Weather Effects in CO2 + Methane Atmosphere Planet?

I'm currently in the midst of a trilogy of novels. The planet is a swamp world with $.87$ g's of gravity, no axial tilt, $15.12$ psi atmospheric pressure, and whose mass is $.92$ of Earth.

Atmospheric composition: $74\%$ $CO_2$, $20\%$ Methane, $5\%$ Nitrous Oxide, trace amounts of $O_2$ and other gasses.

High concentration of $CO_2$ creates a greenhouse effect and it helps local flora and fauna due to the world being just beyond the Goldilocks zone. Water is present but anoxic. Thermal vents expel $H_2$.

EDIT:

animals: carbon + methane + hydrogen peroxide = expel $O_2$

plants: $H_2 + O_2 + C$ = secretes hydrogen peroxide and expels methane

methanogen bacteria in water = creates methane

My question is: can there be earthlike weather such as rain, fog, mists, thunderstorms, lightning, tornadoes, etc.

What is possible and what is not?

posted over 6 years ago

JTriptych‭

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