This one will not be easy to change but it is easy enough to understand. Hopefully is an adverb, a word that modifies a verb (an action word). Thus, a correct usage would be: “Hopefully, he rose to address the assembly.” In this case hopefully describes the spirit in which the person rose to speak. The most frequent usage, however, is incorrect: “Hopefully it will not rain tomorrow.” The weather is not hopeful. The weather doesn’t have feelings of anticipation or expectation. The weather just is. What people usually mean when they say “Hopefully x will happen” is, “I hope that it will not snow tomorrow.” I’m not entirely certain why we have become reluctant to say “I hope x does not happen.” Perhaps it is part of general pattern of relativizing truth claims? We see this in constructions such as “I feel that…” or “In my opinion…” or “I think that…” On the surface these seem innocuous enough but the effect of such qualifiers is communicate the notion that “this is what I think but I’m not saying that it’s true for everyone.” Consider the difference between “It is cold outside” and “It seems to me to be cold outside.” In the first instance there is an unequivocal claim about what is the case. In the second, there is a claim about what is subjectively experienced.
In any event if you want to describe the hopeful attitude with which something is being done, then use hopefully. If, however, you mean say what you hope might be the case, then say it directly. This distinction works for other adverbs such as thankfully. “I am thankful that…” means one thing. “Thankfully, he received the donation to the Heidelblog” means something else.