Although the metaphor of stormchasing and bipolar "storms" was apt, the relentless reminder to the reader of how Charles' illness affected his sister, was overdone. I think most readers will be able to predict the outcome of the story once the "secret" is revealed. I did, however, enjoy the technical information about the development and science of storms, particularly tornadoes, since I live in the Midwest where this type of weather is common and often destructive.
Another reviewer has remarked about the fact that the two men in the book rarely use Karena's name. Her brother (and twin) calls her either "K" or "sistah", and her boyfriend refers to her as "Laredo" or some other term. I also found that annoying. I really never felt that I got involved with the characters in this novel -- they were very one dimensional and I found myself becoming irritated at times rather than empathizing with their plight. I was basically just glad to get to the wholly anticlimactic end.
I will wait patiently for Blum's next novel, and see if she can revert to the quality storytelling that made me a fan when I read her first book. Overall, just found The Stormchasers only mildly interesting, a bit disappointing, and would tell those who ask, "It's OK."