So we are level at 7000' on a right downwind with another airplane on a left downwind. We are number two to land with the field in sight (clear weather below 6500'). Ask ATC for lower since we are right at the bases of some cumulonimbus summer pop ups. He says he can't give lower due to ifr terrain off our left side which we see. Can you cancel IFR at this point and descend to avoid the bottoms of the clouds?

Thanks for any tips.