A prediction game is a game which allow users to guess at the outcome of future events. Prediction games are generally operated online and are free for users to play. Points are awarded to players who most accurately predict the outcome of an event, and those points are converted into cash prizes.
US NCAR Climate and Global Dynamics Division
cgd.ucar.edu
The National Center for Atmospheric Research's division devoted to climate modelling. Provide newsletters and an overview of their research.
Clear Sky Clock homepage
cleardarksky.com
Weather predictions specifically for astronomers for hundreds of observatories, observing sites and clubs in the USA and Canada.
Climate Diagnostics Center
cdc.noaa.gov
The mission of CDC is to identify the nature and causes of climate variations on time scales ranging from a month to centuries.