622  
FXHW40 KWBC 181231  
PMDHCO  
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD  
830AM EDT THU JUN 18 2026  
 
MONTHLY FORECAST DISCUSSION VALID JULY 2026  
 
SEA SURFACE TEMPERATURE (SST) ANOMALIES IN THE RANGE OF -0.5 TO -1.0 DEGREES  
CELSIUS (C) WERE OBSERVED AROUND THE HAWAIIAN ISLANDS (KAUAI, OAHU, MAUI AND  
THE BIG ISLAND) DURING THE PREVIOUS WEEK.  
 
FROM JANUARY THROUGH MAY 2026, RAINFALL TOTAL ACCUMULATIONS WERE:  
 
LIHUE AIRPORT 34.14 INCHES (210 PERCENT OF AVERAGE)  
HONOLULU AIRPORT 20.78 INCHES (269 PERCENT OF AVERAGE)  
KAHULUI AIRPORT 27.30 INCHES (300 PERCENT OF AVERAGE)  
HILO AIRPORT 64.72 INCHES (137 PERCENT OF AVERAGE)  
 
MOST CLIMATE MODELS OF THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) AND THE  
INTERNATIONAL MULTI-MODEL ENSEMBLE (IMME/C3S) PREDICT POSITIVE SST ANOMALIES  
AROUND THE HAWAIIAN ISLANDS IN JULY 2026. BASED ON MODEL SST AND SURFACE AIR  
TEMPERATURE FORECASTS, ABOVE NORMAL TEMPERATURES ARE FAVORED FOR KAUAI (LIHUE),  
OAHU (HONOLULU), MAUI (KAHULUI), AND THE BIG ISLAND (HILO).  
 
FOR THE JULY 2026 PRECIPITATION OUTLOOK, THE PROBABILITY OF ABOVE NORMAL  
PRECIPITATION IS ELEVATED FOR MAUI AND THE BIG ISLAND, WHILE BELOW NORMAL  
PRECIPITATION IS FORECAST FOR KAUAI AND EQUAL CHANCES (EC) FOR ABOVE, NEAR OR  
BELOW NORMAL PRECIPITATION IS INDICATED FOR OAHU. THE OUTLOOK IS SUPPORTED BY  
MOST OF THE DYNAMICAL MODEL PRECIPITATION FORECAST TOOLS.  
 
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
HILO A70 76.2 0.4 A50 7.1 9.5 11.4  
KAHULUI A70 79.2 0.4 A40 0.2 0.4 0.5  
HONOLULU A60 81.4 0.5 EC 0.2 0.4 0.5  
LIHUE A50 79.2 0.4 B40 1.5 1.7 1.9  
 
SEASONAL FORECAST DISCUSSION VALID JAS 2026 - JAS 2027  
 
REFER TO THE PROGNOSTIC DISCUSSION OF THE LONG-LEAD SEASONAL OUTLOOKS FOR THE  
CONTIGUOUS U.S. (CONUS) AND ALASKA FOR FURTHER DESCRIPTION OF THE EL NINO  
SOUTHERN OSCILLATION (ENSO) OUTLOOK AND OTHER CLIMATE CONDITIONS RELEVANT TO  
THE SEASONAL OUTLOOK. EL NINO CONDITIONS ARE CURRENTLY PRESENT WITH EQUATORIAL  
SEA SURFACE TEMPERATURES (SSTS) ABOVE-AVERAGE ACROSS THE CENTRAL AND EASTERN  
PACIFIC OCEAN, AND NEAR-TO-BELOW-AVERAGE IN THE WESTERN PACIFIC OCEAN.  
ABOVE-AVERAGE SUBSURFACE TEMPERATURES HAVE STRENGTHENED AND PERSISTED ACROSS  
MOST OF THE EQUATORIAL PACIFIC OCEAN. LOW-LEVEL WESTERLY WIND ANOMALIES WERE  
EVIDENT OVER THE CENTRAL AND EAST-CENTRAL EQUATORIAL PACIFIC OCEAN, AND  
UPPER-LEVEL WIND ANOMALIES WERE EASTERLY OVER THE EAST-CENTRAL EQUATORIAL  
PACIFIC AND WESTERLY OVER THE EASTERN EQUATORIAL PACIFIC. ENHANCED CONVECTION  
AND PRECIPITATION WAS EVIDENT ON THE EQUATOR NEAR THE DATE LINE AND PARTS OF  
THE EASTERN PACIFIC, WHILE SUPPRESSED CONVECTION AND PRECIPITATION WAS OBSERVED  
OVER THE PHILIPPINES AND SOUTH OF THE EQUATOR FROM INDONESIA TO THE CENTRAL  
PACIFIC OCEAN. EL NINO CONDITIONS ARE EXPECTED TO STRENGTHEN IN THE NORTHERN  
HEMISPHERE WINTER 2026-27. THE HAWAII SEASONAL OUTLOOK FOR TEMPERATURE AND  
PRECIPITATION IS BASED PRIMARILY ON DYNAMICAL MODEL FORECASTS FROM THE NMME AND  
STATISTICAL FORECASTS (CCA, CA, ENSO-OCN, AND OCN).  
 
ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE PREDICTED IN THE  
OUTLOOK FOR LIHUE, HONOLULU, KAHULUI AND HILO BEGINNING IN  
JULY-AUGUST-SEPTEMBER (JAS) AND CONTINUING THROUGH NOVEMBER-DECEMBER-JANUARY  
(NDJ) 2026-27, SUPPORTED BY NEARLY ALL DYNAMICAL MODEL FORECASTS FROM THE NMME  
AND C3S. DUE TO INCREASING UNCERTAINTY IN FORECAST GUIDANCE AT LONGER LEADS,  
EQUAL CHANCES (EC) FOR ABOVE, NEAR OR BELOW NORMAL TEMPERATURES ARE INDICATED  
FOR HAWAII BEGINNING IN DECEMBER-JANUARY-FEBRUARY (DJF) 2026-27 AND EXTENDING  
THROUGH LONGER LEADS.  
 
ENHANCED PROBABILITIES FOR ABOVE NORMAL PRECIPITATION ARE FORECAST OVER ALL  
HAWAIIAN ISLANDS, KAUAI, OAHU, MAUI AND THE BIG ISLAND, FROM JAS 2026 TO  
AUGUST-SEPTEMBER-OCTOBER (ASO) 2026. EC IS INDICATED FOR  
SEPTEMBER-OCTOBER-NOVEMBER (SON) AND BELOW NORMAL PRECIPITATION IS PREDICTED  
FOR OCTOBER-NOVEMBER-DECEMBER (OND) 2026 TO NDJ 2026-2027 CONSISTENT WITH MOST  
DYNAMICAL MODEL FORECASTS FROM THE NMME AND STATISTICAL FORECASTS, INCLUDING  
CCA, CA, ENSO-OCN, AND NMME CONSOLIDATION. DUE TO CONSIDERABLE UNCERTAINTY IN  
THE PRECIPITATION FORECASTS FROM DYNAMICAL AND STATISTICAL MODELS AND THE  
DECREASE IN FORECAST SIGNAL, EC IS INDICATED OVER THE HAWAIIAN ISLANDS  
BEGINNING IN DJF 2026-2027 AND EXTENDING THROUGH LONGER LEADS.  
 
