Shes not a Omega class mutant right? but a strong alpha, yeah shes one of the more powerfull ones (amoung alpha's).

1) control weather (control winds / fly (breathe at any speed/height in the atmosphere))
2) create lightning bolts,  see patterns in the electrical energy (she has more than just normal vision)
3) adapt to enviroments so her powers work on other planets


She is limited in her power though, usually by area, shes not able to control all weather across the intire world at once, but more in a localised part of it.
Also the larger the area, the quicker she drains her power, she can spend so much energy she ll stop being able to do her stuff.

Powerfull X-men:

I always liked Ice-man (he becomes Omega class).

1) Creates ice by absorbing and dispelling heat.
2) able to turn his entire body into organic ice, gain super strength and size by absorbing water molecules around him, heal in ice form, and kill or paralyse by freezing the water in a human body.
3) With the help of Emma Frost, he has developed further powers, including the ability to change his body to a gas form, to travel by merging himself with water molecules, to shape shift, and to survive as sentient water vapor (making him essentially invincible).