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FXUS05 KWBC 181231
PMD90D
PROGNOSTIC DISCUSSION FOR LONG-LEAD SEASONAL OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830 AM EDT THU JUN 18 2026
SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS
EL NINO CONDITIONS HAVE RECENTLY DEVELOPED IN THE TROPICS AND ARE EXPECTED TO
STRENGTHEN IN THE BOREAL SUMMER AND AUTUMN OF 2026. THE NOAA EL NINO SOUTHERN
OSCILLATION (ENSO) OUTLOOK PREDICTS A GREATER THAN 40 PERCENT CHANCE OF THIS EL
NINO EVENT BECOMING STRONG BY THE JULY-AUGUST-SEPTEMBER (JAS) SEASON, AS
DETERMINED BY THE RELATIVE ANOMALY OF THE NINO 3.4 REGION TO THE GLOBAL
TROPICAL SEA SURFACE TEMPERATURE ANOMALY.
THE JAS SEASONAL OUTLOOK FOR TEMPERATURE FAVORS ABOVE NORMAL TEMPERATURES
ACROSS MOST OF ALASKA, EXCLUDING PARTS OF THE NORTHEASTERN MAINLAND. ABOVE
NORMAL TEMPERATURES ARE LIKELY FOR MUCH OF THE WESTERN CONTIGUOUS UNITED STATES
(CONUS), WITH THE HIGHEST PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ACROSS
THE PACIFIC NORTHWEST. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE LOWER
MISSISSIPPI VALLEY, THE SOUTHEAST, AND THE EASTERN SEABOARD, WITH HIGHEST
PROBABILITIES ALONG THE COAST OF NEW ENGLAND AND ENHANCED PROBABILITIES ALONG
THE REMAINDER OF THE EAST COAST AND FLORIDA.
THE JAS SEASONAL OUTLOOK FOR PRECIPITATION FAVORS ABOVE NORMAL PRECIPITATION
FOR NORTHWESTERN MAINLAND ALASKA AND THE ALEUTIAN ISLANDS, WHILE BELOW NORMAL
PRECIPITATION IS FAVORED FOR SOUTHERN AREAS OF SOUTHEAST ALASKA. BELOW NORMAL
PRECIPITATION IS ALSO FAVORED FOR A SMALL AREA OF THE PACIFIC NORTHWEST, PARTS
OF THE SOUTHERN PLAINS AND LOWER MISSISSIPPI VALLEY, AND THE WESTERN GREAT
LAKES REGION. ABOVE NORMAL PRECIPITATION IS FAVORED FOR AN EXPANDED AREA OF THE
WEST, AND SLIGHTLY FAVORED FOR COASTAL AREAS OF THE MID-ATLANTIC AND NORTHEAST.
BASIS AND SUMMARY OF THE CURRENT LONG-LEAD OUTLOOKS
NOTE: FOR GRAPHICAL DISPLAYS OF THE FORECAST TOOLS DISCUSSED BELOW SEE:
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/PREDICTIONS/90DAY/TOOLS/BRIEFING
CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS
THE MOST RECENT WEEKLY MEAN SEA SURFACE TEMPERATURE (SST) ANOMALY FOR THE NINO
3.4 REGION RELATIVE TO THE GLOBAL TROPICS IS +0.9 DEGREES C, INDICATING WEAK EL
NINO CONDITIONS. SST ANOMALIES HAVE INCREASED ACROSS THE CENTRAL AND EASTERN
EQUATORIAL PACIFIC OCEAN IN RECENT WEEKS. POSITIVE OCEAN TEMPERATURE ANOMALIES
PERSIST ACROSS MOST OF THE EQUATORIAL PACIFIC OCEAN FROM THE SURFACE TO DEPTHS
OF 200 METERS OR GREATER IN THE EASTERN PACIFIC. NEGATIVE OUTGOING LONGWAVE
RADIATION (OLR) ANOMALIES ARE PRESENT NEAR THE DATE LINE AND OVER PARTS OF THE
EASTERN PACIFIC TO THE NORTH OF THE EQUATOR, INDICATING ENHANCED CONVECTION AND
PRECIPITATION. POSITIVE OLR ANOMALIES, INDICATING SUPPRESSED CONVECTION AND
PRECIPITATION, ARE PRESENT TO THE SOUTH OF THE EQUATOR FROM PARTS OF THE
MARITIME CONTINENT TO THE DATE LINE. LOW LEVEL (850-HPA) EASTERLY WIND
ANOMALIES WERE PRESENT OVER THE WESTERN AND CENTRAL EQUATORIAL PACIFIC OCEAN IN
RECENT WEEKS. THESE ATMOSPHERE AND OCEAN ANOMALY PATTERNS INDICATE EL NINO
CONDITIONS ARE PRESENT.
