694  
FXHW40 KWBC 151230  
PMDHCO  
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD  
830AM EDT THU MAY 15 2025  
 
MONTHLY FORECAST DISCUSSION VALID JUNE 2025  
 
SEA-SURFACE TEMPERATURE (SST) ANOMALIES IN THE RANGE OF +0.5 TO +1.5 DEGREES  
CELSIUS (C) WERE OBSERVED AROUND THE HAWAIIAN ISLANDS (KAUAI, OAHU, MAUI AND  
THE BIG ISLAND) DURING THE PREVIOUS WEEK.  
 
FROM JANUARY THROUGH APRIL 2025, RAINFALL TOTAL ACCUMULATIONS WERE:  
 
LIHUE AIRPORT 7.76 INCHES (55 PERCENT OF AVERAGE)  
 
HONOLULU AIRPORT 8.24 INCHES (119 PERCENT OF AVERAGE)  
 
KAHULUI AIRPORT 6.39 INCHES (76 PERCENT OF AVERAGE)  
 
HILO AIRPORT 20.25 INCHES (50 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 JUNE 2025. SOME MODELS PREDICT WEAK OR NEAR ZERO  
SST ANOMALIES NEAR THE SOUTHEASTERN HAWAIIAN ISLANDS IN JUNE 2025. ABOVE NORMAL  
TEMPERATURES ARE FAVORED FOR ALL OF THE HAWAIIAN ISLANDS (KAUAI, OAHU, MAUI AND  
HAWAII OR THE BIG ISLAND) FOR JUNE WITH LOWER PROBABILITIES INDICATED FOR THE  
SOUTHEASTERN ISLANDS OF MAUI (KAHULUI) AND HAWAII (HILO), BASED ON MODEL  
FORECASTS.  
 
FOR THE JUNE 2025 PRECIPITATION OUTLOOK, MOST MODELS OF THE NMME AND IMME  
PREDICT ABOVE NORMAL PRECIPITATION ACROSS KAUAI AND OAHU. MOST MODELS OF THE  
NMME AND IMME ALSO PREDICT BELOW NORMAL PRECIPITATION FOR THE BIG ISLAND OF  
HAWAII IN JUNE. EQUAL CHANCES (EC) FOR ABOVE, NEAR OR BELOW NORMAL  
PRECIPITATION ARE INDICATED FOR MAUI, WHERE FORECAST MODELS HAVE MIXED OUTCOMES  
AND WEAK SIGNALS.  
 
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
HILO A60 75.4 0.4 B40 5.3 6.3 8.7  
KAHULUI A65 78.0 0.5 EC 0.1 0.1 0.2  
HONOLULU A70 80.3 0.4 A40 0.1 0.2 0.3  
LIHUE A70 78.1 0.4 A45 1.1 1.3 1.6  
 
SEASONAL FORECAST DISCUSSION VALID JJA 2025 - JJA 2026  
 
REFER TO THE PROGNOSTIC DISCUSSION OF THE LONG-LEAD SEASONAL OUTLOOKS FOR THE  
CONTIGUOUS U.S. (CONUS) AND ALASKA FOR A DESCRIPTION OF THE EL NIñO SOUTHERN  
OSCILLATION (ENSO) OUTLOOK AND OTHER CLIMATE CONDITIONS RELEVANT TO THE  
SEASONAL OUTLOOK. ENSO-NEUTRAL CONDITIONS CONTINUED OVER THE PACIFIC OCEAN  
THROUGH APRIL. EQUATORIAL SST ANOMALIES ARE NEAR ZERO ACROSS MUCH OF THE  
PACIFIC OCEAN. WEAK NEGATIVE SST ANOMALIES ARE OBSERVED OVER PARTS OF THE  
EASTERN EQUATORIAL PACIFIC OCEAN, WHILE WEAK POSITIVE SST ANOMALIES ARE  
OBSERVED OVER THE FAR WESTERN PACIFIC OCEAN NEAR THE MARITIME ISLANDS. NEGATIVE  
SUBSURFACE TEMPERATURE ANOMALIES IN THE CENTRAL PACIFIC OCEAN HAVE DISSIPATED  
IN THE LAST SEVERAL WEEKS. POSITIVE SUBSURFACE TEMPERATURE ANOMALIES PERSIST AT  
DEPTHS OF 50 TO 300 METERS IN THE WESTERN EQUATORIAL PACIFIC OCEAN. LOW-LEVEL  
(850-HPA) WIND ANOMALIES ARE NEAR ZERO ACROSS MOST OF THE EQUATORIAL PACIFIC  
OCEAN. UPPER-LEVEL (200-HPA) WIND ANOMALIES ARE NEAR ZERO ACROSS MOST OF THE  
PACIFIC OCEAN, WHILE SOUTHERLY CROSS-EQUATORIAL UPPER-LEVEL WIND ANOMALIES ARE  
OBSERVED OVER THE WESTERN PACIFIC OCEAN. SUPPRESSED CONVECTION AND  
PRECIPITATION WERE OBSERVED OVER THE WESTERN AND CENTRAL PACIFIC OCEAN TO THE  
NORTH OF THE EQUATOR, WHILE ENHANCED CONVECTION AND PRECIPITATION WERE OBSERVED  
OVER PARTS OF THE MARITIME ISLANDS TO THE WEST.  
 
