A/C not blowing cold anymore

Had the A/C serviced about a month ago. I replaced the dryer and then had a shop vacuum and refill it. They said there were no leaks in the system. Was blowing ice cold until yesterday when i went to go get some brewski's, blew out slightly cooler than the 95 degrees it was outside. Compressor clutch is spinning. What else can i check? 4.0l '95 XJ

FWIW car sat for 10 days while i was on vaca, and i hosed off the engine yesterday to get some of the mud off it.​