PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD 830AM EDT THU MAY 18 2017 MONTHLY FORECAST DISCUSSION VALID JUNE 2017 SEA SURFACE TEMPERATURE (SST) ANOMALIES SURROUNDING THE HAWAIIAN ISLANDS ARE CURRENTLY FROM POSITIVE ONE-HALF DEGREE TO TWO DEGREES. FOR JANUARY 2017 THROUGH THE END OF APRIL 2017, RAINFALL TOTAL ACCUMULATIONS WERE: - LIHUE AIRPORT 13.12 INCHES (95 PERCENT OF NORMAL) - HONOLULU AIRPORT 13.13 INCHES (189 PERCENT OF NORMAL) - KAHULUI AIRPORT 14.39 INCHES (164 PERCENT OF NORMAL) - HILO AIRPORT 26.97 INCHES (62 PERCENT OF NORMAL) THE NCEP CLIMATE FORECAST SYSTEM (CFS) AND OTHER CLIMATE MODELS RUN AS A PART OF THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) PREDICT ABOVE NORMAL SSTS AROUND THE HAWAIIAN ISLANDS. THIS ELEVATES THE CHANCES OF ABOVE-NORMAL MONTHLY MEAN AIR TEMPERATURES FOR THE HAWAIIAN ISLANDS IN JUNE 2017. EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW MEDIAN PRECIPITATION ARE ALSO INDICATED BY MOST DYNAMICAL MODEL FORECASTS FOR HAWAII DURING JUNE 2017. TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV HILO A60 75.4 0.4 EC 5.3 6.3 8.7 KAHULUI A60 78.0 0.5 EC 0.1 0.1 0.2 HONOLULU A60 80.3 0.4 EC 0.1 0.2 0.3 LIHUE A60 78.1 0.4 EC 1.1 1.3 1.6 SEASONAL FORECAST DISCUSSION VALID JJA 2017 - JJA 2018 REFER TO THE PROGNOSTIC DISCUSSION ON LONG-LEAD SEASONAL OUTLOOKS FOR THE CONUS AND ALASKA, AND DISCUSSION OF THE FORECASTS OF EQUATORIAL PACIFIC SSTS, FOR THE GENERAL BACKGROUND FOR THE SEASONAL FORECAST, INCLUDING DETAILS ON THE CURRENT STATE OF THE ATMOSPHERE AND OCEAN. ENSO-NEUTRAL CONDITIONS CURRENTLY ARE PRESENT ACROSS THE EQUATORIAL PACIFIC OCEAN. EQUATORIAL SEA SURFACE TEMPERATURES (SSTS) WERE NEAR AVERAGE NEAR THE INTERNATIONAL DATE LINE, WHILE ABOVE AVERAGE SSTS WERE MEASURED ACROSS THE EASTERN PACIFIC OCEAN. POSITIVE SUBSURFACE TEMPERATURE ANOMALIES STRENGTHENED IN THE WESTERN AND CENTRAL PACIFIC OCEAN AND WEAKENED IN THE EASTERN PACIFIC. ATMOSPHERIC CONVECTION ANOMALIES WERE WEAK OVER THE CENTRAL TROPICAL PACIFIC AND MARITIME CONTINENT, WHILE THE LOWER-LEVEL AND UPPER-LEVEL WINDS WERE NEAR AVERAGE OVER MOST OF THE TROPICAL PACIFIC. ENSO-NEUTRAL CONDITIONS ARE FAVORED TO CONTINUE THROUGH AT LEAST THE NORTHERN HEMISPHERE SPRING 2017, WITH INCREASING CHANCES FOR EL NINO DEVELOPMENT BY LATE SUMMER AND FALL. ENHANCED PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE INDICATED FOR HAWAII FROM JJA 2017 TO OND 2017 DUE TO PREDICTED ANOMALOUSLY ABOVE-NORMAL SEA SURFACE TEMPERATURES ACROSS THE REGION, WHICH IS ALSO CONSISTENT WITH CPC'S STATISTICAL TOOL (CONSTRUCTED ANALOG). EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW NORMAL TEMPERATURES ARE ANTICIPATED AT ALL LOCATIONS FOR NDJ 2017 AND BEYOND. FOR JJA SEASON, THE NMME FAVORS ABOVE MEDIAN PRECIPITATION FOR HAWAII, WHILE THE CPC CONSTRUCTED ANALOG (CA) TOOL PREDICTS ABOVE MEDIAN PRECIPITATION FOR THE NORTHWESTERN ISLANDS AND BELOW MEDIAN PRECIPITATION FOR THE SOUTHEASTERN ISLANDS. HENCE ABOVE MEDIAN PREDICTION IS FORECAST FOR LIHUE AND HONOLULU, WHILE EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW NORMAL PRECIPITATION IS INDICATED AT HILO AND KAHULUI IN JJA 2017. THE CA ALSO FAVORS BELOW MEDIAN RAINFALL FOR THE INCOMING WINTER SEASON. MOST DYNAMICAL MODELS PREDICT A WARM EVENT (EL NINO) BY THE NORTHERN HEMISPHERE SUMMER. IF CORRECT, HISTORICAL EL NINO COMPOSITES