Just set the *23* column to your parent AreaID in the Map.dbc and in the game_weather u should fill the *zone* column with a specific areaID of your zone which weather needs changes.
What is my parent Area ID?
All I have is my map which is 725 and my Mountain area from the AreaTable.dbc which is 108108.
I tried making an area called "Test" which I set the mountains to it's parent area then setting test to the column 23 in map.dbc. But now the whole world's zone is Test
And back to my other question, how do I get the vmaps/map files from my custom map to my server? Where do I get an extractor that I can modify to extract my custom patch?