Research: Pokémon Emerald Weather Hacking

Hello!
I am working on a semi-custom ROM Hack for Pokémon Emerald, and I want to change the palette for the sandstorm particles to make it look like a blizzard, and to change text offsets to display 'A blizzard is raging/hail continues to fall'.

So what I am to achieve is:
1. To edit weather palettes without breaking the game (as last time I tried to did break the game, I got a white screen.)
2. Find weather information text offsets for editing.
3. Change default weather effects for a specific area.
4. Fix the unfinished weather effects and possibly replace them with something new.
and finally,
5. To edit the weather effects to affect the correct Pokémon.

If anyone wants to help out, that would be appreciated. I will upload information I have found when I get home.
Cheers.

Hello, so I have found the offsets of the weather effects sprite, and with the help of a previous weather-related thread, the palette too.

Here are the offsets:
Sprite/picture: 54dad0
Palette: 54c270 (credit to Artemis64)

The sprite appears to be uncompressed, which Artemis64's source backed up. I wish I found his information before looking for the sprite, I feel silly now!

These are standard for a regular, untrimmed Pokemon Emerald (BPEE) ROM. I still aim to find the offsets for weather effects, and will keep posted as part of my log.
Cheers

For anyone viewing this these days, as evident in the amount of views, there are some helpful resources out there. I did not mean to ghost you, I just lost interest in Pokemon!
An older weather development thread: https://www.pokecommunity.com/showthread.php?t=351387
A basic introduction into where to find weather values: https://www.youtube.com/watch?v=CPsYt5MhKxQ