FAVOR INCREASED ODDS FOR DRY CONDITIONS FOR HAWAII IN WINTER, WHICH IS CONSISTENT WITH THE FORECAST FROM THE CA TOOL. THERE IS HIGH UNCERTAINTY WITH THE PRECIPITATION FORECAST FOR THE REGION FROM JAS TO OND 2017, AND IN MAM 2018 AND BEYOND. HILO TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV JJA 2017 A70 75.2 0.4 EC 19.4 27.2 31.4 JAS 2017 A65 76.1 0.4 EC 25.2 28.6 33.4 ASO 2017 A60 76.4 0.4 EC 26.1 28.8 33.3 SON 2017 A55 76.2 0.4 EC 24.3 30.2 40.8 OND 2017 A45 75.5 0.4 EC 28.3 34.5 42.0 NDJ 2017 EC 74.2 0.4 B40 26.4 36.6 43.0 DJF 2018 EC 72.8 0.4 B40 19.6 30.2 33.3 JFM 2018 EC 71.8 0.4 B40 22.0 32.0 44.5 FMA 2018 EC 71.7 0.4 B40 24.6 34.1 45.5 MAM 2018 EC 72.0 0.5 EC 22.5 28.4 34.0 AMJ 2018 EC 72.9 0.5 EC 21.4 23.7 29.0 MJJ 2018 EC 74.0 0.4 EC 20.2 27.5 29.1 JJA 2018 EC 75.2 0.4 EC 19.4 27.2 31.4 \N KAHULUI TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV JJA 2017 A70 77.7 0.4 EC 0.7 1.1 1.5 JAS 2017 A65 79.0 0.4 EC 0.8 1.1 1.6 ASO 2017 A60 79.4 0.4 EC 0.8 1.6 2.5 SON 2017 A55 79.1 0.4 EC 2.1 3.3 4.8 OND 2017 A45 77.8 0.4 EC 4.2 5.3 8.1 NDJ 2017 EC 75.9 0.4 B40 5.2 7.6 9.5 DJF 2018 EC 73.8 0.4 B40 4.6 6.9 8.7 JFM 2018 EC 72.5 0.4 B40 4.2 6.2 8.2 FMA 2018 EC 72.3 0.4 B40 3.2 4.1 6.4 MAM 2018 EC 73.0 0.4 EC 2.5 3.5 4.6 AMJ 2018 EC 74.3 0.5 EC 1.2 1.6 2.2 MJJ 2018 EC 76.0 0.5 EC 0.7 1.1 1.8 JJA 2018 EC 77.7 0.4 EC 0.7 1.1 1.5 \N HONOLULU TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV JJA 2017 A70 79.9 0.4 A50 0.7 0.8 1.3 JAS 2017 A65 81.3 0.4 EC 1.0 1.4 1.7 ASO 2017 A60 81.7 0.4 EC 1.6 2.4 3.1 SON 2017 A55 81.4 0.4 EC 2.5 4.0 5.6 OND 2017 A45 80.0 0.4 EC 4.4 6.4 8.5 NDJ 2017 EC 77.7 0.5 B40 3.9 5.6 8.8 DJF 2018 EC 75.3 0.5 B40 3.7 5.6 8.6 JFM 2018 EC 73.9 0.4 B40 2.1 4.6 7.8 FMA 2018 EC 73.8 0.4 B40 1.9 3.2 4.7 MAM 2018 EC 74.8 0.4 EC 1.8 2.6 3.0 AMJ 2018 EC 76.3 0.4 EC 1.2 1.6 1.8 MJJ 2018 EC 78.2 0.4 EC 0.8 1.4 1.6 JJA 2018 EC 79.9 0.4 EC 0.7 0.8 1.3 \N LIHUE TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV JJA 2017 A70 77.7 0.4 A50 4.4 5.3 6.9 JAS 2017 A70 79.0 0.3 EC 5.3 6.1 7.8 ASO 2017 A65 79.4 0.3 EC 6.2 7.9 8.4 SON 2017 A60 79.1 0.3 EC 9.2 10.0 11.2 OND 2017 A50 77.8 0.3 EC 9.2 11.7 15.6 NDJ 2017 EC 75.7 0.3 B40 8.6 12.1 16.9 DJF 2018 EC 73.6 0.4 B40 7.5 8.4 14.0 JFM 2018 EC 72.2 0.4 B40 6.5 8.8 13.8 FMA 2018 EC 72.1 0.5 B40 5.8 8.4 9.9 MAM 2018 EC 72.8 0.5 EC 5.3 6.6 8.0 AMJ 2018 EC 74.2 0.5 EC 4.7 5.5 6.0 MJJ 2018 EC 76.0 0.5 EC 4.9 5.4 5.9 JJA 2018 EC 77.7 0.4 EC 4.4 5.3 6.9 \NFORECASTER: LUKE HE ANOMALIES BASED ON 1981-2010 MEANS CLARIFICATION: EC INDICATES EQUAL CHANCES THAT THE CLIMATE WILL FALL INTO ANY ONE OF THE THREE RANGES OR CATEGORIES WHOSE BOUNDARIES ARE SPECIFIED IN THE TABLES ABOVE. A FORECAST SPECIFICATION OF EC MEANS THERE IS NO PARTICULAR TILT OF THE ODDS TOWARD ABOVE-NORMAL OR BELOW-NORMAL CONDITIONS IN THE OUTLOOK. FOR EXAMPLE A40 MEANS A 40% CHANCE THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE ABOVE CLASS, B40 MEANS A 40% PROBABILITY THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE BELOW CLASS, AND N35 MEANS A 35% PROBABILITY THAT TEMPERATURE OR 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 THEIR VALID PERIODS. WITHIN ANY VALID PERIOD OBSERVATIONS AND SHORTER RANGE FORECASTS SHOULD BE CONSULTED. ALSO - THIS SET OF OUTLOOKS WILL BE SUPERSEDED BY THE ISSUANCE OF THE NEW SET NEXT MONTH ON THU JUN 15, 2017. $$