|MadSci Network: Earth Sciences|
You can probably make a fairly good forecast without any personal equipment using observations and forecast information on the web. A general knowledge of how weather systems work is all that's necessary to get you started. You might begin with USATODAY's page on understanding weather forecasts. Follow the links to many other sites that can be helpful. The National Weather Service and Environment Canada have observations and forecasts on-line, as do USATODAY, WSI Corporation and other non-government sites. Look around and find one that suits your needs.
The National Collegiate Forecasting Contest has a tutorial to help you make a forecast. Good luck.
Try the links in the MadSci Library for more information on Earth Sciences.