Noise when releasing clutch

I appear to have an intermittent noise from the clutch when I release it in 1st gear and move from being stationary. It almost sounds as if the clutch plate is grinding against something with a groan. It doesn't happen all the time but seems to occur most often during wet weather or immediately after we've had wet weather.

Any thoughts before I take it into the Mazda dealer?

I have a manual 2.2 diesel.

How many miles (or km's) on your CX-5? Do you have new car warranty? The "grinding" noise under any circumstances from clutch is not a good sign. If you have grinding/groaning noise while the clutch pedal is pressed that means you have a wear-our throw-out bearing. If you have grinding/groaning noise when you just release the clutch pedal that may mean you have wear-out clutch plate or something else. New car warranty normally doesn't wear-out clutch plate as it is a wear-out item like brake pads.

Yes, but its only got 15,000 miles on the clock so it can't be normal wear and tear.