a lot to be desired.
Station Park is one of several grounds in the lower divisions with a plastic pitch. McCoist has made his feelings about the surfaces known in the past but did not feel it was the overriding factor on this occasion.
McCoist said: "I'm not going to have a moan about the surface because we have to get on with it.
"A few players went down because of it and Arnold Peralta twisted his studs on it.
"But you have to play on it so there's no point complaining about it."
However, McCoist did feel the blustery conditions played a big part in restricting his players from performing as well as they could have done, as dissenting travelling fans made their feelings known.
He said: "I wasn't happy with the performance and I agree with the fans.
"We told the players that but I can sympathise with the players because of the wind.
"As disappointed as we all are with the performance, I would certainly cut the players some slack because of it.
"The conditions played a massive part in the way the game was played and sadly for the fans there wasn't a lot of good football."
He added: "The wind was horrendous and all over the place.
"You saw the amount of times the ball either hung up or went flying forward.
"It didn't help the flow of the game and didn't help either of us pass the ball.
"When you have conditions like that you have to adapt to them. Both teams attempted to do that as best they could.
"I thought we had the better chances but Forfar still had a threat, particularly late in the second half."
Forfar assistant boss Ian Campbell said: "The goal we lost wasn't acceptable, not at any level of football.
"But I thought we played well and we are disappointed not to take something from the game. Our finishing and set-pieces were not good enough.
"I don't think Rangers created a lot of chances and we coped with them pretty well.
"But we didn't put the ball in the net when the chances came along for us.
"We worked hard and were organised and we will take a lot out of the game. Hopefully we can take this on now to the rest of the league."