Experimental Probabilistic LIM Subseasonal Linear Inverse Model (LIM) forecasts (Weeks 1-6): Background

Experimental forecasts for: North American 2m temperature and soil moisture; Northern Hemisphere mean sea level pressure (SLP), 500 mb geopotential heights, 750 mb and 100 mb stream function; and tropical sea surface temperature and column integrated irradiance (tropical heating). The LIM is trained on Japanese Reanalysis Three Quarters of a Century Reanalysis (JRA-3Q) between 1958-2016, where anomalies are computed using a 20-year sliding mean (e.g., the year 2016 is centered using a 1996-2015 climatology period). In addition, 2m temperature is also given as an anomaly re-centered on the current operational NOAA Climate Prediction Center 30-year ‘climate normal’ period (1991-2020).

For documentation on the creation of a subseasonal LIM, see Albers et al. 2022.

Albers, J. R., M. Newman, A. Hoell, M. L. Breeden, Y. Wang and J. Lou (December 2022): The February 2021 Cold Air Outbreak in the United States: a Subseasonal Forecast of Opportunity. Bull. Amer. Meteor. Soc., 103 (12), E2887–E2904, (https://doi.org/10.1175/BAMS-D-21-0266.1).

Data Source: Documentation and references for the the JRA-3Q reanalysis can be found at this Japanese Meteorological Agency (JMA) web-page.

For web-page issues, contact psl.data@noaa.gov. For additional information regarding the forecast generation, contact Dr. John Albers (john.albers@noaa.gov),

This is a Research and Development Application