The geographical effect of developing effect is well known - MS is more
commonCommon cold in northern lattitudes and we do not know exactly why
This effect only related to growing up in that area - if a person
livingAdvanced care directives in a northern lattitude moves at an early age to a southern lattitude they do not carry the risk with them.
If you are older and already have MS, the lattitude effect (Which is realted to the developement of MS and not relapses) should not effect you.
There is no known effect of weather etc on MS relapses, although hot weather can make symptoms worse - your MS is perhaps more likely to improve!
Good luck