POSITIVE SST ANOMALIES ARE OBSERVED NEAR THE COAST OF SOUTHERN CALIFORNIA.
NEGATIVE SST ANOMALIES ARE PRESENTLY NEAR THE CENTRAL GULF AND MID-ATLANTIC
COASTS. PERSISTENT COASTAL SST ANOMALIES MAY INFLUENCE SEASONAL TEMPERATURES OF
ADJACENT AREAS.
PROGNOSTIC DISCUSSION OF SST FORECASTS
MOST SST FORECASTS FROM THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) AND THE
COPERNICUS CLIMATE CHANGE SERVICE (C3S) MULTI-MODEL ENSEMBLE PREDICT THAT
RELATIVE NINO 3.4 ANOMALIES WILL EXCEED +1.0 DEGREES C BY JAS 2026. THE NMME
MULTI-MODEL MEAN FORECAST EXCEEDS +2.0 DEGREES C BY THE
OCTOBER-NOVEMBER-DECEMBER (OND) 2026 SEASON. THE CPC SST CONSOLIDATION FORECAST
FOR THE RELATIVE NINO 3.4 INDEX INCREASES THROUGH SUMMER AND AUTUMN TO A PEAK
MEDIAN VALUE OF +1.9 DEGREES C IN THE NOVEMBER-DECEMBER-JANUARY (NDJ) 2026-27
SEASON, BEFORE DECREASING THEREAFTER. THE CONTINUATION OF AN EL NINO EVENT IS
LIKELY THROUGH FMA 2027, ACCORDING TO THE SST CONSOLIDATION, AND THE CPC ENSO
OUTLOOK PREDICTS THAT THE LIKELIHOOD OF A VERY STRONG EVENT WITH A PEAK
SEASONAL RELATIVE NINO 3.4 INDEX GREATER THAN +2.0 DEGREES C EXCEEDS 60
PERCENT.
PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS
THE SEASONAL TEMPERATURE AND PRECIPITATION OUTLOOKS ARE BASED PRIMARILY ON
FORECAST TOOLS DERIVED FROM THE NMME, INCLUDING CALIBRATED VERSIONS, SUCH AS
THE PROBABILITY ANOMALY CORRELATION (PAC) AND THE CALIBRATION, BRIDGING AND
MERGING (CBAM), WHICH CALIBRATES THE DYNAMICAL MODEL FORECASTS USING BAYESIAN
JOINT PROBABILITY (BJP) MODELS, AS WELL AS GENERATING STATISTICAL OR BRIDGING
BJP MODELS OF TEMPERATURE AND PRECIPITATION FROM DYNAMICAL MODEL NINO 3.4
ANOMALY FORECAST PREDICTORS. AN ENSO-OCN FORECAST TOOL IS USED TO REPRESENT THE
COMBINED INFLUENCE OF THE EL NINO SOUTHERN OSCILLATION (ENSO) AND DECADAL
TIMESCALE TRENDS IN TEMPERATURE AND PRECIPITATION, BASED ON THE OPTIMUM CLIMATE
NORMAL (OCN). IMPACTS OF A PREDICTED MODERATE EL NINO MAY INFLUENCE THE
TEMPERATURE AND PRECIPITATION PATTERNS IN THE SUMMER SEASONS FOR SOME REGIONS.
