GFSv16.0.9

GFS version 16.0 is the first major upgrade to Finite Volume Cubed Sphere (FV3) dynamical core based GFS which replaced the spectral dynamical core in June 2019. In this upgrade, the number of model vertical layers is increased from 64 to 127 and the model top is extended from the upper stratosphere (~55 km height) to the mesopause (~80 km height). With this upgrade, for the first time, the operational stand alone global deterministic WAVEWATCH III based wave model Multi_1 (wave_multi_1.v3.3) is merged into the GFS system. The WAVEWATCH III model is updated and coupled to the GFS using a one-way coupling scheme where the atmospheric model provides forcing to the wave model using the NOAA Environmental Modeling System (NEMS). Major changes have also been made in other components of the forecast system including model physics, data assimilation, system infrastructure, post-processing and product generation.

Merged final GFSv16 (v16.0.9) package into operations branch. GFSv16.0.7 system implemented March 22nd 2021 @ 12z. Follow-up updates/fixes resulting in v16.0.8 (~March 31st) and v16.0.9 (April 27th 12z) were implemented.