Tom Hamill

Image of Tom Hamill




Attribution and Predictability Assessments




(303) 497-3060


I am the federal lead for PSD's "Attribution and Predictability Assessments" team. Additionally, I perform, coordinate, and lead R&D to improve NOAA's probabilistic weather forecasts on time scales of days to several weeks. The probabilistic forecasts are based on ensembles of weather simulations using different initial conditions and methods for simulating imperfections in the forecast model. I also am involved in the "post-processing" of ensembles of forecasts, making corrections to the real-time forecasts based on discrepancies noted between past forecasts and observations or analyses. My team and I develop these research methods, demonstrate their suitability for operational use, and then work with colleagues in the National Weather Service to adapt them for daily use by forecasters and the public. We document our work in the form of peer-reviewed journal articles, presentations, white papers, book chapters, and so forth.

My CV and list of my journal articles can be found at /people/tom.hamill/cv.html . Many of our experimental forecast products based on our global ensemble reforecast data set can be found at /forecasts/reforecast2/

Research Interests

  • Ensemble prediction methods
  • Ensemble-based data assimilation
  • Statistical post-processing
  • Forecast verification


  • Ph.D., Atmospheric Science, Cornell University, 1997
  • M.S., Atmospheric Science, Penn State University, 1987
  • B.S., Atmospheric Science, Cornell University, 1985

Professional Activities

  • Member, Cornell University Department of Earth and Atmospheric Sciences review board
  • Team lead, NWS Next-generation Global Prediction Systems Project, Ensemble Development Team

Professional Memberships

  • American Meteorological Society

Honors and Awards

  • 2020 : National Weather Association Operational Achievement Group Award for National Blend of Models development
  • 2017 : American Meteorological Society fellow
  • 2001 : Presidential Early-Career Award for Scientists and Engineers
  • 2002 : American Meteorological Society Editor's Award for Monthly Weather Review.
  • 2008 : NOAA outstanding scientific paper award for 2006 BAMS article on reforecasting
  • 2013 : Department of Commerce Bronze Medal (with Jeff Whitaker) for development of ensemble Kalman filters.

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