696
FXUS05 KWBC 151230
PMD90D
PROGNOSTIC DISCUSSION FOR LONG-LEAD SEASONAL OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830 AM EDT THU MAY 15 2025
SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS
THE EL NIñO SOUTHERN OSCILLATION (ENSO) ALERT SYSTEM STATUS IS CURRENTLY “NOT
ACTIVE” AS ENSO-NEUTRAL CONDITIONS ARE PRESENT. ENSO-NEUTRAL IS FAVORED TO
PERSIST THROUGH SUMMER 2025 WITH CHANCES REACHING 74% DURING JUNE-AUGUST, AND
REMAINING ABOVE 50% THROUGH AUGUST-OCTOBER 2025. ENSO-NEUTRAL CONDITIONS ARE
THUS FORECAST TO BE PRESENT FOR MUCH OF THE SEASONAL OUTLOOK LEADS, AND ARE
HIGHLY LIKELY FOR THE FIRST LEAD, JUNE-JULY-AUGUST (JJA) 2025.
THE JJA 2025 TEMPERATURE AND PRECIPITATION OUTLOOKS ARE QUITE SIMILAR TO LAST
MONTH'S LEAD 2 FORECASTS OF JJA IN TERMS OF OVERALL PATTERN. THE JJA 2025
TEMPERATURE OUTLOOK FAVORS ABOVE NORMAL TEMPERATURES FOR THE ENTIRE CONTIGUOUS
U.S. (CONUS), AND PROBABILITIES ARE ENHANCED OVER THE WEST, FLORIDA, AND THE
NORTHEAST. THE HIGHEST PROBABILITIES, REACHING 70 TO 80%, ARE FOUND OVER THE
INTERIOR WEST AND SOUTHWESTERN TEXAS. OVER ALASKA, SLIGHT CHANGES TO THE
FORECAST FROM LAST MONTH INCLUDE THE INTRODUCTION OF EQUAL CHANCES (EC) OF
ABOVE, NEAR, AND BELOW NORMAL TEMPERATURES OVER PARTS OF THE NORTHERN MAINLAND,
AND PROBABILITIES OF ABOVE NORMAL TEMPERATURES INCREASED TO 40 TO 50% OVER THE
SOUTHERN COAST AND 50 TO 60% OVER SOUTHEASTERN ALASKA.
THE JJA 2025 PRECIPITATION OUTLOOK FAVORS A BROAD REGION OF BELOW NORMAL
PRECIPITATION STRETCHING FROM THE NORTHWEST COAST TO THE UPPER MISSISSIPPI
VALLEY, AS WELL AS PARTS OF THE CENTRAL AND SOUTHERN PLAINS. WITHIN THIS AREA
OF BELOW NORMAL PRECIPITATION, PROBABILITIES REACH 40 TO 50% OVER MUCH OF THE
NORTHERN TIER, AND 50 TO 60% OVER PARTS OF MONTANA. ABOVE NORMAL PRECIPITATION
IS FAVORED OVER THE SOUTHEAST AND ALONG THE EAST COAST TO PARTS OF NEW ENGLAND,
PARTS OF THE SOUTHWEST (MAINLY ARIZONA), AND MUCH OF ALASKA.
EC OF ABOVE, NEAR, AND BELOW NORMAL TEMPERATURES OR PRECIPITATION ARE INDICATED
WHERE THERE IS MODEL AND/OR TOOL DISAGREEMENT, FORECAST PROBABILITIES FOR EACH
CATEGORY ARE SIMILAR, AND TEMPERATURES OR PRECIPITATION ARE EXPECTED TO BE
CLOSE TO THE CLIMATOLOGICAL DISTRIBUTION.
