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 DJF 2016
    1.5mn JFM 2017
    2.5mn FMA 2017
    3.5mn MAM 2017
    4.5mn AMJ 2017
    5.5mn MJJ 2017
    6.5mn JJA 2017
    7.5mn JAS 2017
    8.5mn ASO 2017
    9.5mn SON 2017
   10.5mn OND 2017
   11.5mn NDJ 2017
   12.5mn DJF 2017
    0.5mn Dec 2016


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 EST THU NOV 17 2016

SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS

CURRENT OCEANIC AND ATMOSPHERIC CONDITIONS OVER THE TROPICAL PACIFIC ARE
CONSISTENT WITH A WEAK LA NINA EVENT. THE OFFICIAL CPC ENSO FORECAST INDICATES
A 55% CHANCE OF LA NINA (ONI <= -0.5) CONTINUING THROUGH THE DJF WINTER SEASON.
BEYOND THAT, ENSO NEUTRAL CONDITIONS ARE MOST LIKELY HEADING INTO BOREAL
SUMMER, THOUGH THERE IS A SLIGHT TILT TOWARD EL NINO DEVELOPMENT RELATIVE TO
CLIMATOLOGY.

THE DJF 2016-2017 TEMPERATURE OUTLOOK INDICATES INCREASED PROBABILITIES OF
ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE SOUTHERN U.S., NEW ENGLAND, AND
ALASKA.  A SLIGHT TENDENCY TOWARD BELOW-NORMAL TEMPERATURES IS FORECAST OVER
PARTS OF THE UPPER MIDWEST AND NORTHERN PLAINS. THIS OUTLOOK IS INFORMED MOSTLY
BY OBJECTIVE EMPIRICAL GUIDANCE THAT INCORPORATES ENSO, TRENDS, AND OBSERVED
SST EVOLUTION. CALIBRATED DYNAMICAL MODEL GUIDANCE IS ALSO CONSIDERED.

THE DJF 2016-2017 PRECIPITATION OUTLOOK INDICATES INCREASED PROBABILITIES OF
ABOVE-MEDIAN PRECIPITATION FOR PARTS OF THE NORTHERN TIER OF THE U.S., CENTERED
ON THE NORTHERN ROCKIES AND GREAT LAKES. BELOW-MEDIAN PRECIPITATION IS FAVORED
FOR MUCH OF THE SOUTHERN TIER OF THE CONTIGUOUS U.S. WITH THE GREATEST
PROBABILITIES ALONG PARTS OF THE GULF COAST. THE OUTLOOK IS BASED ON A NUMBER
OF FACTORS INCLUDING LA NINA CONSIDERATIONS AND SHORT TERM CLIMATE MODEL
OUTPUT.

EQUAL CHANCES (EC) ARE FORECAST IN AREAS WHERE THE LIKELIHOOD OF SEASONAL MEAN
TEMPERATURES OR SEASONAL ACCUMULATED PRECIPITATION AMOUNTS ARE EXPECTED TO BE
SIMILAR TO CLIMATOLOGICAL PROBABILITIES.

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

IN THE TROPICAL PACIFIC, BOTH OCEANIC AND ATMOSPHERIC OBSERVATIONAL INDICATORS
(ON AVERAGE) INDICATE LA NINA CONDITIONS, THOUGH THE TRADE WINDS REMAIN NEAR
NORMAL ON AVERAGE.

SEA SURFACE TEMPERATURES (SSTS) ALONG THE EQUATOR IN THE PACIFIC BASIN REMAIN
BELOW AVERAGE FROM 180W TO 100W, WHILE SSTS ARE ABOVE AVERAGE ACROSS THE FAR
WESTERN PACIFIC AND IN A HORSESHOE PATTERN NORTH AND SOUTH OF THE AREA OF
COOLER THAN NORMAL SSTS ALONG THE EQUATOR. IN THE NINO-3.4 REGION, THE MOST
RECENT WEEKLY ANOMALY VALUE IS -0.7 DEGREES C WHILE THE MOST RECENT THREE-MONTH
AVERAGE NINO-3.4 SST ANOMALY IS -0.7 DEGREES C FOR THE ASO SEASON. A RESERVOIR
OF ANOMALOUSLY COOL SUBSURFACE WATERS CONTINUES AT DEPTH AND EXTENDS TO MORE
THAN 150 METERS BELOW THE SURFACE, WITH THE LARGEST NEGATIVE ANOMALIES OF 2-4
DEGREES C BELOW AVERAGE FROM 100-150 METERS CENTERED NEAR 140W.

