715  
FXHW40 KWBC 191230  
PMDHCO  
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD  
830AM EDT THU JUN 19 2025  
 
MONTHLY FORECAST DISCUSSION VALID JULY 2025  
 
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 2025, RAINFALL TOTAL ACCUMULATIONS WERE:  
 
LIHUE AIRPORT 8.64 INCHES (53 PERCENT OF AVERAGE)  
 
HONOLULU AIRPORT 8.82 INCHES (114 PERCENT OF AVERAGE)  
 
KAHULUI AIRPORT 6.44 INCHES (71 PERCENT OF AVERAGE)  
 
HILO AIRPORT 24.76 INCHES (53 PERCENT OF AVERAGE)  
 
MOST CLIMATE MODELS OF THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) AND THE  
INTERNATIONAL MULTI-MODEL ENSEMBLE (IMME/C3S) PREDICT NEAR TO SLIGHTLY ABOVE  
NORMAL SSTS FOR THE BIG ISLAND IN JULY 2025, WITH SOMEWHAT HIGHER PROBABILITIES  
FAVORING ABOVE NORMAL SSTS FOR THE REMAINDER OF THE ISLAND CHAIN. AS IS MOST  
OFTEN THE CASE, THE HAWAIIAN SURFACE TEMPERATURE PATTERN MIRRORS THAT OF THE  
SURROUNDING SST ANOMALY PATTERN.  
 
FOR THE JULY 2025 PRECIPITATION OUTLOOK, THERE IS SUBSTANTIAL VARIANCE BETWEEN  
THE MODELS OF THE NMME AND IMME/C3S. HOWEVER, THE GENERAL TENDENCY FAVORS A  
RELATIVELY DRY PATTERN FOR THE BIG ISLAND AND MAUI, WITH INCREASING CHANCES OF  
RELATIVE WETNESS NORTHWESTWARD FROM MAUI (I.E. WITH WETNESS BEING SLIGHTLY MORE  
LIKELY FOR KAUAI THAN FOR OAHU). A FEW MODELS (CFS, CANESM5, AND THE NCAR  
CCSM4) FAVOR BELOW-NORMAL PRECIPITATION ACROSS THE ENTIRE ARCHIPELAGO.  
 
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
HILO A40 76.2 0.4 B50 7.1 9.5 11.4  
KAHULUI A45 79.2 0.4 B40 0.2 0.4 0.5  
HONOLULU A50 81.4 0.5 EC 0.2 0.4 0.5  
LIHUE A50 79.2 0.4 A40 1.5 1.7 1.9  
 
SEASONAL FORECAST DISCUSSION VALID JAS 2025 - JAS 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 MAY. EQUATORIAL SST ANOMALIES ARE NEAR TO SLIGHTLY ABOVE NORMAL ACROSS  
MUCH OF THE PACIFIC OCEAN. WEAK NEGATIVE SST ANOMALIES ARE OBSERVED OVER PARTS  
OF THE EASTERN EQUATORIAL PACIFIC OCEAN. NEGATIVE SUBSURFACE TEMPERATURE  
ANOMALIES IN THE CENTRAL PACIFIC OCEAN HAVE DISSIPATED IN THE LAST SEVERAL  
WEEKS. POSITIVE SUBSURFACE TEMPERATURE ANOMALIES PERSIST AT DEPTHS OF 75 TO 200  
METERS IN THE WESTERN EQUATORIAL PACIFIC OCEAN. LOW-LEVEL (850-HPA) WIND  
ANOMALIES ARE EASTERLY OVER THE EAST-CENTRAL PACIFIC, AND UPPER-LEVEL (200-HPA)  
WIND ANOMALIES ARE NEAR AVERAGE ACROSS MOST OF THE PACIFIC OCEAN. ENHANCED  
CONVECTION AND PRECIPITATION WERE OBSERVED OVER INDONESIA. COLLECTIVELY, THE  
COUPLED OCEAN-ATMOSPHERE SYSTEM REFLECTS ENSO-NEUTRAL. MOST DYNAMICAL AND  
STATISTICAL MODELS PREDICT A CONTINUATION OF ENSO-NEUTRAL CONDITIONS THROUGH  
BOREAL SUMMER. SOME MODELS, SUCH AS THE CPC SST CANONICAL CORRELATION ANALYSIS  
(CCA) PREDICT THE DEVELOPMENT OF A LA NIñA IN SUMMER BY FORECASTS OF NEGATIVE  
NIñO 3.4 REGION SST ANOMALIES REACHING THE -0.5 C THRESHOLD IN JJA 2025,  
DIPPING TO A MINIMUM OF ABOUT -1.2 C (MODERATE INTENSITY LA NIñA) IN NDJ AND  
DJF 2025-26, AND THEN RECOVERING TO JUST ABOVE THE -0.5 C THRESHOLD BY NEXT  
SPRING (AMJ 2026). ENSO-NEUTRAL CONDITIONS ARE FORECAST IN THE CPC ENSO OUTLOOK  
WITH A GREATER PROBABILITY THAN LA NIñA THROUGH THE JANUARY-FEBRUARY-MARCH  
(JFM) 2026 SEASON, ALTHOUGH THE PROBABILITY OF THE DEVELOPMENT OF LA NIñA  
INCREASES THROUGH THE NORTHERN HEMISPHERE AUTUMN AND WINTER, COMING TO WITHIN  
TEN PERCENTAGE POINTS DURING OND AND NDJ. 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 LATE SPRING 2025.  
 
ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE INDICATED IN THE  
OFFICIAL OUTLOOK FOR LIHUE, HONOLULU, AND KAHULUI FROM JAS  
(JULY-AUGUST-SEPTEMBER) THROUGH OCTOBER-NOVEMBER-DECEMBER (OND) 2025, FAVORED  
BY MOST NMME AND AVAILABLE C3S DYNAMICAL MODELS AND DECADAL TEMPERATURE TRENDS.  
MOST MODEL GUIDANCE SUPPORTS EQUAL CHANCES (EC) OF ABOVE, NEAR, AND BELOW  
NORMAL SEASONAL MEAN TEMPERATURES FOR THE BIG ISLAND THROUGH OND, THOUGH A  
SUBSTANTIAL NUMBER OF MODELS SUPPORT A WEAK TILT TOWARDS ABOVE NORMAL  
TEMPERATURES. BY NDJ, THE TEMPERATURE OUTLOOK FOR ALL OF THE ISLANDS IS FAVORED  
TO BE ABOVE NORMAL. THE CHANCES FOR ABOVE NORMAL TEMPERATURES ARE GREATER FOR  
NORTHWESTERN ISLANDS OF HAWAII, AND GRADUALLY DIMINISH TOWARDS THE SOUTHEASTERN  
ISLANDS.  
 
ENHANCED PROBABILITIES FOR BELOW NORMAL PRECIPITATION ARE INDICATED OVER THE  
BIG ISLAND OF HAWAII, MAUI, AND OAHU FROM JAS THROUGH  
SEPTEMBER-OCTOBER-NOVEMBER (SON) 2025, CONSISTENT WITH MOST DYNAMICAL MODEL  
FORECASTS, AS WELL AS DECADAL TRENDS. FOR KAUAI, WEAK OR CONFLICTING SIGNALS  
WARRANTS EC FOR JAS, FOLLOWED BY A SLIGHT TILT TOWARDS BELOW NORMAL  
PRECIPITATION IN BOTH ASO AND SON. FOR THE AUTUMN AND EARLY WINTER SEASONS OF  
OND AND NDJ, A TRANSITION TOWARDS AN ANOMALOUSLY WET PATTERN IS PREDICTED BY  
THE NMME AND ITS CONSTITUENT MODELS, INITIALLY FAVORING A FORECAST OF EC FOR  
MOST ISLANDS IN OND, AND COMPLETING THE TRANSITION TO A WETTER PATTERN IN NDJ.  
THE DYNAMICAL MODEL FORECASTS DEPICT KAUAI AS MOST LIKELY TO COMPLETE THE  
TRANSITION TO A WETTER-THAN-NORMAL PATTERN FIRST, FAVORING ABOVE NORMAL  
PRECIPITATION AS EARLY AS OND. THIS IS CONSISTENT WITH AN EXPECTED ENSO-NEUTRAL  
BACKGROUND AND GENERALLY NEAR-AVERAGE TRADE WINDS, WITH CONSIDERATION OF  
SIGNIFICANT PROBABILITIES FOR A LA NIñA EVENT AS WELL.  
 
HILO  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2025 EC 76.1 0.4 B60 25.2 28.6 33.4  
ASO 2025 EC 76.4 0.4 B50 26.1 28.8 33.3  
SON 2025 EC 76.2 0.4 B40 24.3 30.2 40.8  
OND 2025 EC 75.5 0.4 EC 28.3 34.5 42.0  
NDJ 2025 A40 74.2 0.4 A40 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  
JAS 2026 EC 76.1 0.4 EC 25.2 28.6 33.4  
KAHULUI  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2025 A40 79.0 0.4 B55 0.8 1.1 1.6  
ASO 2025 A45 79.4 0.4 B45 0.8 1.6 2.5  
SON 2025 A45 79.1 0.4 B40 2.1 3.3 4.8  
OND 2025 A45 77.8 0.4 EC 4.2 5.3 8.1  
NDJ 2025 A40 75.9 0.4 A40 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  
JAS 2026 EC 79.0 0.4 EC 0.8 1.1 1.6  
HONOLULU  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2025 A50 81.3 0.4 B45 1.0 1.4 1.7  
ASO 2025 A50 81.7 0.4 B45 1.6 2.4 3.1  
SON 2025 A55 81.4 0.4 B40 2.5 4.0 5.6  
OND 2025 A45 80.0 0.4 EC 4.4 6.4 8.5  
NDJ 2025 A40 77.7 0.5 A45 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  
JAS 2026 EC 81.3 0.4 EC 1.0 1.4 1.7  
LIHUE  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
JAS 2025 A55 79.0 0.3 EC 5.3 6.1 7.8  
ASO 2025 A60 79.4 0.3 B40 6.2 7.9 8.4  
SON 2025 A60 79.1 0.3 B40 9.2 10.0 11.2  
OND 2025 A50 77.8 0.3 A40 9.2 11.7 15.6  
NDJ 2025 A40 75.7 0.3 A50 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  
JAS 2026 EC 79.0 0.3 EC 5.3 6.1 7.8  
FORECASTER: ANTHONY ARTUSA  
 
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 17, 2025.  
 

 
 
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