Prognostic Discussion for Long-Lead Hawaiian Outlooks NWS Climate Prediction Center College Park MD 830AM EST Thu Nov 17 2022 MONTHLY FORECAST DISCUSSION VALID DECEMBER 2022 Sea surface temperature (SST) anomalies from positive one-half to one degree Celsius were observed over the Hawaiian islands (Kauai, Oahu, Maui and the Big Island) during the previous week. For January through October 2022, rainfall total accumulations were: - Lihue Airport 20.71 inches (75 percent of normal) - Honolulu Airport 9.76 inches (81 percent of normal) - Kahului Airport 1.62 inches (14 percent of normal) - Hilo Airport 70.01 inches (75 percent of normal) The NCEP Climate Forecast System (CFS) and other climate models of the North American Multi-Model Ensemble (NMME) predict above average SSTs around the Hawaiian Islands through December 2022. This supports likely above normal temperatures over the Hawaiian Islands in December 2022. Above normal precipitation is favored slightly for the Hawaiian Islands in December 2022, supported by most dynamical and statistical models. TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV Hilo A50 72.5 0.4 A40 6.8 10.2 13.6 Kahului A50 73.5 0.5 A40 1.9 2.7 3.4 Honolulu A50 74.9 0.6 A40 0.8 1.3 3.8 Lihue A50 73.3 0.5 A40 1.8 3.2 5.5 SEASONAL FORECAST DISCUSSION VALID DJF 2022 - DJF 2023 Refer to the prognostic discussion of the long-lead seasonal outlooks for the CONUS and Alaska for a description of the ENSO outlook and other climate conditions relevant to the seasonal outlook. La Niña conditions continue across the Pacific Ocean, with below average sea surface temperatures (SSTs) across the central and eastern equatorial Pacific Ocean. Predominantly negative subsurface temperature anomalies persisted at depth in the eastern Pacific and near the surface in the central Pacific Ocean, while positive subsurface temperature anomalies persisted at depth in the western and central Pacific Ocean. In the monthly average, low-level easterly wind anomalies and upper-level westerly wind anomalies were present across most of the equatorial Pacific, while sub-seasonal variability weakened low-level easterly trade winds. Convection remained suppressed over the western and central tropical Pacific and enhanced over the Maritime Continent. The tropical Pacific atmosphere and ocean remain consistent overall with La Niña conditions. La Niña is favored to continue through the coming winter (December-February) 2022-23 with a 76% chance, with a 57% chance of transition to ENSO-neutral conditions in February-April 2023. Enhanced probabilities for above normal temperatures are forecast for the Hawaiian Islands from DJF 2022-23 through MJJ 2023, consistent with most dynamical model forecasts from the NMME. The forecast signal weakens at longer leads, therefore Equal Chances (EC) for above, near or below normal temperatures are indicated for Hawaii beginning in JJA 2023 and extending through longer leads. Enhanced probabilities for above normal precipitation are forecast over Hawaii from winter (DJF) 2022-23 to AMJ 2023, consistent with most dynamical and statistical model forecasts. Due to considerable uncertainty in the precipitation forecasts from dynamical and statistical models over the Hawaiian Islands beginning in MJJ 2023 through longer leads, equal chances (EC) for above, near or below normal precipitation are indicated. Hilo TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2023 A60 72.8 0.4 A60 19.6 30.2 33.3 JFM 2023 A55 71.8 0.4 A60 22.0 32.0 44.5 FMA 2023 A50 71.7 0.4 A50 24.6 34.1 45.5 MAM 2023 A45 72.0 0.5 A45 22.5 28.4 34.0 AMJ 2023 A40 72.9 0.5 A40 21.4 23.7 29.0 MJJ 2023 A40 74.0 0.4 EC 20.2 27.5 29.1 JJA 2023 EC 75.2 0.4 EC 19.4 27.2 31.4 JAS 2023 EC 76.1 0.4 EC 25.2 28.6 33.4 ASO 2023 EC 76.4 0.4 EC 26.1 28.8 33.3 SON 2023 EC 76.2 0.4 EC 24.3 30.2 40.8 OND 2023 EC 75.5 0.4 EC 28.3 34.5 42.0 NDJ 2023 EC 74.2 0.4 EC 26.4 36.6 43.0 DJF 2024 EC 72.8 0.4 EC 19.6 30.2 33.3 Kahului TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2023 A60 73.8 0.4 A60 4.6 6.9 8.7 JFM 2023 A55 72.5 0.4 A60 4.2 6.2 8.2 FMA 2023 A50 72.3 0.4 A50 3.2 4.1 6.4 MAM 2023 A45 73.0 0.4 A45 2.5 3.5 4.6 AMJ 2023 A40 74.3 0.5 A40 1.2 1.6 2.2 MJJ 2023 A40 76.0 0.5 EC 0.7 1.1 1.8 JJA 2023 EC 77.7 0.4 EC 0.7 1.1 1.5 JAS 2023 EC 79.0 0.4 EC 0.8 1.1 1.6 ASO 2023 EC 79.4 0.4 EC 0.8 1.6 2.5 SON 2023 EC 79.1 0.4 EC 2.1 3.3 4.8 OND 2023 EC 77.8 0.4 EC 4.2 5.3 8.1 NDJ 2023 EC 75.9 0.4 EC 5.2 7.6 9.5 DJF 2024 EC 73.8 0.4 EC 4.6 6.9 8.7 Honolulu TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2023 A60 75.3 0.5 A60 3.7 5.6 8.6 JFM 2023 A60 73.9 0.4 A60 2.1 4.6 7.8 FMA 2023 A55 73.8 0.4 A50 1.9 3.2 4.7 MAM 2023 A45 74.8 0.4 A45 1.8 2.6 3.0 AMJ 2023 A40 76.3 0.4 A40 1.2 1.6 1.8 MJJ 2023 A40 78.2 0.4 EC 0.8 1.4 1.6 JJA 2023 EC 79.9 0.4 EC 0.7 0.8 1.3 JAS 2023 EC 81.3 0.4 EC 1.0 1.4 1.7 ASO 2023 EC 81.7 0.4 EC 1.6 2.4 3.1 SON 2023 EC 81.4 0.4 EC 2.5 4.0 5.6 OND 2023 EC 80.0 0.4 EC 4.4 6.4 8.5 NDJ 2023 EC 77.7 0.5 EC 3.9 5.6 8.8 DJF 2024 EC 75.3 0.5 EC 3.7 5.6 8.6 Lihue TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2023 A60 73.6 0.4 A60 7.5 8.4 14.0 JFM 2023 A60 72.2 0.4 A60 6.5 8.8 13.8 FMA 2023 A55 72.1 0.5 A50 5.8 8.4 9.9 MAM 2023 A45 72.8 0.5 A45 5.3 6.6 8.0 AMJ 2023 A40 74.2 0.5 A40 4.7 5.5 6.0 MJJ 2023 A40 76.0 0.5 EC 4.9 5.4 5.9 JJA 2023 EC 77.7 0.4 EC 4.4 5.3 6.9 JAS 2023 EC 79.0 0.3 EC 5.3 6.1 7.8 ASO 2023 EC 79.4 0.3 EC 6.2 7.9 8.4 SON 2023 EC 79.1 0.3 EC 9.2 10.0 11.2 OND 2023 EC 77.8 0.3 EC 9.2 11.7 15.6 NDJ 2023 EC 75.7 0.3 EC 8.6 12.1 16.9 DJF 2024 EC 73.6 0.4 EC 7.5 8.4 14.0 FORECASTER: Dan Collins Anomalies are based on the 1991-2020 means. CLARIFICATION: EC indicated equal chances that the predicted parameter will fall into any one of the three categories, whose boundaries are specific in the tables above. A forecast specification of EC means there is no particulate tilt of the odds toward above normal or below normal conditions in the outlook. For example A40 means a 40% chance that the average temperature or total precipitation will be in the above normal class, B40 means a 40% chance that the average temperature or total precipitation will be in the below normal class, and N35 means a 35% probability that the average temperature or total precipitation will be in the near normal class. When EC is specified, all categories are equally likely. NOTE - These outlooks are intended for use prior to the start of the valid periods. Within any valid period, observations and shorter range forecasts should be consulted. Also, this set of outlooks will be superseded by the issuances of the new set net month, on Thu Dec 15, 2022. $$