Two things....what weather station(s) will you be using the data from ? Will you be compensating the owner of that station for using their data for your money making scheme? If it were mine I would want a "piece of the action" (STOS). My station is for providing my local climate information to others climate services and I don't want it's data used for someone to make a quick buck off of and I get nothing. However, I find the whole idea of betting on the weather silly.
Are you going to be issuing IRS form W2-G to your gamblers ? If not, well, you are asking for some big trouble. Also did you know that online gambling is illegal in... Alabama, Alaska, California, Idaho, Missouri, North Dakota, Oklahoma, South Carolina, South Dakota, Texas, Vermont ? You need to research your hustle a bit more. It doesn't sound like you have all your info. together.