Change WPS and/or WRF settings so that initial conditions have hydrometeors

The current settings of WPS/WRF are such that the initial state of the model (initial wrfout files) has no hydrometeors. This greatly affects the initial forecast moisture fields, and results in unrealistic precipitation forecasts for the first several hours of the simulation (long spin-up time). This seems especially bad for a tropical setting.

Describe the Enhancement

Modify the WPS or WRF settings (or both) in order to include hydrometeors in the initial conditions.

This may be as simple as modifying the VTABLE, per this wrfhelp forum post: https://forum.mmm.ucar.edu/threads/resolved-using-hydrometeor-mixing-ratios-in-gfs-metgrid-error-in-ext_pkg_write_field.8644/

There is literature that indicates this significantly reduces spin-up time (improves short-term forecasts): https://ui.adsabs.harvard.edu/abs/2020AGUFMA183.0007L/abstract

Time Estimate

1 day

Sub-Issues

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Relevant Deadlines

NONE

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Start by locating the repository's WPS and WRF configuration and any VTABLE used to generate the initial wrfout files. Reproduce the current initialization, inspect the hydrometeor fields, and compare the result after changing the settings. Done means the initial conditions include hydrometeors and the first forecast hours show reduced moisture spin-up.