Skip Navigation Links www.nws.noaa.gov 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center
 
 

CPC Search
About Us
   Our Mission
   Who We Are

Contact Us
   CPC Information
   CPC Web Team

Official 90-day Outlooks are issued once each month near mid-month at 8:30am Eastern Time. Please consult the schedule of 30 & 90-day outlooks for exact release dates.

Text Discussions
   90day Prognostic
   30day Prognostic
   Hawaiian
   Tools


More Outlooks
    0.5mn AMJ 2018
    1.5mn MJJ 2018
    2.5mn JJA 2018
    3.5mn JAS 2018
    4.5mn ASO 2018
    5.5mn SON 2018
    6.5mn OND 2018
    7.5mn NDJ 2018
    8.5mn DJF 2018
    9.5mn JFM 2019
   10.5mn FMA 2019
   11.5mn MAM 2019
   12.5mn AMJ 2019
    0.5mn Apr 2018


Tools Used (see Discussion for explanation)
   CCA
   OCN
   CMP
   SMT
   POE
 
HOME> Outlook Maps>Seasonal Forecast Discussion
 
PROGNOSTIC DISCUSSION FOR LONG-LEAD SEASONAL OUTLOOKS 
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830 AM EDT THU MAR 15 2018

SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS

A LA NINA ADVISORY REMAINS IN EFFECT AS OF EARLY MARCH, REFLECTING THAT
CONDITIONS IN THE OCEAN AND ATMOSPHERE REMAIN CONSISTENT WITH LA NINA, HOWEVER,
THESE CONDITIONS DECAYED CONSIDERABLY IN THE LAST MONTH. ENSO-NEUTRAL
CONDITIONS ARE FORECAST TO RAPIDLY DEVELOP AND ARE LIKELY TO CONTINUE INTO THE
SECOND HALF OF THE YEAR.

THE APRIL-MAY-JUNE (AMJ) 2018 TEMPERATURE OUTLOOK FAVORS ABOVE NORMAL
TEMPERATURES FOR A LARGE AREA STRETCHING FROM CALIFORNIA EASTWARD TO INCLUDE
THE SOUTHWEST, THE SOUTH-CENTRAL PLAINS AND SOUTHEAST AND THEN NORTHWARD TO
ALSO INCLUDE THE EASTERN THIRD OF THE CONTIGUOUS U.S. THE ODDS ARE GREATEST FOR
ABOVE NORMAL TEMPERATURES ACROSS THE SOUTHERN TIER OF THE U.S. THERE IS AN
ENHANCED LIKELIHOOD FOR BELOW NORMAL TEMPERATURES FOR A SMALL REGION CENTERED
IN THE FAR NORTHERN ROCKIES. FOR ALASKA, THE WESTERN AND NORTHERN AREAS OF THE
STATE ARE MOST LIKELY TO OBSERVE ABOVE NORMAL TEMPERATURES DURING AMJ 2018.

FOR PRECIPITATION, BELOW NORMAL PRECIPITATION IS FORECAST DURING AMJ 2018 FROM
THE WEST COAST TO TEXAS AND ALSO FOR A SMALL AREA FOR THE SOUTH COAST OF
ALASKA. WETTER-THAN-NORMAL CONDITIONS ARE HIGHLIGHTED FOR THE NORTHERN
TWO-THIRDS OF ALASKA AND FOR THE NORTHERN PLAINS, GREAT LAKES, NORTHEAST AND
PARTS OF THE OHIO VALLEY AND MID-ATLANTIC.

EQUAL CHANCES (EC) ARE FORECAST IN AREAS WHERE CLIMATOLOGICAL PROBABILITIES ARE
INDICATED FOR SEASONAL MEAN TEMPERATURES AND SEASONAL ACCUMULATED PRECIPITATION
AMOUNTS.

