The J-SCOPE forecast system for Washington and Oregon coastal waters presents preliminary results for the 2021 upwelling season. The CFS forecasts a transition from La Nina (ENSO-negative) to ENSO-neutral conditions for the Northern Hemisphere summer 2021 (80% chance). In comparison to the climatological data, during the summer upwelling season (May - August), WA and OR shelves sea surface temperatures (SST) are forecast to be near climatological, with cool anomalies forecast for subsurface bottom waters and developing in the fall/winter. Bottom oxygen is forecast to be lower than normal in the Washington and Oregon shelf waters over the upwelling season and throughout the fall. Chlorophyll concentrations vary spatially but are forecast to be near climatology on the Washington shelf, except for near the Columbia River plume, and higher than climatology on the Oregon shelf, during the upwelling season. Bottom Ω is forecast to be undersaturated throughout the upwelling season, with the exception of supersaturated conditions in shallow coastal regions of Washington early in the upwelling season. Surface Ω is forecast to be supersaturated throughout the upwelling season for all coastal areas.

The forecast system predicts the timing of the spring transition from downwelling to upwelling, the cumulative upwelling index, sea-surface temperature (SST), primary production, chlorophyll stock, dissolved oxygen, and sardine habitat. The forecast for 2021 is composed of three model runs that make up an ensemble. Each model run is initialized at a different time (April 5, April 15, April 25), and has complementary forcing files from the large scale model, CFS. The details of the wind forcing for each model run can be found on the California Current Indicators tab. For each of the predicted quantities listed above, we report the ensemble average anomaly as well as the relative uncertainty within the ensemble, which is defined as the standard deviation of the ensemble divided by the mean of the ensemble and is reported as a percentage of the mean. All of these quantities are reported as monthly averaged anomalies from our April-initialized reforecast climatology, which spans 2009 - 2017. An anomaly is an indication of how different conditions are to what they have been in the past. For more information about anomalies, please see the NANOOS Climatology App. These predicted quantities are key indicators for the California Current Integrated Ecosystem Assessment report.