  We describe two recent additions to WRF coupled with a fire spread model.
Fire propagation is strongly dependent on fuel moisture, which in turn depends
on the history of the atmosphere. We have implemented a equilibrium time-lag
model of fuel moisture driven by WRF variables. The code allows the user to
specify fuel parameters, with the defaults calibrated to the Canadian fire
danger rating system for 10-hour fuel. The moisture model can run coupled with
the atmosphere-fire model, or offline from WRF output to equilibrate the
moisture over a period of time and to provide initial moisture conditions for a
coupled atmosphere-fire-moisture simulation. The fire model also inserts smoke
tracers into WRF-Chem to model the transport of fire emissions. The coupled
model is available from OpenWFM.org. An earlier version of the fire model
coupled with atmosphere is a part of WRF release.
