Add the name of the script to the end of line 53 , which I think should be the line starting "5 addMPEventhandler" , which is actually line 55 ..
Add your script to the end , and it should look something like this: (lets say the scripts name is "weather.sqf")
5 addMPEventHandler !"\"addMPEventHandler\"," !"weather.sqf"
If there is a path to your weather script, include that too.. like:
5 addMPEventHandler !"\"addMPEventHandler\"," !"Scripts\weather.sqf"
Hope that helps.