The Final (FNL) global tropospheric analyses archived here were produced by NCEP's Global Forecast System (GFS), which was run operationally at 12-hour intervals to make multiple-day weather forecasts, from July 1976 through mid-April 1997. FNLs are analyses that are produced after the model has completed the forecast cycle, and they include the most complete set of observations available for a given cycle. The FNL from a given cycle, which is the best available analysis, is then used in the initialization of the next cycle.

FNL Data are available on pairs of 2.5-degree hemispheric grids (North and South) at the Earth's surface, twelve vertical levels from 1000 millibars up to 50 millibars, the tropopause, boundary and some sigma layers, and a few other levels. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, potential temperature, relative humidity, snow depth (weekly, Northern Hemisphere only) precipitable water, u- and v- winds, and vertical motion.