Laminar Research has formally announced X-Plane 12 at FlightSimExpo 2021 in San Diego, with the team highlighting various aspects of the simulator that have been overhauled and improved.
Weather
The weather system in X-Plane 12 is completely overhauled, with the new version switching to the National Oceanic and Atmospheric Administration (NOAA) GRIB (GRIded Binary) model to forecast weather. The GRIB model splits earth into a grid containing weather information and provides accurate weather forecasts based on complex algorithms.
X-Plane 11 uses METAR data to match real-world conditions. Although it provides accurate weather at airports, the disadvantage of using this method is it only covers the immediate area around airports and can cause large shifts in X-Plane weather in rapidly changing conditions.