GSSF matches are usually well-run and can be a lot of fun (bad weather excepted, of course). You can also get your Glock checked-out by a Glock armorer, free of charge, at most GSSF matches; they will usually replace any worn parts for free, while you wait.
The one I went to about 12 years ago was in mid/late-summer, and it was hot enough that I thought I was gonna melt. I still shot well enough to finish "in the money" in all three divisions I entered, but not well enough to win a pistol. I was satisfied with my performance, considering the conditions. Heat/humidity like that are where frames with the Gen4, or Gen3 RTF2 gripping texture are a big plus.
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)