You need to download a mod. I have found a mod pack with weather control and many other things. I have tested it, and it works fine. The link can be found under "Sources and related links" below this answer.
/toggledownfall to stop or make rain in minecraft
To make it rain/snow you type this wothout the quotes "weather/rain" to make it sunny type "weather/clear"
Minecraft has no rain forests, the current boimes, (as of 1.8) are:ForestTaigaSwamplandExtreme HillsDesertPlainsOcean
In the chat box type in; /weather clear to make it sunny, /weather rain to make it rain or /weather thunder to create a thunderstorm
If you have cheats turned on (which you do when you create your world), open the chat box with t and type /weather clear
I didn't make Minecraft.
You can only turn off the rain if cheats are enabled. If they are, the command is /toggledownfall
If you have enabled cheats in your world on the PC edition, the command to toggle rain on or off is /toggledownfall.
There are no keys in minecraft!
how to make a fire works in minecraft 1.5.2
you can't make a pencil in minecraft, but there mite be a mod for it.
You have to have a mod (modification) to make a cannon. It is not in vanilla minecraft.