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
FOLLOWING THE RECENT PERIOD OF BELOW AVERAGE SEA SURFACE TEMPERATURES (SSTS) IN
THE CENTRAL PACIFIC, SSTS HAVE BEEN NEAR AVERAGE ACROSS THE CENTRAL AND EASTERN
PACIFIC OCEAN SINCE MID-APRIL. THE MOST RECENT WEEKLY SST DEPARTURES IN THE
NINO3.4 REGION ARE AROUND 0.1 DEGREES CELSIUS (C), WITH SST DEPARTURES IN THE
OTHER NINO REGIONS AROUND -0.1 OR 0 C. IN ADDITION, UPPER OCEAN HEAT ANOMALIES
SIGNIFICANTLY WEAKENED THROUGH FEBRUARY AND MARCH 2025, MAKING WAY FOR THE
RETURN OF NEAR AVERAGE TEMPERATURES IN APRIL 2025. THE NEGATIVE SUBSURFACE
TEMPERATURE ANOMALIES THAT HAD BEEN PRESENT IN THE CENTRAL AND EAST-CENTRAL
PACIFIC OCEAN HAVE WEAKENED AS WELL, AND ABOVE AVERAGE TEMPERATURES REMAIN IN
THE WESTERN AND CENTRAL PACIFIC. OVERALL, THESE SST DEPARTURES AND STATE OF THE
EQUATORIAL PACIFIC REFLECT ENSO NEUTRAL CONDITIONS. THE MADDEN JULIAN
OSCILLATION (MJO) IS FORECAST TO REMAIN WEAK OVER THE NEXT FEW WEEKS AS WELL,
AND AS SUCH NEITHER THE ENSO OR MJO TELECONNECTION ARE STRONGLY CONSIDERED FOR
EARLY LEADS. LOCAL SSTS, INCLUDING ABOVE NORMAL SSTS IN THE GULF OF ALASKA, AND
ALONG THE SOUTHEAST AND EAST COASTS OF THE CONUS, ARE CONSIDERED FOR EARLY
LEADS WHERE APPLICABLE AND RELEVANT.
LOCAL IMPACTS FROM SOIL MOISTURE BECOME MORE OF A PLAYER AS WE SHIFT INTO THE
SPRING. NEGATIVE SOIL MOISTURE ANOMALIES ARE PRESENT OVER THE SOUTHWEST, WITH
STRONG NEGATIVE ANOMALIES FOUND OVER MUCH OF SOUTHWESTERN AND CENTRAL TEXAS.
THERE IS A SHARP GRADIENT TO ABOVE NORMAL SOIL MOISTURE ANOMALIES OVER NORTHERN
TEXAS, PARTS OF THE LOWER AND SOUTHERN MIDDLE MISSISSIPPI VALLEY, TENNESSEE
VALLEY, SOUTHEAST, AND SOUTHERN OHIO VALLEY WHERE THERE HAS BEEN RECENT HEAVY
RAINFALL. BELOW NORMAL SOIL MOISTURE IS ALSO PRESENT OVER PARTS OF THE CENTRAL
AND NORTHERN PLAINS, UPPER MISSISSIPPI VALLEY AND THE NORTHERN PARTS OF THE
MIDDLE MISSISSIPPI AND OHIO VALLEY REGIONS. GIVEN THE WEAKNESS OF ENSO AND MJO,
THE STATE OF ANOMALOUS SOIL MOISTURE IS WEIGHTED MORE HIGHLY THAN
TELECONNECTIONS FOR THIS OUTLOOK, PARTICULARLY FOR THE FIRST LEAD WHERE SOIL
MOISTURE IS EXPECTED TO HAVE MORE OF AN IMPACT.
PROGNOSTIC DISCUSSION OF SST FORECASTS
THOUGH THERE IS SOME SPREAD AMONGST MODELS, SST FORECASTS FROM THE NORTH
AMERICAN MULTI-MODEL ENSEMBLE (NMME) MAINLY FAVOR ENSO-NEUTRAL THROUGH JJA. IN
GENERAL, ENSO-NEUTRAL IS FAVORED TO PERSIST THROUGH THE NORTHERN HEMISPHERE
SUMMER 2025, AND CHANCES OF ENSO-NEUTRAL REMAIN ABOVE 50% THROUGH
AUGUST-OCTOBER (ASO) 2025. FOLLOWING ASO AND INTO DECEMBER-FEBRUARY (DJF) 2025,
CHANCES OF ENSO-NEUTRAL ARE SLIGHTLY FAVORED OVER LA NIñA, AND CHANCES OF EL
NIñO ARE LEAST PROBABLE COMPARATIVELY.
PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS
DYNAMICAL MODEL FORECASTS FROM THE NMME, THE COUPLED FORECAST SYSTEM MODEL
VERSION 2 (CFSV2), AND THE COPERNICUS (C3S) MULTI-MODEL ENSEMBLE SYSTEM WERE
USED EXTENSIVELY FOR THE FIRST SIX LEADS WHEN THEY ARE AVAILABLE, AS WAS THE
OBJECTIVE, HISTORICAL SKILL WEIGHTED CONSOLIDATION AND CALIBRATION, BRIDGING,
AND MERGING (CBAM) GUIDANCE, THAT COMBINES BOTH DYNAMICAL AND STATISTICAL
FORECAST INFORMATION. A CONSOLIDATION OF STATISTICAL TOOLS INCLUDING THE
ENSO-OCN TOOL, WHICH REPRESENTS THE COMBINED INFLUENCE OF ENSO (WHEN ACTIVE)
AND DECADAL TIMESCALE TRENDS IN TEMPERATURE AND PRECIPITATION (UTILIZING THE
OPTIMUM CLIMATE NORMAL, OCN) AND DYNAMICAL MODELS IS USED FOR THE FIRST SIX
LEADS. FOLLOWING THIS, THE ENSO-OCN FORECAST TOOL IS USED MORE EXTENSIVELY. THE
PRESENCE AND FORECAST OF ONGOING ENSO-NEUTRAL CONDITIONS MEANS THAT LONGER
TIMESCALE DECADAL VARIABILITY IN TEMPERATURE AND PRECIPITATION ARE GENERALLY
THE LARGEST PREDICTABLE SIGNAL FOR THE SEASONAL FORECASTS. DECADAL VARIABILITY
AND TRENDS ARE DETERMINED FROM THE OCN, REPRESENTING THE DIFFERENCE BETWEEN THE
MOST RECENT 15-YEAR PERIOD AVERAGE SEASONAL TEMPERATURE OR PRECIPITATION AND
THE AVERAGE FOR THE CLIMATOLOGY PERIOD, FROM 1991-2020.
PROGNOSTIC DISCUSSION OF OUTLOOKS - JJA 2025 TO JJA 2026
TEMPERATURE
THE JJA 2025 TEMPERATURE OUTLOOK FAVORS ABOVE NORMAL TEMPERATURES FOR THE
CONUS. OVERALL THE TEMPERATURE OUTLOOK FOR JJA 2025 IS SIMILAR TO LAST MONTH,
THOUGH MODELS AND TOOLS FAVORED SLIGHT WARMING OVER E.G. THE NORTHERN PLAINS
AND SOUTHWESTERN TEXAS COMPARED TO LAST MONTH. ANY DIFFERENCES OVER CONUS ARE
MINOR, AND ARE MAINLY DUE TO THE SHORTER LEAD OF MODELS AND INFLUENCE FROM
RECENT RAINFALL OR LACK OF RAINFALL ON SOIL MOISTURE WHICH CAN IMPACT THE FIRST
SEASON. GIVEN THE WEAK TELECONNECTIONS FROM ENSO AND MJO, THIS FORECAST MAINLY
RELIES ON DYNAMICAL AND STATISTICAL MODELS, A CONSOLIDATION OF THESE TOOLS, AND
POTENTIAL INFLUENCE FROM SOIL MOISTURE.
PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE ENHANCED OVER THE WEST,
SOUTHWEST, FLORIDA, AND NEW ENGLAND WHERE THERE WAS AGREEMENT AMONG DYNAMICAL
MODELS, INCLUDING NMME AND C3S, AND STATISTICAL TOOLS THAT INCLUDE DECADAL
VARIABILITY. PROBABILITIES REACH 60 TO 70% OVER PARTS OF THE INTERIOR WEST
WHERE DYNAMICAL MODELS SHOWED STRONGER PROBABILITIES, AND OVER SOUTHWESTERN
TEXAS WHERE SOIL MOISTURE IS ANOMALOUSLY LOW. PROBABILITIES REACH 50 TO 60%
OVER NEW ENGLAND AND FLORIDA WHERE COASTAL SSTS AND DECADAL TRENDS ARE ABOVE
NORMAL AS WELL AS HAVING GOOD AGREEMENT AMONG TOOLS. PROBABILITIES ARE STILL
ABOVE NORMAL BUT WEAKER (33-40%) OVER THE NORTHERN PLAINS AND GREAT LAKES
STRETCHING TO THE NORTHERN GULF STATES, WHERE MODEL SKILL IS WEAK (OVER THE
NORTHERN PARTS OF THE REGION) AND WHERE SOIL MOISTURE IS ANOMALOUSLY HIGH (OVER
SOUTHERN PARTS OF THE REGION). THIS MAY LEAD TO A MODERATION OF THE ABOVE
NORMAL TEMPERATURES, THOUGH LIKELY NOT ENOUGH TO TILT PROBABILITIES TOWARD
BELOW NORMAL. MOST OF ALASKA IS AT LEAST WEAKLY FORECAST TO BE ABOVE NORMAL,
WITH MUCH OF THE STATE COVERED WITH 33 TO 40% PROBABILITIES OF ABOVE NORMAL
TEMPERATURES, THOUGH COOLER SSTS AND A COLD SIGNAL IN NMME, C3S, AND CBAM LED
TO FAVORED EC OVER NORTHERN ALASKA. IN CONTRAST, ABOVE NORMAL SSTS, BETTER
MODEL AGREEMENT, AND DECADAL TRENDS ENHANCE THE PROBABILITY OF ABOVE NORMAL
TEMPERATURES OVER THE SOUTHERN COAST AND SOUTHEASTERN PARTS OF THE STATE.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE CONUS AND ALASKA THROUGH ASO
2025, WITH HIGHER PROBABILITIES OVER THE WEST AND NORTHEAST SUPPORTED MAINLY BY
NMME AND C3S FORECASTS AND THE PRESENCE OF DECADAL TRENDS WHICH TILT ODDS MORE
STRONGLY TOWARD ABOVE NORMAL. WHILE MUCH OF THE CONUS REMAINS ABOVE NORMAL IN
SEPTEMBER-NOVEMBER (SON) 2025 THROUGH NOVEMBER-JANUARY (NDJ) 2025, EC IS
INDICATED OVER THE NORTHERN PLAINS BEGINNING IN SON 2025, WHICH THEN EXPANDS TO
THE WEST COAST AND OVER THE WESTERN GREAT LAKES THROUGH NDJ 2026. THIS AREA OF
EC HIGHLIGHTS WHERE SIGNALS ARE WEAKER IN FORECAST TOOLS, MAINLY THE ENSO-OCN
TOOL, AND WHERE DYNAMICAL MODELS HAVE LOWER SKILL AND DISAGREEMENT (THROUGH
LEAD 6). DURING DJF THROUGH FEBRUARY-APRIL (FMA) 2026 SLIGHTLY ENHANCED
PROBABILITIES FOR BELOW-NORMAL TEMPERATURES APPEAR IN PARTS OF THE NORTHWEST
OWING TO THE ENSO-OCN TOOL. THE LONGEST LEAD SEASONAL OUTLOOKS THROUGH JJA 2026
ARE BASED PRIMARILY ON SIGNALS DUE TO DECADAL VARIABILITY AS SHOWN BY THE OCN
TOOL.