MOST DYNAMICAL AND STATISTICAL MODELS PREDICT A CONTINUATION OF ENSO-NEUTRAL  
CONDITIONS INTO BOREAL SUMMER. SOME MODELS, SUCH AS THE CPC SST CANONICAL  
CORRELATION ANALYSIS (CCA) PREDICT THE DEVELOPMENT OF A LA NIñA IN AUTUMN BY  
FORECASTS OF NEGATIVE NIñO 3.4 REGION SST ANOMALIES BELOW THE -0.5 C  
THRESHOLD. ENSO-NEUTRAL CONDITIONS ARE FORECAST IN THE CPC ENSO OUTLOOK WITH A  
GREATER PROBABILITY THAN LA NIñA THROUGH THE DECEMBER-JANUARY-FEBRUARY SEASON,  
ALTHOUGH THE PROBABILITY OF THE DEVELOPMENT OF LA NIñA INCREASES THROUGH THE  
NORTHERN HEMISPHERE AUTUMN AND WINTER, WITH SOME STATISTICAL TOOLS INDICATING  
LA NIñA IS MORE LIKELY. DEVELOPMENT OF LA NIñA WOULD ALTER THE PROBABILITIES  
OF PRECIPITATION FOR THE HAWAIIAN ISLANDS, ESPECIALLY IN BOREAL WINTER, BUT THE  
STATE OF ENSO AT LONGER LEAD TIMES IS SOMEWHAT UNCERTAIN AS OF SPRING 2025.  
 
ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE INDICATED IN THE  
OFFICIAL OUTLOOK FOR LIHUE, HONOLULU, KAHULUI AND HILO FOR JJA  
(JUNE-JULY-AUGUST) THROUGH OCTOBER-NOVEMBER-DECEMBER (OND) 2025, SUPPORTED BY  
NEARLY ALL DYNAMICAL MODEL FORECASTS FROM THE NMME AND C3S, AS WELL AS DECADAL  
TIMESCALE TEMPERATURE TRENDS. PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE  
GREATER FOR NORTHWESTERN ISLANDS OF HAWAII, EXCEEDING 70 PERCENT IN EARLY  
SEASONS, FOLLOWING CALIBRATED MODEL GUIDANCE FROM THE NMME. DUE TO INCREASING  
UNCERTAINTY IN THE STATE OF ENSO AND WEAKENING SIGNALS IN FORECAST GUIDANCE AT  
LONGER LEADS, EQUAL CHANCES (EC) FOR ABOVE, NEAR OR BELOW NORMAL TEMPERATURES  
ARE INDICATED FOR HAWAII BEGINNING IN NDJ (NOVEMBER-DECEMBER-JANUARY) 2025 AND  
EXTENDING THROUGH LONGER LEADS.  
 
ENHANCED PROBABILITIES FOR ABOVE NORMAL PRECIPITATION ARE FORECAST OVER THE  
NORTHWESTERN HAWAIIAN ISLANDS OF KAUAI AND OAHU FROM JJA TO  
AUGUST-SEPTEMBER-OCTOBER (ASO) 2025, CONSISTENT WITH MOST DYNAMICAL MODEL  
FORECASTS, AS WELL DECADAL TRENDS. DYNAMICAL MODEL FORECASTS OF POSITIVE SST  
ANOMALIES SURROUNDING THE NORTHWESTERN HAWAIIAN ISLANDS ALSO SUPPORT FORECASTS  
OF ABOVE NORMAL PRECIPITATION. ENHANCED PROBABILITIES FOR BELOW NORMAL  
PRECIPITATION ARE FORECAST FOR THE SOUTHEASTERN BIG ISLAND OF HAWAII FROM JJA  
TO SEPTEMBER-OCTOBER-NOVEMBER (SON) 2025, CONSISTENT WITH MOST DYNAMICAL MODEL  
FORECASTS, AS WELL DECADAL TIMESCALE PRECIPITATION TRENDS. EQUAL CHANCES (EC)  
FOR ABOVE, NEAR OR BELOW NORMAL PRECIPITATION ARE INDICATED FOR MAUI (KAHULUI)  
FOR ALL OUTLOOKS, WITH UNCERTAINTY IN THE TRANSITION FROM WETTER CONDITIONS TO  
THE NORTHWEST AND DRIER CONDITIONS TO THE SOUTHEAST. BEGINNING IN OND 2025 FOR  
THE BIG ISLAND AND SON 2025 FOR NORTHWESTERN ISLANDS OF KAUAI AND OAHU AND  
EXTENDING THROUGH LONGER LEADS, EC IS INDICATED IN THE SEASONAL PRECIPITATION  
OUTLOOK. UNCERTAINTY IN THE STATE OF ENSO BEGINNING IN OND 2025 RESULTS IN  
WEAKER SIGNALS AND NEAR CLIMATOLOGICAL PROBABILITIES IN THE SEASONAL OUTLOOK.  
 
