WRF-Chem is the Weather Research and Forecasting (WRF) model coupled with Chemistry. The model simulates the emission, transport, mixing, and chemical transformation of trace gases and aerosols simultaneously with the meteorology. The model is used for investigation of regional-scale air quality, field program analysis, and cloud-scale interactions between clouds and chemistry.

The development of WRF-Chem is a collaborative effort among the community. NOAA/ESRL scientists are the leaders and caretakers of the code. The Official WRF-Chem web page is located at the NOAA web site. Our model development is closely linked with both NOAA/ESRL and DOE/PNNL efforts. Description of PNNL WRF-Chem model development is located at the PNNL web site as well as the PNNL Aerosol Modeling Testbed.


October 2020: U.S.EPA NEI 2017 input data are now available for download. See TOOLS tab for more information.

June 2019: Bug Fix for WRFV3.9 and WRFV3.9.1 New TUV option. Please read Instructions document

Nov. 2018:  The new EPA_ANTHRO_EMIS tool allows users to create WRF-Chem compatible hourly anthropogenic emission input files from Sparse Matrix Operator Kernel (SMOKE) Modeling System netcdf output.  See TOOLS tab for more information. 


ACOM WRF-Chem Developments for the Community

MOZART trace gas chemistry with GOCART aerosol scheme


Users Guide

MOZART trace gas chemistry with MOSAIC aerosol scheme


Users Guide

MOZART-T1 trace gas chemistry with GOCART aerosol scheme (new in V4.0)


Users Guide

New TUV photolysis code (phot_opt = 4)
Requires an additional data file; See Instructions for bug fix for WRFV3.9 and WRFV3.9.1:


Additional Data File

Trajectories monitoring meteorology, chemistry, etc



Output of Integrated Reaction Rates (new in V4.0)
IRR can be analyzed with PERMM Analysis Tool:


PERMM Users Guide

Henry's Law Table (new in V4.0)


More Information



Go to TOOLS page for more information:

  • US EPA anthropogenic emissions
  • Global anthropogenic emissions
  • MEGAN biogenic emissions
  • FINN fire emissions
  • Interpolate global model output for WRF-Chem initial and boundary conditions


Please see the Best Practices 2015 Tutorial Presentation that includes example namelists for running with MOZCART and MOZART-MOSAIC.

Submit questions regarding the tools and developments from our group to the WRF-Chem Discussion Forum.
For all other requests we refer to the WRF Forum.


WRF-Chem/DART is being used for: (i) development of efficient satellite retrieval data assimilation methods (compact phase space retrievals); (ii) independent and joint assimilation of atmospheric composition and meteorological observations, and (iii) estimating/constraining emission with the state augmentation methods. WRF-Chem/DART is being applied to two field campaigns, FRAPPE and KORUS-AQ, for atmospheric composition forecasting and data assimilation research. WRF-Chem/DART is also being applied to the MarcoPolo - Panda project for regional air quality forecasting in China.


New users may register and download WRF-Chem at the WRF Model Download page. Raw model output is available upon request for research purposes.




ACOM | Atmospheric Chemistry Observations & Modeling