PRECIPITATION
THE JJA 2025 PRECIPITATION OUTLOOK IS ALSO SIMILAR TO LAST MONTH'S LEAD 2 JJA
PRECIPITATION OUTLOOK, WITH SOME MODIFICATIONS GIVEN MORE RECENT INFORMATION
AND INITIALIZATION OF MODELS AND TOOLS. BELOW NORMAL PRECIPITATION IS FAVORED
FROM THE WEST COAST TO THE GREAT LAKES, WITH WEAK BELOW NORMAL PROBABILITIES
STRETCHING TO SOUTHWESTERN TEXAS. PROBABILITIES ARE ENHANCED OVER PARTS OF
MONTANA MAINLY DUE TO AGREEMENT AMONG MODELS WHICH INCREASED CONFIDENCE. ABOVE
NORMAL PRECIPITATION IS FORECAST OVER ARIZONA, AS MODELS AND TOOLS DEPICT A
WEAKENING AND WESTWARD SHIFT OF THE ABOVE NORMAL PRECIPITATION COMPARED TO LAST
MONTH, AND THIS AREA OF ABOVE NORMAL PRECIPITATION IS MAINTAINED THROUGH ASO
2025, THOUGH WITH THE MORE WESTWARD ORIENTATION FAVORED BY OUR TOOLS. THE
LIKELIHOOD OF AN ENHANCED SOUTHWEST MONSOON IS WEAKLY INCREASED DUE TO CURRENT
NEGATIVE SOIL MOISTURE ANOMALIES AND PREDICTED ABOVE-NORMAL TEMPERATURES, WHICH
TEND TO BE ANTI-CORRELATED WITH MONSOON PRECIPITATION. ABOVE NORMAL
PRECIPITATION IS ALSO FAVORED FOR THE EAST COAST AND MUCH OF ALASKA FOR JJA
THROUGH SON 2025, AS WELL AS OCTOBER-DECEMBER (OND) 2025 FOR ALASKA, SUPPORTED
BY NMME AND C3S.
IN GENERAL THE PATTERN OF BELOW NORMAL PRECIPITATION OVER PARTS OF THE NORTHERN
CONUS, AND ABOVE NORMAL PRECIPITATION ALONG THE EAST COAST/PARTS OF THE EAST
COAST IS FAVORED OVER THE THROUGH SON 2025. A SHIFT IN THIS SPATIAL PATTERN IS
SEEN BEGINNING IN OND 2025 WHERE BELOW NORMAL PRECIPITATION BECOMES MORE
PROBABLE OVER THE SOUTHWEST, SOUTHEAST, AND SOUTHERN PARTS OF THE EAST COAST,
AND ABOVE NORMAL PRECIPITATION MORE PROBABLE OVER THE NORTHERN PLAINS OR
NORTHWEST AND GREAT LAKES THROUGH SPRING 2026. THE SHIFT FROM ABOVE NORMAL
PRECIPITATION TO BELOW NORMAL PRECIPITATION OVER THE SOUTHEAST FROM SON 2025 TO
NDJ 2025 IS RAPID GIVEN CLIMATOLOGIES OF THESE SEASONS AS WELL AS WEAKER
CHANCES OF AN EL NIñO COMPARED TO NEUTRAL OR LA NIñA CONDITIONS IN FALL AND
WINTER 2025, WHICH LEADS TO MORE LIKELY BELOW NORMAL PRECIPITATION THAN ABOVE
NORMAL. FOLLOWING THIS, THE PATTERN SHIFTS BACK TO A NORTHERN CONUS BELOW
NORMAL PATTERN, WHICH IS PRIMARILY BASED ON THE ENSO-OCN TOOL, THOUGH EC IS
DOMINANT ACROSS THE CONUS GIVEN UNCERTAINTY IN LONGER LEAD FORECASTS. MILD
PROBABILITIES FOR ABOVE NORMAL PRECIPITATION ARE ALSO PRESENT OVER NORTHERN
AND/OR WESTERN ALASKA THROUGHOUT MUCH OF THE LEADS GIVEN RESULTS FROM THE
ENSO-OCN TOOL, SHIFTING TO EC IN APRIL-JUNE (AMJ) 2026 WHEN SIGNALS BECOME TOO
WEAK FOR CONFIDENCE IN PRECIPITATION OVER ALASKA.
FORECASTER: JOHNNA INFANTI
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 JUN 19 2025
1991-2020 BASE PERIOD MEANS WERE IMPLEMENTED EFFECTIVE WITH THE MAY 20, 2021
FORECAST RELEASE.
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