Should I refinance my mortgage now or wait until my ARM expires?

I'm two years into a 5 year ARM with an interest rate of 4.375%. I'm worried that interest rates will just keep climbing and that I'll suffer for it in the long run if I don't refinance. I do have a 2% cap per year after the fifth year. The rate could get to above 11% total if I don't refinance. However, I just cringe at the thought of refinancing at a HIGHER rate, even though it may be better in the long run.