HILO  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JJA 2025 A65 75.2 0.4 B40 19.4 27.2 31.4  
JAS 2025 A65 76.1 0.4 B40 25.2 28.6 33.4  
ASO 2025 A60 76.4 0.4 B40 26.1 28.8 33.3  
SON 2025 A60 76.2 0.4 B40 24.3 30.2 40.8  
OND 2025 A60 75.5 0.4 EC 28.3 34.5 42.0  
NDJ 2025 EC 74.2 0.4 EC 26.4 36.6 43.0  
DJF 2026 EC 72.8 0.4 EC 19.6 30.2 33.3  
JFM 2026 EC 71.8 0.4 EC 22.0 32.0 44.5  
FMA 2026 EC 71.7 0.4 EC 24.6 34.1 45.5  
MAM 2026 EC 72.0 0.5 EC 22.5 28.4 34.0  
AMJ 2026 EC 72.9 0.5 EC 21.4 23.7 29.0  
MJJ 2026 EC 74.0 0.4 EC 20.2 27.5 29.1  
JJA 2026 EC 75.2 0.4 EC 19.4 27.2 31.4  
KAHULUI  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JJA 2025 A70 77.7 0.4 EC 0.7 1.1 1.5  
JAS 2025 A70 79.0 0.4 EC 0.8 1.1 1.6  
ASO 2025 A70 79.4 0.4 EC 0.8 1.6 2.5  
SON 2025 A65 79.1 0.4 EC 2.1 3.3 4.8  
OND 2025 A60 77.8 0.4 EC 4.2 5.3 8.1  
NDJ 2025 EC 75.9 0.4 EC 5.2 7.6 9.5  
DJF 2026 EC 73.8 0.4 EC 4.6 6.9 8.7  
JFM 2026 EC 72.5 0.4 EC 4.2 6.2 8.2  
FMA 2026 EC 72.3 0.4 EC 3.2 4.1 6.4  
MAM 2026 EC 73.0 0.4 EC 2.5 3.5 4.6  
AMJ 2026 EC 74.3 0.5 EC 1.2 1.6 2.2  
MJJ 2026 EC 76.0 0.5 EC 0.7 1.1 1.8  
JJA 2026 EC 77.7 0.4 EC 0.7 1.1 1.5  
HONOLULU  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JJA 2025 A70 79.9 0.4 A40 0.7 0.8 1.3  
JAS 2025 A70 81.3 0.4 A40 1.0 1.4 1.7  
ASO 2025 A70 81.7 0.4 A40 1.6 2.4 3.1  
SON 2025 A65 81.4 0.4 EC 2.5 4.0 5.6  
OND 2025 A60 80.0 0.4 EC 4.4 6.4 8.5  
NDJ 2025 EC 77.7 0.5 EC 3.9 5.6 8.8  
DJF 2026 EC 75.3 0.5 EC 3.7 5.6 8.6  
JFM 2026 EC 73.9 0.4 EC 2.1 4.6 7.8  
FMA 2026 EC 73.8 0.4 EC 1.9 3.2 4.7  
MAM 2026 EC 74.8 0.4 EC 1.8 2.6 3.0  
AMJ 2026 EC 76.3 0.4 EC 1.2 1.6 1.8  
MJJ 2026 EC 78.2 0.4 EC 0.8 1.4 1.6  
JJA 2026 EC 79.9 0.4 EC 0.7 0.8 1.3  
LIHUE  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JJA 2025 A70 77.7 0.4 A40 4.4 5.3 6.9  
JAS 2025 A70 79.0 0.3 A40 5.3 6.1 7.8  
ASO 2025 A70 79.4 0.3 A40 6.2 7.9 8.4  
SON 2025 A65 79.1 0.3 EC 9.2 10.0 11.2  
OND 2025 A60 77.8 0.3 EC 9.2 11.7 15.6  
NDJ 2025 EC 75.7 0.3 EC 8.6 12.1 16.9  
DJF 2026 EC 73.6 0.4 EC 7.5 8.4 14.0  
JFM 2026 EC 72.2 0.4 EC 6.5 8.8 13.8  
FMA 2026 EC 72.1 0.5 EC 5.8 8.4 9.9  
MAM 2026 EC 72.8 0.5 EC 5.3 6.6 8.0  
AMJ 2026 EC 74.2 0.5 EC 4.7 5.5 6.0  
MJJ 2026 EC 76.0 0.5 EC 4.9 5.4 5.9  
JJA 2026 EC 77.7 0.4 EC 4.4 5.3 6.9  
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 JUN 19, 2025.  
 
 
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