HILO  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2026 A70 76.1 0.4 A50 25.2 28.6 33.4  
ASO 2026 A70 76.4 0.4 A50 26.1 28.8 33.3  
SON 2026 A70 76.2 0.4 EC 24.3 30.2 40.8  
OND 2026 A60 75.5 0.4 B40 28.3 34.5 42.0  
NDJ 2026 A60 74.2 0.4 B40 26.4 36.6 43.0  
DJF 2027 EC 72.8 0.4 EC 19.6 30.2 33.3  
JFM 2027 EC 71.8 0.4 EC 22.0 32.0 44.5  
FMA 2027 EC 71.7 0.4 EC 24.6 34.1 45.5  
MAM 2027 EC 72.0 0.5 EC 22.5 28.4 34.0  
AMJ 2027 EC 72.9 0.5 EC 21.4 23.7 29.0  
MJJ 2027 EC 74.0 0.4 EC 20.2 27.5 29.1  
JJA 2027 EC 75.2 0.4 EC 19.4 27.2 31.4  
JAS 2027 EC 76.1 0.4 EC 25.2 28.6 33.4  
KAHULUI  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2026 A70 79.0 0.4 A50 0.8 1.1 1.6  
ASO 2026 A70 79.4 0.4 A40 0.8 1.6 2.5  
SON 2026 A70 79.1 0.4 EC 2.1 3.3 4.8  
OND 2026 A60 77.8 0.4 B40 4.2 5.3 8.1  
NDJ 2026 A50 75.9 0.4 B40 5.2 7.6 9.5  
DJF 2027 EC 73.8 0.4 EC 4.6 6.9 8.7  
JFM 2027 EC 72.5 0.4 EC 4.2 6.2 8.2  
FMA 2027 EC 72.3 0.4 EC 3.2 4.1 6.4  
MAM 2027 EC 73.0 0.4 EC 2.5 3.5 4.6  
AMJ 2027 EC 74.3 0.5 EC 1.2 1.6 2.2  
MJJ 2027 EC 76.0 0.5 EC 0.7 1.1 1.8  
JJA 2027 EC 77.7 0.4 EC 0.7 1.1 1.5  
JAS 2027 EC 79.0 0.4 EC 0.8 1.1 1.6  
HONOLULU  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2026 A70 81.3 0.4 A40 1.0 1.4 1.7  
ASO 2026 A70 81.7 0.4 A40 1.6 2.4 3.1  
SON 2026 A70 81.4 0.4 EC 2.5 4.0 5.6  
OND 2026 A60 80.0 0.4 B40 4.4 6.4 8.5  
NDJ 2026 A50 77.7 0.5 B40 3.9 5.6 8.8  
DJF 2027 EC 75.3 0.5 EC 3.7 5.6 8.6  
JFM 2027 EC 73.9 0.4 EC 2.1 4.6 7.8  
FMA 2027 EC 73.8 0.4 EC 1.9 3.2 4.7  
MAM 2027 EC 74.8 0.4 EC 1.8 2.6 3.0  
AMJ 2027 EC 76.3 0.4 EC 1.2 1.6 1.8  
MJJ 2027 EC 78.2 0.4 EC 0.8 1.4 1.6  
JJA 2027 EC 79.9 0.4 EC 0.7 0.8 1.3  
JAS 2027 EC 81.3 0.4 EC 1.0 1.4 1.7  
LIHUE  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2026 A70 79.0 0.3 A40 5.3 6.1 7.8  
ASO 2026 A70 79.4 0.3 A40 6.2 7.9 8.4  
SON 2026 A60 79.1 0.3 EC 9.2 10.0 11.2  
OND 2026 A40 77.8 0.3 B40 9.2 11.7 15.6  
NDJ 2026 A40 75.7 0.3 B40 8.6 12.1 16.9  
DJF 2027 EC 73.6 0.4 EC 7.5 8.4 14.0  
JFM 2027 EC 72.2 0.4 EC 6.5 8.8 13.8  
FMA 2027 EC 72.1 0.5 EC 5.8 8.4 9.9  
MAM 2027 EC 72.8 0.5 EC 5.3 6.6 8.0  
AMJ 2027 EC 74.2 0.5 EC 4.7 5.5 6.0  
MJJ 2027 EC 76.0 0.5 EC 4.9 5.4 5.9  
JJA 2027 EC 77.7 0.4 EC 4.4 5.3 6.9  
JAS 2027 EC 79.0 0.3 EC 5.3 6.1 7.8  
FORECASTER: LUKE HE  
 
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 JUL 16, 2026.  
 

 
 
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