The really good covers are the motorcycle ones, and those tend to run into gasp-choke territory pretty fast.

Tarps are a tie-down problem, and if you can't add ground anchors I would not expect it to work through the second windstorm. (Since the tarp has to go over the locks.) And even if it does work, if Facilities is already grumpy I expect that will be seen as an excuse to cause difficulties.

I would be entirely delighted to have a useful solution for this problem. I can come up with a bike-storage device, where you load up a carousel, but even there there's a spectral voice talking about recumbents. But simple, secure, proof-against-elements, on-street parking is hard.