OVER THE PAST SEVERAL WEEKS, ENHANCED CONVECTION HAS BEEN CENTERED OVER THE
MARITIME CONTINENT, WITH SUPPRESSED CONVECTION EXTENDING EASTWARD FROM 160E
ACROSS MUCH OF THE EQUATORIAL PACIFIC. RECENTLY, HOWEVER, SUBSEASONAL
VARIABILITY HAS DISRUPTED THIS PATTERN AND LED TO DRYING ACROSS PARTS OF THE
MARITIME CONTINENT AND EASTERN INDIAN OCEAN. TRADE WINDS OVER THE PAST MONTH
HAVE BEEN NEAR AVERAGE.

SSTS IN THE NORTHEAST PACIFIC AND ALONG THE COAST OF ALASKA REMAIN ABOVE
AVERAGE, ALTHOUGH THE ATMOSPHERIC CIRCULATION HAS FORCED A DRAMATIC COOLING
OVER THE NORTH-CENTRAL PACIFIC BASIN. POSITIVE SST ANOMALIES PERSIST IN THE
WESTERN ATLANTIC NEAR THE U.S. EAST COAST, AND THE GULF OF MEXICO.

PROGNOSTIC DISCUSSION OF SST FORECASTS

THE CPC SST CONSOLIDATION FORECAST, WHICH INCLUDES THREE STATISTICAL FORECASTS
ALONG WITH THE CFS, PREDICTS A WEAK LA NINA DURING DJF 2016-2017 WITH
ENSO-NEUTRAL CONDITIONS FAVORED THEREAFTER. BY WINTER 2017-2018, THE
CONSOLIDATION FAVORS LA NINA OVER EL NINO. THE NORTH AMERICAN MULTI MODEL
ENSEMBLE (NMME) ENSEMBLE MEAN FORECAST FOR THE NINO-3.4 SST ANOMALY IS SLIGHTLY
WARMER THAN LAST MONTH, WITH ENSO-NEUTRAL FAVORED EARLY IN OUTLOOK PERIOD.
BASED ON THE LATEST OBSERVATIONAL AND MODEL FORECAST INDICATORS, THE OFFICIAL
CPC/IRI ENSO OUTLOOK FAVORS LA NINA CONDITIONS AT 55% DURING DJF 2016-2017, THE
SAME PROBABILITY THAT WAS ISSUED LAST MONTH.

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

THE SUBSEQUENT TEMPERATURE AND PRECIPITATION OUTLOOKS CONSIDERED LA NINA
REGRESSIONS, STATISTICAL TOOLS, SUCH AS REGRESSIONS BASED ON THE CPC
CONSOLIDATED SST FORECAST, A CONSTRUCTED ANALOG BASED ON GLOBAL SST ANOMALY
PATTERNS, AND CANONICAL CORRELATION ANALYSIS THAT USES THE EVOLUTION OF SST AND
SEA-LEVEL PRESSURE AS PREDICTORS. ALSO CONSIDERED WERE THE CALIBRATED
PROBABILISTIC FORECASTS FROM THE NMME, GUIDANCE FROM PARTICIPANT MODELS OF THE
INTERNATIONAL MULTI-MODEL ENSEMBLE (IMME) AND THE CPC CONSOLIDATION (CPC CON)
FORECAST. OTHER FACTORS INCLUDED POTENTIAL INFLUENCE FROM MORE LOCAL, COASTAL
SSTS.

