EXPERIMENTAL Zonal/Meridional Wind Anomaly Forecast EXPERIMENTAL Relative Humidity Anomaly Forecast Valid: May and June 2023 Executive summary: The wind and solar forecast for late spring into early summer prominently projects above normal sunlight for most of the U.S. except (surprisingly) California into the Great Basin and the Northeast Corridor Coast. The remainder of the U.S. can expect above normal sunlight intensity for MAY/JUN 2023. On average, the only zone with marginally stronger than normal wind speed risk is the Great Plains/SPP region. Methodology discussion: There were no changes in the methodology of the May/June 2023 wind/solar forecast techniques. However, a chance considered for next month’s forecast is projecting 1000 MB wind anomalies due to the slight elevation at this level versus current ground-level forecasts. Climate discussion: As mid-spring passes El Nino is in the forecast for mid-to-late 2023. There is uncertainty in the intensity of El Nino this year with dynamic models favoring a strong warm ENSO while statistical models are weaker. ENSO forecasts have diminished skill during MAR/APR/MAY therefore a confident projection likely waits until June. May/June 2023 wind forecast: The outlook for May 2023 zonal wind speed anomalies is above normal speeds in the SPP region (Fig. 1). The meridional wind speed anomalies are stronger than normal on the East Coast and Western Texas (Fig. 2). The outlook for May has stronger zonal wind anomalies in the Central U.S. and stronger meridional wind anomalies on the East Cast compared to the previous outlook (Fig. 3-4). Fig. 1-2: Experimental Climate Impact Company constructed analog forecast of zonal and meridional wind anomalies for the U.S. during May 2023. In June, the outlook features above normal zonal wind speeds across the Mid-Atlantic region and the Southeast States particularly Florida (Fig. 5). Unusual is above normal zonal wind speed anomalies in Florida during June. Zonal wind speeds across California, Texas, and SPP are generally near normal. Meridional wind speeds during June are below normal on the East Coast and above normal in the southern half of the SPP region (Fig. 6). Fig. 3-4: Experimental Climate Impact Company constructed analog forecast of zonal and meridional wind anomalies for the U.S. during June 2023. May/June 2023 solar forecast: The May 2023 solar outlook calls for above to much above normal sunlight across most of the West and Central U.S. (Fig. 7-8) with the exception of an occasional low cloud issue in California. SPP region is generally observing above normal sunlight during May. In the East, above normal high cloud is projected to dim sunlight intensity. The outlook features increased sunlight compared to the previous forecast (Fig. 9-10). Fig. 5-6: Experimental Climate Impact Company constructed analog forecast of 850 MB (low cloud) and 300 MB (high cloud) relative humidity anomalies for the U.S. during May 2023. Previous below. The sunlight outlook for June 2023 features above normal amount for all of the U.S. with two exceptions. The Great Basin and California are susceptible to low clouds to suppress sunlight intensity at times (Fig. 11). Low clouds also suppress potential sunlight in New England and the Mid-Atlantic region (Fig. 12). Fig. 7-8: Experimental Climate Impact Company constructed analog forecast of 850 MB (low cloud) and 300 MB (high cloud) relative humidity anomalies for the U.S. during June 2023.