You really have 3 dedicated circuits that serve nothing but 1 outdoor receptacle each?  That would indicate you have the coolest electrician ever!   I think in reality, you would find that turning off those 3 breakers will shut off power to other parts of your house.   

If that is the case, shutting them off may not be an option. The next step is finding if those indoor outlets** are upstream of the outdoor GFCI.   If so, see if you can move the GFCI to the indoor upstream location, feed the rest of the circuit off the LOAD terminals, and now you don't have to worry about valuable GFCIs getting rained on.   

Otherwise you may not have a choice, unless you are able to bypass the outdoor receptacles so they are on a branch of the circuit.  



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** "outlet" is the word for any point-of-use, including both receptacles and any hard-wired loads like lights (including their switches), gas furnace, gas water heater, etc.