PROGNOSTIC DISCUSSION OF OUTLOOKS - DJF 2016 TO DJF 2017

TEMPERATURE

THE TEMPERATURE OUTLOOKS FOR DJF AND JFM REMAIN HIGHLY UNCERTAIN. STATISTICAL
GUIDANCE USING SST-BASED PREDICTORS AND TRENDS HINT TOWARD A COLDER SOLUTION
ACROSS THE NORTHERN CONUS, WHILE DYNAMICAL MODEL GUIDANCE IS NEARLY UNANIMOUS
IN DEPICTING A WARMER-THAN-NORMAL SOLUTION OVER MOST OF NORTH AMERICA. HOWEVER,
HINDCAST EVALUATION REVEALS THAT THE MODEL GUIDANCE HAS LIMITED FORECAST SKILL
FOR THESE SEASONS, AND CALIBRATED GUIDANCE REVEALS SOME SIMILARITIES IN
STRUCTURE TO THE STATISTICAL GUIDANCE. THE OFFICIAL OUTLOOK FAVORS THE
STATISTICAL GUIDANCE, DEPICTING A TILT TOWARD BELOW-NORMAL TEMPERATURES OVER
THE NORTHERN PLAINS AND UPPER MIDWEST. LA NINA REGRESSIONS WOULD TEND TO FAVOR
A COLDER SOLUTION OVER THE NORTHWEST, BUT TRENDS AND BOTH STATISTICAL AND
DYNAMICAL GUIDANCE ARE NOT SUPPORTIVE FOR DJF. BY JFM PROBABILITIES FAVORING
BELOW-NORMAL TEMPERATURES ARE INTRODUCED.

IT IS POSSIBLE THAT LOW-FREQUENCY EXTRATROPICAL VARIABILITY AND SUBSEASONAL
TROPICAL VARIABILITY WILL BE PARTICULARLY IMPORTANT IN DETERMINING THE FINAL
DISTRIBUTION OF TEMPERATURE ANOMALIES OVER NORTH AMERICA. THE ARCTIC
OSCILLATION HAS BEEN IN A FAIRLY PERSISTENT NEGATIVE PHASE SINCE OCTOBER 1, AND
IS FORECAST TO REMAIN GENERALLY NEGATIVE INTO DECEMBER. WHETHER THIS IS A
HARBINGER OF THINGS TO COME THROUGHOUT THE WINTER SEASON IS NOT WELL KNOWN, BUT
THERE IS SOME EVIDENCE TO SUGGEST AN NEGATIVE AO IS MORE LIKELY THIS WINTER.
THIS IN PART LEADS TO VERY LOW PROBABILITIES ACROSS THE EAST COAST, WHERE LA
NINA AND TRENDS WOULD TEND TO FAVOR A SLIGHTLY WARMER OUTCOME. MJO ACTIVITY
COULD ALSO PLAY AN IMPORTANT ROLE. ONE OR TWO STRONG CONVECTIVE EVENTS OVER THE
INDIAN OCEAN COULD FORCE A ROSSBY WAVE RESPONSE THAT WOULD TILT THE WINTER
TOWARD THE WARMER OUTCOME INDICATED BY DYNAMICAL MODELS. HOWEVER, IF ENHANCED
CONVECTION IS CENTERED FARTHER EAST OVER THE MARITIME CONTINENT AND FAR WESTERN
PACIFIC, THE COLDER OUTCOME INDICATED BY STATISTICAL GUIDANCE IS MORE LIKELY
ACROSS THE NORTHERN CONUS.

HEADING INTO LATE WINTER AND EARLY SPRING, BELOW-NORMAL TEMPERATURES ARE
EXPANDED AND SHIFTED WESTWARD TO INCLUDE NORTHERN AREAS OF THE ROCKIES AND
PACIFIC NORTHWEST. BY MAM AND AMJ, THE STATISTICAL AND DYNAMICAL TOOLS COME
INTO BETTER AGREEMENT, DEPICTING PROBABILITIES FAVORING ABOVE-NORMAL
TEMPERATURES OVER THE SOUTHERN, CENTRAL, AND EASTERN CONUS. ABOVE NORMAL
TEMPERATURES REMAIN FAVORED FROM DJF THROUGH AMJ ACROSS THE SOUTHERN TIER OF
THE CONTIGUOUS U.S. WITH THE GREATEST PROBABILITIES OVER THE SOUTHWEST.

