This is a very exciting prelude, and I think it displays well your growing prowess in meandering through neighboring tonalities. In particular, I enjoyed those cadential dim7 chords at m.3, for instance... made the piece sound extra 'stormy.'
There were a couple of places that lacked a convincing cadence, though, at least to my ears. At m.9, that descending run through a C harmonic minor scale atop a block C minor chord was too musically abrupt. While this may have been intentional to add to the character of the piece, it came across, to me, as a mistake. You could probably continue the stepwise pattern down from the previous measure (which ends in a tremoloed G in the bass) to F then Eb then D, and this will, I think, provide a better cadential feel than the immediate switch back to the tonic. (You'll need to adjust your notes in the treble clef, too, of course.)
Measures 13-20 proceeded too quickly through various tonalities for my tastes. I would suggest either doubling the amount of time spent in each tonality (Eb in m. 14, for instance) or getting rid of some of those chord progressions altogether. Nothing about this section felt 'wrong,' however. It just seemed to be a quick departure into major tonalities for the sake of departing into major tonalities.
Overall, though, you've done a great job here. I look forward to hearing more of your stuff!