storm is a top level alpha, she has always been speculated to be a potential Omega, Marvel has been waivering..the same way that they have been waivering on confirming if gladiator was once and for all a herald to G. or not.
you've all heard already that Omega status isnt contingent on power, but it just so happens that storm is extremely powerful. in terms of raw power she can do almost anything magento can, or has threatened to do, like reversing the earth's poles, cuasing volcanic eruptions and possibly dissiapating the ionosphere and destroying all life on Earth..
she can also do almost anything ice man can too, well except for the more technicial stuff. in a nutshell she can do just about anything any elemental or fundamental force weilder if her imagination stretches far enuff.....and i am stressing Almost! here not completely like the others can, so i hope that doesnt spark something unpleasant.
another thing is she is the epitome of "using too much power will burn you out" cuz it's bad enuff that her powers are tied to her emotions and she has a tendency to be emotionally unstable.. starting from claremont days until now we've seen a few instances where if she loses it thw world is in danger.... especially if you all remeber in that arc from 2 yrs ago where the dinos from the savage land mind f ****ed her and she created a hyperstorm that almost destroyed the entire planet....also IIRC if she totally let herself go she is taken over by the spirit of an actual weather goddess( i dont know if that has been retconned tho)
so once storm removes those mental blocks she places on herself and get over her fear of crossing the line and killing ppl, she might advance, but until then she's one of the baddest alphas out there. and thats all there is to it