Harold said he often wore a cap and a Holden T-shirt and had scraggly hair to below his ears.
"When he comes in, he often asks for membership forms to the squash, tennis or bowling club, as if he is a prospective member. He will wander anywhere in the club that he can get to, which includes the ladies' changing rooms, to look for things."
Harold warned members to try to make it harder for the intruder to do so.
"The dog he has with him is a small black one, often with a harness on it, and he either brings it into the club or ties it up to one of the poles outside. It is not the type of dog you would expect to see with such a dodgy guy - it's quite cute and pretty.
"If you see him around town with his dog, or at the club, even outside, contact the police and let them know, or contact the club," Harold said.
Warning to members
Please do NOT hook the front door back when you are playing your games, squash or tennis.
Please make sure that you lock the front door on your way out and have your access card ready when you come so that you can get in.
Please be aware of who is in and around the club and facilities.
When you play your game please use the boxes on the courts or the office (if Pip is in there) to store any valuables that you have.
If you open the lounge and bar upstairs it is your responsibility to close it, & alarm it or pass the responsibility on to someone else that has a pin & can lock up when they leave.