How does Killer Frost drain the atmospheric pressure of Jupiter suddenly crushing her brain from the inside?
Or the neuroelectrical signals of her brain being scrambled?
At best, this is a quickdraw between the two, but the difference is Storm has fought another Omega-level mutant - Iceman, who is more powerful than KF, and easily held her own, not to mention actually has more resistance to being frozen than KF has resistances to all the esoteric atmospheric shenanigans Storm can pull off.