Surface Solar Radiation Observations at Three Sites across the Columbia River Basin as Part of the Wind Forecasting Improvement Project (WFIP-2)

The second Wind Forecast Improvement Project’s (WFIP-2) major goal is to improve representation of atmospheric processes in numerical weather prediction (NWP) models for more accurate low level wind forecasts in complex terrain. This effort involves multiple U.S. agencies, industry, and universities with a large suite of instrumentation including vertical profiling wind radars (WPR), sodars, lidars, and additional measurements including shortwave and longwave radiation, sensible and latent heat for understanding the development of low-level winds. This suite of instrumentation was deployed across the Columbia River Basin from approximately October 2015 – March 2017 to capture meteorological regimes of this region throughout the year, e.g. frontal passages, mountain wakes, and marine pushes. The sum of the incoming and outgoing radiative components at the surface constitutes the net radiation or net absorbed energy available for the transport of sensible heat and water vapor into the atmosphere and storage of heat in the ground. This net radiation is the bulk of the energy available for atmospheric dynamic processes that influence the boundary layer height and low-level winds. In this presentation, surface radiation observations will be used to determine uncertainties (MBE, RMSE, MAE) in the forecast of these variables from the NOAA 13-km Rapid Refresh (RAP), 3-km High Resolution Rapid Refresh (HRRR), as well as a high resolution (750-m) nest across three sites. Errors in the model forecast will be investigated diurnally and seasonally and within identified meteorological regimes. The HRRR has been targeted for specific improvements in model physics such as scale-aware aspects of turbulence parameterizations (PBL + shallow cumulus scheme) and land-surface physics. This analysis will explore the improvements in the model physics on forecasts of surface radiation and clouds.