Before I delve deeper into this topic I want to start off by saying this is NOT meant to be a versus thread (who would win in a fight) but meant to go into the discussion of explaining the differences in how their powers operate.
Now, after reading the recent one-shot Power of Light it got me thinking about both their powers how are they the same and how do they differ. What distinguishes these two?
The first time on panel I believe it was explained the differences between their two powers was in Uncanny X-Men issue 147:
This indicated a limitation in Ororo's ability which is she has to work within the confines of the existing weather. She cannot create weather from nothing whereas Thor's powers allow him via magic to create/dispel weather even if the setting doesn't allow for said weather effects (aka he can create hurricanes in space).
Hickman would much later reveal that Ororo is an omega level weather manipulator meaning in this power class there is no measurable upper limit to her ability. People including myself have asked does this make her as A MUTANT a better weather controller than Thor. The answer here is no as again their abilities at their core work differently. Storm manipulates energy patterns resulting in weather while Thor creates weather (no manipulating of energies).
Up to this point it would seem their powers in regards to how they function indicated though they both controlled weather they did so differently. However two recent marvel issues has modified essentially how storm powers work modifying the understanding of their two abilities.
In the curse of Man-Thing Thor sought out Ororo's help to disperse worldwide fir-spores:
And most recently Thor again sought Ororo's help to create a sustainable atmosphere and sun source:
In the last instance I dont believe this was Ororo's mutant powers at work but her goddess power as she mentioned before helping the Skrulls that she can't create weather from nothing. Nevertheless, this latest reveal seems to update what what distinguishes their power at least on the level of godhood. Thor can create great storms but life sustaining weather/environments are something Ororo's godhead allows her to do.
What are your thoughts?