Increased network load (Score 1)

In addition to all of the comments about weather actually affecting the data centers that "the cloud" resides in, bad weather pushes most people inside. Instead of being out of their house doing something else, people will start browsing the Internet, increasing the network and server load in these data centers. Large enough storms might drive up traffic just enough to cause, at minimum, a small spike in loads, and at worst would force load distributors to do their work.