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

EQUATORIAL PACIFIC OCEAN TEMPERATURES REMAIN BELOW AVERAGE FROM NEAR THE DATE
LINE TO JUST WEST OF THE SOUTH AMERICAN COAST WITH THE GREATEST NEGATIVE
DEPARTURES FROM CLIMATOLOGY LOCATED GENERALLY BETWEEN 150 W AND 120 W WITH A
VALUE OF NEAR -1.0 DEGREES C. THE LATEST WEEKLY ANOMALY VALUE OF NINO3.4 IS
-0.7 DEGREES C. OVER THE PAST MONTH, HOWEVER, MUCH OF THE EQUATORIAL PACIFIC
OCEAN TEMPERATURES HAVE WARMED CONSIDERABLY. THE EQUATORIAL UPPER OCEAN HEAT
CONTENT HAS BECOME POSITIVE DURING THE END OF FEBRUARY INTO EARLY MARCH AND
SUBSURFACE TEMPERATURE ANOMALIES INDICATE A ROBUST DOWNWELLING OCEANIC KELVIN
WAVE MOVING EASTWARD WITH TIME AT DEPTH IN THE WEST CENTRAL PACIFIC.

RECENT ATMOSPHERIC CONDITIONS ACROSS THE TROPICAL PACIFIC REMAIN CONSISTENT
WITH LA NINA, BUT HAVE WEAKENED OVER THE PAST MONTH. SUPPRESSED CONVECTION
REMAINED NEAR THE DATE LINE AS DID AREAS OF WEAK ENHANCED CONVECTION OVER THE
MARITIME CONTINENT AND SOUTH PACIFIC CONVERGENCE ZONE. UPPER-LEVEL WINDS AT
200-HPA ARE ANOMALOUSLY WESTERLY OVER MOST OF THE TROPICAL PACIFIC OCEAN.

OTHER FACTORS TO REVIEW INCLUDE SOIL MOISTURE AND SNOWPACK ANOMALIES. POSITIVE
SOIL MOISTURE ANOMALIES ARE EVIDENT IN VICINITY OF THE GREAT LAKES, OHIO VALLEY
SOUTHEASTWARD TO INCLUDE PARTS OF THE LOWER MISSISSIPPI VALLEY. PRECIPITATION
DEFICITS IN PRECEDING MONTHS HAVE RESULTED IN DRIER THAN NORMAL CONDITIONS
ACROSS MUCH OF THE SOUTHERN TIER OF U.S. AND SOME AREAS OF THE CENTRAL PLAINS.
ALSO, ANOMALOUSLY POSITIVE SNOWPACK IS OBSERVED FOR AREAS OF THE FAR NORTHERN
ROCKIES AND HIGH PLAINS.

PROGNOSTIC DISCUSSION OF SST FORECASTS

A REVIEW OF THE LATEST NINO3.4 SST FORECASTS DEPICT A DECAYING LA NINA IN SHORT
ORDER FOLLOWED BY ENSO-NEUTRAL CONDITIONS THROUGH THE BOREAL SUMMER AND IN SOME
CASES INTO THE AUTUMN AND WINTER MONTHS. THE CPC CONSOLIDATION NINO3.4 SST
FORECAST MAINTAINS ENSO-NEUTRAL CONDITIONS THROUGH ITS OUTLOOK PERIOD WHICH
RUNS TO AMJ 2019. THE LATEST AVAILABLE PLUME OF NINO3.4 SST FORECASTS FROM IRI
INDICATES LARGE AND INCREASING SPREAD THROUGH OCT-NOV-DEC (OND) 2018. THE
STATISTICAL MODEL FORECAST AVERAGE MAINTAINS ENSO-NEUTRAL CONDITIONS THROUGH
THIS OND 2018 PERIOD WHILE THE DYNAMICAL MODEL AVERAGE INCREASES NINO3.4 SSTS
SLIGHTLY MORE RAPIDLY DURING THE SUMMER AND ENTERS WEAK EL NINO TERRITORY
(NINO3.4 ANOMALY GREATER THAN 0.5 DEGREES C) NEAR OR BY OND 2018. AN
INTERESTING OUTLIER TO THIS, IS THE CFS WHICH MAINTAINS LA NINA OR NEAR LA NINA
CONDITIONS THROUGH OND 2018 WITH LARGE SPREAD. MOST OF THE REMAINING MODELS
FROM THE NMME SUITE MIMIC SIMILAR BEHAVIOR AS THAT SHOWN BY THE IRI DYNAMICAL
MODEL AVERAGE.

PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS

ALTHOUGH LA NINA IS WEAKENING IN ITS REPRESENTATION IN BOTH THE OCEAN AND
ATMOSPHERE, LA NINA AND ITS ASSOCIATED FOOTPRINT FROM WINTER TEMPERATURE AND
PRECIPITATION ANOMALIES ARE STILL CONSIDERED IN PREPARATION OF THE AMJ 2018
OUTLOOK. THESE FOOTPRINTS INCLUDE ANOMALOUS SOIL MOISTURE AND SNOWPACK IN SOME
AREAS OF THE CONTIGUOUS UNITED STATES. A HOST OF BOTH STATISTICAL AND DYNAMICAL
MODEL OBJECTIVE FORECAST TOOLS WERE ALSO UTILIZED. SOME PRIMARY INPUTS FROM
THIS LIST INCLUDED A BASELINE TOOL COMBINING THE INFLUENCES OF ENSO AND DECADAL
TEMPERATURE TRENDS (TEMPERATURE ONLY) ANCHORED TO THE CPC NINO3.4 SST
CONSOLIDATION FORECAST THROUGHOUT THIS ENTIRE OUTLOOK PERIOD (AMJ 2019), LONG
TERM TRENDS (OCN) DIRECTLY, AS WELL AS BIAS-CORRECTED, CALIBRATED MODEL OUTPUT
FROM THE NMME SUITE OF DYNAMICAL MODELS.

PROGNOSTIC DISCUSSION OF OUTLOOKS - AMJ 2018 TO AMJ 2019

TEMPERATURE

THE MAJORITY OF THE COUNTRY IS FAVORED TO SEE ABOVE NORMAL TEMPERATURES DURING
THE AMJ 2018 PERIOD. THIS INCLUDES PORTIONS OF NORTHERN AND WESTERN ALASKA AND
MOST OF THE CONTIGUOUS U.S. EXCEPT AREAS OF THE NORTHERN ROCKIES WHICH IS THE
ONLY REGION LEANING TOWARD BELOW NORMAL TEMPERATURES THIS SPRING. A NUMBER OF
FACTORS LEAD TO THE AMJ 2018 FORECAST AND INCLUDE WEAK AND/OR RESIDUAL LA NINA
IMPACTS, SIGNALS FROM BOTH OBJECTIVE STATISTICAL AND DYNAMICAL MODEL FORECAST
GUIDANCE AND DECADAL TEMPERATURE TRENDS. THE GREATEST CONFIDENCE IN THE AMJ
2018 OUTLOOK IS ACROSS THE SOUTHERN TIER WHERE INFLUENCES FROM LA NINA,
OVERWHELMING CONSISTENCY IN DYNAMICAL MODEL GUIDANCE AND STATISTICAL TOOLS,
LONG TERM TRENDS, SOIL MOISTURE DEFICITS ALL COINCIDED AND FAVOR WARMER THAN
NORMAL CONDITIONS. THE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE TEMPERED
SOMEWHAT (ALTHOUGH STILL REFLECT ENHANCED ODDS FOR ABOVE NORMAL TEMPERATURES)
FOR SOME AREAS IN THE GREAT LAKES, OHIO VALLEY AND TENNESSEE VALLEY DUE TO
POSITIVE SOIL MOISTURE DEPARTURES FROM RECENT HEAVY PRECIPITATION WHICH MAY
HAVE A LINGERING COOLING IMPACT THAT SOMEWHAT DECREASES THE ODDS OF WARMER THAN
NORMAL CONDITIONS. ANOMALOUS SNOWPACK AND SUPPORT FROM STATISTICAL FORECAST
GUIDANCE FAVOR THE RELATIVELY SMALL REGION OF BELOW NORMAL TEMPERATURES IN THE
FAR NORTHERN ROCKIES. ANOMALOUSLY WARMER THAN AVERAGE AND OPEN WATERS IN
PROXIMITY TO COASTAL AREAS OF ALASKA FAVOR ABOVE NORMAL TEMPERATURES THERE IN
ADDITION TO OTHER FORECAST GUIDANCE.