HOWEVER, THE IMPACTS OF EL NINO ON THE CLIMATE OF NORTH AMERICA IS WEAKER IN
SUMMER THAN AUTUMN AND ESPECIALLY WINTER SEASONS. THE SPATIAL PATTERNS OF
TEMPERATURE AND PRECIPITATION ARE INDICATIVE OF A STRONG EL NINO EVENT FROM
AUTUMN THROUGH WINTER AND THE JANUARY-FEBRUARY-MARCH (JFM) 2026 SEASON. DECADAL
VARIABILITY IN TEMPERATURE AND PRECIPITATION ARE GENERALLY THE LARGEST
PREDICTABLE SIGNAL FOR THE SEASONAL FORECASTS, FOLLOWING DIMINISHING IMPACTS OF
EL NINO IN THE SPRING OF 2027. DECADAL VARIABILITY AND TRENDS ARE DETERMINED
FROM THE OCN, CALCULATED FROM THE DIFFERENCE BETWEEN THE MOST RECENT 15-YEAR
PERIOD AVERAGE SEASONAL TEMPERATURE OR PRECIPITATION AND THE AVERAGE FOR THE
CLIMATOLOGY PERIOD FROM 1991-2020. CONSOLIDATIONS OF MULTIPLE STATISTICAL TOOLS
AND WHEN AVAILABLE DYNAMICAL FORECAST TOOLS THAT UTILIZE PAC CALIBRATION ARE
USED THROUGHOUT THE OUTLOOKS FROM JAS 2026 TO JAS 2027.
PROGNOSTIC DISCUSSION OF OUTLOOKS - JAS 2026 TO JAS 2027
TEMPERATURE
THE JAS 2026 TEMPERATURE OUTLOOK FAVORS ABOVE NORMAL TEMPERATURES FOR MUCH OF
ALASKA, EXCLUDING ONLY PARTS OF THE NORTHEASTERN MAINLAND, CONSISTENT WITH NMME
DYNAMICAL MODEL FORECASTS, CBAM, AND THE CONSOLIDATION. THIS TEMPERATURE
PATTERN IS ALSO CONSISTENT WITH POTENTIAL IMPACTS OF EL NINO. ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR MOST OF THE CONUS STARTING IN JAS 2026, TO SOME
EXTENT INFLUENCED BY DECADAL TEMPERATURE TRENDS, WITH VARIATIONS MOSTLY
ATTRIBUTABLE TO EL NINO IMPACTS. ABOVE NORMAL TEMPERATURES ARE LIKELY FOR THE
NORTHWESTERN CONUS WITH PROBABILITIES EXCEEDING 60 PERCENT ACROSS THE PACIFIC
NORTHWEST, WHERE THERE IS CONSISTENCY AMONG FORECAST TOOLS. ABOVE NORMAL
TEMPERATURES ARE ALSO SUPPORTED IN THIS REGION BY POTENTIAL EL NINO IMPACTS AND
NEGATIVE CORRELATIONS BETWEEN SUMMER SEASONAL TEMPERATURES AND PRECIPITATION.