THE OUTLOOKS FROM MJJ 2017 AND BEYOND PRIMARILY REFLECT INPUT FROM TRENDS, THE
CCA, AND THE CONSTRUCTED ANALOG BASED ON GLOBAL SST AND FAVOR ABOVE-NORMAL
TEMPERATURES FOR MUCH OF THE CONUS AND ALASKA. TRENDS IN SEA ICE EXTENT
INCREASE PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES FOR THE NORTH SLOPE OF
ALASKA DURING SON AND OND 2017.

BY WINTER 2017-2018, THE OUTLOOK IS MOSTLY INFLUENCED BY TRENDS DUE TO THE
UNCERTAINTY REGARDING ENSO. WHILE LA NINA EVENTS OFTEN OCCUR BACK-TO-BACK, SUCH
AN OUTCOME IS NOT FAVORED AT THIS TIME.

PRECIPITATION

THE DJF 2016-2017 PRECIPITATION OUTLOOK WAS PRIMARILY BASED ON CONSIDERATIONS
OF LA NINA CONDITIONS (REGRESSIONS ANCHORED TO THE CPC SST CONSOLIDATION WITH
TRENDS) AND RELATIVELY CONSISTENT SIGNALS IN CALIBRATED DYNAMICAL MODEL
GUIDANCE FROM THE NMME. ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR NORTHWEST
ALASKA AND PORTIONS OF THE PACIFIC NORTHWEST, NORTHERN ROCKIES, NORTHERN GREAT
PLAINS AND GREAT LAKES. BELOW MEDIAN PRECIPITATION IS FAVORED ACROSS THE
SOUTHERN TIER OF THE CONTIGUOUS U.S. WITH THE GREATEST PROBABILITIES ALONG THE
GULF COAST. IN ADDITION, BELOW-MEDIAN PRECIPITATION IS FAVORED DURING DJF
2016-2017 FOR COASTAL SOUTH-CENTRAL ALASKA SUPPORTED BY LA NINA CONSIDERATIONS
AND DYNAMICAL MODEL GUIDANCE.

THE PRECIPITATION OUTLOOK REMAINS SIMILAR, TO THE FIRST ORDER, THROUGH FMA 2017
WITH A FAVORED ACTIVE NORTHERN STREAM AND WETTER THAN AVERAGE CONDITIONS MOST
LIKELY IN THE AFOREMENTIONED AREAS. COVERAGE FOR ABOVE-MEDIAN PRECIPITATION IS
SLIGHTLY INCREASED IN DJF 2016-17 AND JFM 2017 IN SOME AREAS AS ANY LA NINA
INFLUENCE LIKELY MAY BE MORE PRONOUNCED IN THESE SEASONS AND SIGNALS FROM THE
DYNAMICAL MODEL GUIDANCE ARE SLIGHTLY STRONGER. BELOW-MEDIAN PRECIPITATION
REMAINS FAVORED FOR THE SOUTHERN TIER DURING THESE SEASONS WITH THE LOWEST
COVERAGE AND PROBABILITIES INDICATED IN FMA 2017.

POSITIVE PRECIPITATION TRENDS CONTRIBUTE TO THE OUTLOOK ACROSS SOME AREAS OF
THE NORTHERN PLAINS AND GREAT LAKES BEGINNING IN FMA 2017 AND THIS CONTINUES
THROUGH MJJ 2017. A POSITIVE TREND SIGNAL IS ALSO EVIDENT AND DEPICTED ACROSS
THE NORTHEAST CONUS FROM JJA 2017 THROUGH SON 2017. DRIER THAN AVERAGE
CONDITIONS ARE FAVORED FOR MAM AND AMJ 2017 ACROSS THE SOUTHWEST BASED ON
NEGATIVE HISTORICAL PRECIPITATION TRENDS.

FOR NDJ AND DJF 2017-2018, BELOW-MEDIAN PRECIPITATION IS SLIGHTLY FAVORED OVER
PARTS OF THE FAR SOUTHEASTERN CONUS AND THE WEST COAST CENTERED ON NORTHERN
CALIFORNIA. THESE SIGNALS ARE EVIDENT IN THE VARIOUS STATISTICAL FORECAST TOOLS
AND IS HEAVILY INFLUENCED BY TRENDS.

FORECASTER: STEPHEN BAXTER

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 DEC 15 2016


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