THE GENERAL THEME OF THE DEPICTION AND EVOLUTION OF THE TEMPERATURE OUTLOOKS
WITH THIS FORECAST PACKAGE FOLLOWED IN GENERAL TERMS THE BASELINE GUIDANCE THAT
OBJECTIVELY COMBINES ENSO AND DECADAL TEMPERATURE TRENDS KEYED TO THE CPC
NINO3.4 SST CONSOLIDATION FORECAST. THIS APPROACH IS ADJUSTED AND REINFORCED
WHERE NECESSARY AT EARLY LEADS MY THE NMME DYNAMICAL MODEL BIAS CORRECTED,
CALIBRATED FORECAST GUIDANCE.

ENSO-NEUTRAL CONDITIONS ARE FAVORED THROUGH THE SUMMER MONTHS INTO THE AUTUMN
2018 SO TRENDS AND NMME FORECAST GUIDANCE PLAYED THE LARGEST ROLES IN THE
OUTLOOKS THROUGH AUG-SEP-OCT (ASO) 2018. MOST OF THE COUNTRY LEANS TOWARD ABOVE
NORMAL TEMPERATURES THROUGH THIS PERIOD WITH THE GREATEST ODDS PRIMARILY
LOCATED ACROSS THE WESTERN THIRD OF THE CONTIGUOUS U.S. AND ALONG THE EASTERN
SEABOARD, ESPECIALLY THE NORTHEAST. STATISTICAL FORECAST GUIDANCE AND WEAK
TEMPERATURE TRENDS TEND TO FOCUS ON THE INTERIOR CENTRAL U.S. AS A LOCATION
WITH THE GREATEST UNCERTAINTY IN THE EVENTUAL CATEGORY OF SEASONAL MEAN
TEMPERATURES BY JUL-AUG-SEP (JAS) AND ASO 2018.

THE TEMPERATURE OUTLOOKS THROUGH NOV-DEC-JAN (NDJ) 2018-2019 GENERALLY REMAINED
UNCHANGED FROM THE PREVIOUS RELEASED PACKAGE IN MID-FEBRUARY.

THE LARGE SPREAD IN THE FORECAST PHASE OF ENSO BY NDJ 2018-2019 CONSIDERABLY
INCREASES THE UNCERTAINTY IN EVENTUAL IMPACTS IN KEY AREAS WHERE TEMPERATURE
TRENDS ARE LESS OF A FACTOR. CONSEQUENTLY, A LARGER AREA OF EQUAL CHANCES (EC)
IS HIGHLIGHTED ON THE OUTLOOK MAP FROM THE PREVIOUS FORECAST PACKAGE FOR
DEC-JAN-FEB (DJF) 2018-2019 AND JAN-FEB-MAR (JFM) 2019 IN A CORRIDOR FROM THE
NORTHERN PLAINS TO THE SOUTHEAST. DECADAL TEMPERATURE TRENDS DOMINATE THE
REMAINDER OF THE OUTLOOKS THROUGH AMJ 2019.

