GeoPoint: A latitude/longitude pair defining a location on the globe. You might not have heard of this before, because I made it up. 🙂

GFS: The Global Forecast System (GFS) is a model used by meteorologists to forecast future conditions worldwide.

GRIB(2): The GRIdded Binary format often used to store meteorological data. The format standard is managed by the World Meteorological Organization.

NWS: Short for National Weather Service, the primary government weather organization for the United States.