ABOVE NORMAL TEMPERATURES ARE FAVORED WITH WEAKER PROBABILITIES ACROSS THE
SOUTHERN TIER OF THE CONUS SUPPORTED BY CALIBRATED DYNAMICAL MODEL FORECASTS,
AS WELL AS THE ENSO-OCN STATISTICAL FORECAST. GREATER PROBABILITIES FAVORING
ABOVE NORMAL TEMPERATURES OVER THE EASTERN SEABOARD ARE SUPPORTED BY DYNAMICAL
AND STATISTICAL TOOLS, AND CONSISTENT WITH THE OCN REPRESENTATION OF DECADAL
TRENDS. EQUAL CHANCES (EC) OF BELOW, NEAR AND ABOVE NORMAL TEMPERATURES ARE
INDICATED FOR MUCH OF THE NORTHERN CENTRAL CONUS, THE CENTRAL MISSISSIPPI AND
OHIO VALLEYS, AND THE GREAT LAKES REGION, WITH BELOW NORMAL TEMPERATURES
SLIGHTLY FAVORED FOR PARTS OF THE CENTRAL MISSISSIPPI VALLEY. THE INCREASED
PROBABILITY OF BELOW NORMAL TEMPERATURES IS RELATED TO POTENTIAL IMPACTS OF A
DEVELOPING EL NINO, USING THE CBAM BRIDGING OF DYNAMICAL MODEL FORECASTS OF
NINO 3.4 ANOMALIES.
THE TEMPERATURE PATTERN OF THE SEASONAL OUTLOOK CONTINUES THROUGH
AUGUST-SEPTEMBER-OCTOBER (ASO) BEFORE BEING MODIFIED BY CHANGING IMPACTS OF A
PREDICTED STRONG EL NINO. THE TEMPERATURE OUTLOOKS FOR THE OND 2026 THROUGH JFM
2027 SEASONS FAVOR ABOVE NORMAL TEMPERATURES ACROSS ALASKA, MOST OF THE WEST,
AND THE NORTHERN TIER OF THE CONUS, SUPPORTED BY CALIBRATED DYNAMICAL MODELS
AND STATISTICAL REPRESENTATIONS OF THE TYPICAL IMPACTS OF EL NINO. EC IS
INDICATED ACROSS MOST OF THE SOUTHERN TIER OF THE CONUS IN THESE SEASONS, WHERE
EL NINO IMPACTS INCREASE THE PROBABILITY OF NEAR TO BELOW NORMAL TEMPERATURES.
SEASONAL TEMPERATURE PATTERNS IN THE OUTLOOKS FOR THE SPRING AND SUMMER SEASONS
OF 2027 ARE PRIMARILY RELATED TO DECADAL TRENDS.
PRECIPITATION
THE JAS 2026 PRECIPITATION OUTLOOK FAVORS ABOVE NORMAL PRECIPITATION FOR
WESTERN MAINLAND ALASKA AND THE ALEUTIANS, WHILE BELOW NORMAL PRECIPITATION IS
FAVORED FOR A SMALL AREA IN SOUTHERN SOUTHEAST ALASKA, SUPPORTED BY DYNAMICAL
MODEL TOOLS, AS WELL AS THE ENSO-OCN FORECAST. IN THE NEXT SEVERAL SEASONS
THROUGH OND 2026, THE AREA OF FAVORED ABOVE NORMAL PRECIPITATION EXPANDS
EASTWARD ACROSS MAINLAND ALASKA, WHILE THE AREA OF FAVORED BELOW NORMAL
PRECIPITATION IN SOUTHEAST ALASKA DECREASES AND IS REPLACED BY EC. BELOW NORMAL
PRECIPITATION IS FAVORED IN WESTERN WASHINGTON STATE IN JAS 2026, SUPPORTED BY
DYNAMICAL MODEL FORECASTS. IN THE FOLLOWING SEASONS, THE AREA OF FAVORED BELOW
NORMAL PRECIPITATION EXPANDS ACROSS MUCH OF THE NORTHWEST AND EASTWARD INTO
NORTHERN PLAINS BY THE WINTER MONTHS, CONSISTENT WITH CANONICAL EL NINO
IMPACTS. BEGINNING IN DECEMBER-JANUARY-FEBRUARY (DJF) 2026-27, THE AREA OF
FAVORED BELOW NORMAL PRECIPITATION PERSISTS ONLY FROM THE NORTHERN ROCKIES
EASTWARD, BEFORE REDUCING IN EXTENT AND RETURNING TO COVER THE NORTHWESTERN
CONUS, CONSISTENT WITH THE EVOLUTION FROM EL NINO IMPACTS TO DECADAL TRENDS.
