Blows up is often used as an antonym for "blows down." It suggests an upward, explosive motion instead of a downward, destructive one. Whereas "blows down" can signify the collapse of a structure or the destruction of trees due to strong winds, "blows up" implies the creation of something new or the expansion of an existing structure. This can include explosions, constructions, inflatables, and many other things. In contrast to the negative connotations of "blows down," "blows up" is often associated with growth and progress, making it a more positive and optimistic counterpart to the former.