PRECIPITATION

THE AMJ 2018 PRECIPITATION OUTLOOK HIGHLIGHTS ANTICIPATED DRIER-THAN-NORMAL
CONDITIONS FROM THE WEST COAST SOUTHEASTWARD TO TEXAS AND PROSPECTS FOR ABOVE
NORMAL PRECIPITATION FOR A REGION GENERALLY CENTERED ACROSS THE GREAT LAKES BUT
EXTENDING BOTH EAST AND WEST TO THE NORTHEAST AND NORTHERN PLAINS RESPECTIVELY.
BOTH AREAS SHOW MODEST PROBABILITIES AND SO DEPICT ONLY MODERATE CONFIDENCE.
BOTH AREAS IN LARGE EXTENT ARE SUPPORTED BY RESIDUAL LA NINA CONDITIONS DURING
THE EARLY PORTION OF THE AMJ 2018 OUTLOOK PERIOD. BELOW NORMAL PRECIPITATION IN
THE SOUTHWEST QUARTER OF THE CONTIGUOUS U.S. IS ALSO SUPPORTED BY NMME
DYNAMICAL MODEL GUIDANCE WHILE WETTER-THAN NORMAL CONDITIONS HIGHLIGHTED ARE
CONSISTENT WITH LONG TERM PRECIPITATION TRENDS. FOR ALASKA, THE ENHANCED
LIKELIHOOD FOR BELOW- (ABOVE-NORMAL) PRECIPITATION DEPICTED ARE PRIMARILY
SUPPORTED BY A RESIDUAL LA NINA INFLUENCE AND STATISTICAL FORECAST GUIDANCE.

THEREAFTER, THE OUTLOOKS FROM ASO 2018 ARE PRIMARILY BASED ON A COMBINATION OF
NMME MODEL GUIDANCE AND LONG TERM PRECIPITATION TRENDS AS THE EXPECTATION OF
ENSO NEUTRAL CONDITIONS WILL PREVAIL THROUGHOUT THIS PERIOD. UTILIZING THIS
APPROACH, THE OUTLOOKS DEPICT AREAS WHERE BELOW NORMAL PRECIPITATION IS FAVORED
IN AMJ 2018 TO GENERALLY MOVE NORTHWARD AND DECREASE IN COVERAGE BY JAS 2018.
AREAS FAVORED TO RECEIVE ABOVE NORMAL PRECIPITATION ALSO DECREASE IN COVERAGE
AND LATER FOCUS ALONG THE ATLANTIC SEABOARD BY ASO 2018.

DUE TO BELOW NORMAL SNOWPACK AND DRY CONDITIONS IN GENERAL ALONG WITH SOME
MODEST DYNAMICAL MODEL GUIDANCE SUPPORT, ABOVE NORMAL PRECIPITATION WAS
STRONGLY CONSIDERED FOR THE MONSOON SEASON IN THE SOUTHWEST U.S. AND CENTRAL
ROCKIES DURING JAS AND ASO 2018. BUT GIVEN THE LARGE RANGE IN SOLUTIONS AND
FORECAST TOOLS AT THE CURRENT TIME, THIS OUTLOOK MAINTAINS EQUAL CHANCES (EC)
AS THE FORECAST IN THIS REGION AND SEASON AT THIS TIME.

STATISTICAL FORECAST GUIDANCE AND LONG TERM PRECIPITATION TRENDS ARE NOT STRONG
AND CONSISTENT FOR MUCH OF THE REMAINDER OF THE OUTLOOK PACKAGE AND SO EQUAL
CHANCES ARE INDICATED AT THESE LEAD TIMES. ALTHOUGH SOME WEAK SIGNALS ARE
INDICATED IN THE WINTER SEASONS, THEY CURRENTLY OPPOSE THE MOST LIKELY PHASES
OF ENSO (EL NINO OR ENSO-NEUTRAL) CURRENTLY BEING FORECAST AT THIS OUTLOOK TIME
RANGE.

FORECASTER: JON GOTTSCHALCK

THE CLIMATIC NORMALS ARE BASED ON CONDITIONS BETWEEN 1981 AND 2010, 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 APR 19 2018


1981-2010 BASE PERIOD MEANS WERE IMPLEMENTED EFFECTIVE WITH THE MAY 19, 2011
FORECAST RELEASE.
$$

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5200 Auth Road
Camp Springs, Maryland 20746
Climate Prediction Center Web Team
Page last modified: January 17, 2006
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act
About Us
Career Opportunities