ABOVE NORMAL PRECIPITATION IS FAVORED FOR A LARGE AREA OF THE WESTERN CONUS,
FROM SOUTHERN CALIFORNIA AND THE DESERT SOUTHWEST INTO THE GREAT BASIN AND THE
CENTRAL ROCKIES, CONSISTENT WITH NMME AND C3S FORECASTS, AS WELL AS ANOMALOUSLY
WARM EASTERN PACIFIC SSTS AND A POTENTIAL INCREASE IN TROPICAL STORMS. THIS
AREA OF FAVORED ABOVE NORMAL PRECIPITATION EXPANDS EASTWARD IN THE NEXT SEVERAL
SEASONS, AS THE PRECIPITATION PATTERN EVOLVES TO A CANONICAL EL NINO PATTERN.
ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF THE SOUTHERN TIER OF THE
CONUS IN OND 2026 THROUGH MARCH-APRIL-MAY (MAM) 2027. PROBABILITIES FAVORING
ABOVE NORMAL PRECIPITATION EXCEED 60 PERCENT FOR PARTS OF THE SOUTHEAST IN NDJ
2026 THROUGH JFM 2027, WHERE CORRELATIONS OF SEASONAL PRECIPITATION TO ENSO
INDICES ARE GREATEST. BELOW NORMAL PRECIPITATION IS FAVORED FOR PARTS OF THE
MIDWEST IN DJF 2026-27 THROUGH MAM 2027, RELATED TO EL NINO IMPACTS. FAVORED
ABOVE NORMAL PRECIPITATION ALONG THE SOUTH COAST OF MAINLAND ALASKA IN THE
WINTER SEASONS ARE CONSISTENT WITH EL NINO IMPACTS.
FORECASTER: DAN COLLINS
THE CLIMATIC NORMALS ARE BASED ON CONDITIONS BETWEEN 1991 AND 2020, FOLLOWING
THE WORLD METEROLOGICAL ORGANIZATION CONVENTION OF USING THE MOST RECENT 3
COMPLETE DECADES AS THE CLIMATIC REFERENCE PERIOD. THE PROBABILITY ANOMALIES
FOR TEMPERATURE AND PRECIPITATION BASED ON THESE NEW NORMALS BETTER REPRESENT
SHORTER TERM CLIMATIC ANOMALIES THAN THE FORECASTS BASED ON OLDER NORMALS.
FOR A DESCRIPTION OF OF THE STANDARD FORECAST TOOLS - THEIR SKILL- AND THE
FORECAST FORMAT PLEASE SEE OUR WEB PAGE AT
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/PREDICTIONS/LONG_RANGE/TOOLS.HTML
(USE LOWER CASE LETTERS)
INFORMATION ON THE FORMATION OF SKILL OF THE CAS FORECASTS MAY BE FOUND AT:
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/SOILMST_MONITORING/US/OUTLOOK/OUTLOOK.SHTM
L
(USE LOWERCASE LETTERS)
NOTES - THESE CLIMATE OUTLOOKS ARE INTENDED FOR USE PRIOR TO THE START OF THEIR
VALID PERIOD. WITHIN ANY GIVEN VALID PERIOD OBSERVATIONS AND SHORT AND MEDIUM
RANGE FORECASTS SHOULD BE CONSULTED.
THIS SET OF OUTLOOKS WILL BE SUPERSEDED BY THE ISSUANCE OF THE NEW SET NEXT
MONTH ON JUL 16 2026
1991-2020 BASE PERIOD MEANS WERE IMPLEMENTED EFFECTIVE WITH THE MAY 20, 2021
FORECAST RELEASE.
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