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 FMA 2015
    1.5mn MAM 2015
    2.5mn AMJ 2015
    3.5mn MJJ 2015
    4.5mn JJA 2015
    5.5mn JAS 2015
    6.5mn ASO 2015
    7.5mn SON 2015
    8.5mn OND 2015
    9.5mn NDJ 2015
   10.5mn DJF 2015
   11.5mn JFM 2016
   12.5mn FMA 2016
    0.5mn Feb 2015


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
830AM EST THURSDAY JAN 15 2015

SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS

CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS CONTINUE TO SHOW MIXED SIGNALS
REGARDING THE ENSO STATE. SEA-SURFACE TEMPERATURES (SSTS) REMAINED NEAR TO
ABOVE AVERAGE FOR MOST OF THE EQUATORIAL PACIFIC, BUT THROUGH EARLY JANUARY,
THE ATMOSPHERIC RESPONSE IS NOT ROBUST. TAKEN AS A WHOLE, THE ENSO SYSTEM
REMAINS IN AN ENSO NEUTRAL STATE, WITH SOME ASPECTS OF A WARM EVENT. THE
CHANCES OF EL NINO DEVELOPING DURING THE NEXT 2 MONTHS ARE 50-60 PERCENT, WITH
A RETURN TO ENSO NEUTRAL CONDITIONS FAVORED THEREAFTER.

THE TEMPERATURE OUTLOOK FOR FEBRUARY-APRIL (FMA) 2015 INDICATES ELEVATED
CHANCES OF ABOVE NORMAL MEAN TEMPERATURES ACROSS ALASKA AND THE WESTERN LOWER
48 STATES. INCREASED ODDS FOR BELOW NORMAL MEAN TEMPERATURES ARE INDICATED OVER
PORTIONS OF THE CENTRAL GREAT PLAINS, THE SOUTHERN GREAT PLAINS, AND THE LOWER
MISSISSIPPI RIVER VALLEY.

THE FMA 2015 PRECIPITATION OUTLOOK INDICATES ELEVATED ODDS FOR ABOVE MEDIAN
PRECIPITATION OVER THE SOUTHWEST AND WESTERN PORTIONS OF THE GREAT PLAINS, AS
WELL AS OVER SOUTHERN, COASTAL ALASKA. CHANCES FOR BELOW MEDIAN PRECIPITATION
ARE ELEVATED OVER THE PACIFIC NORTHWEST. INCREASED UNCERTAINTY AND A REDUCED
ROLE OF AN ENSO WARM EVENT OVER THE LOWER 48 STATES PROMPTED A REMOVAL OF AREAS
OF ENHANCED ODDS FOR ABOVE MEDIAN PRECIPITATION OVER THE SOUTHEAST AND BELOW
MEDIAN PRECIPITATION OVER THE GREAT LAKES AND OHIO VALLEY.

IN AREAS WHERE THE LIKELIHOODS OF SEASONAL MEAN TEMPERATURES AND SEASONAL
ACCUMULATED PRECIPITATION AMOUNTS ARE SIMILAR TO CLIMATOLOGICAL PROBABILITIES,
EQUAL CHANCES (EC) IS INDICATED.

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

ATMOSPHERIC AND OCEANIC CONDITIONS ACROSS THE TROPICAL PACIFIC CONTINUE TO
ALIGN, OVERALL, WITH ENSO NEUTRAL CONDITIONS.  POSITIVE SEA SURFACE TEMPERATURE
(SST) ANOMALIES DECREASED ACROSS THE CENTRAL AND EAST-CENTRAL EQUATORIAL
PACIFIC, WITH THE WEEKLY NINO INDICES RANGING FROM +0.8 C IN THE NINO-4 REGION,
TO +0.5 C IN THE NINO-3.4 REGION, TO 0.0 C IN THE NINO-1+2 REGION. THE AREAS
WITH THE LARGEST MAGNITUDE, POSITIVE SST ANOMALIES DURING DECEMBER WERE NEAR
THE DATE LINE AND NEAR 120W. DURING THE FIRST HALF OF JANUARY, ANOMALIES HAVE
GENERALLY DECREASED IN MAGNITUDE. THE EQUATORIAL LOW-LEVEL WINDS WERE LARGELY
NEAR AVERAGE DURING THE MONTH, WHILE UPPER-LEVEL EASTERLY ANOMALIES CONTINUED
IN THE CENTRAL AND EASTERN TROPICAL PACIFIC. ANOMALOUS, ENHANCED CONVECTION WAS
NOTED FARTHER WEST OVER PARTS OF THE MARITIME CONTINENT DURING MOST OF
DECEMBER, ALONG WITH A STRIP OF ENHANCED CONVECTION ALONG 10N, EAST OF THE DATE
LINE. AREAS THAT TYPICAL EXPERIENCE ENHANCED CONVECTION DURING ENSO WARM EVENTS
HAVE NOT EXPERIENCED SUCH CONDITIONS DURING THE PAST COUPLE OF MONTHS. IN
SUMMARY, THE SST ANOMALIES AND SUBSURFACE OCEAN TEMPERATURES ALIGN WITH AN ENSO
WARM EVENT, BUT THE OVERALL ATMOSPHERIC CIRCULATION CONTINUED TO SHOW ONLY
LIMITED COUPLING WITH THE ANOMALOUSLY WARM WATER.

THE PACIFIC DECADAL OSCILLATION (PDO), AS CALCULATED BY THE JOINT INSTITUTE FOR
THE STUDY OF THE ATMOSPHERE AND OCEAN (JISAO), REACHED RECORD LEVELS. THE
DECEMBER PDO VALUE OF +2.51 IS THE LARGEST DECEMBER VALUE ON RECORD (SINCE
1900) AND THE HIGHEST FOR ANY MONTH SINCE AUGUST 1997. THE 2014 OND MEAN INDEX
VALUE OF +1.91 IS THE HIGHEST OND PDO INDEX SINCE 1936.

PROGNOSTIC DISCUSSION OF SST FORECASTS

SSTS OUTLOOKS FOR THE NINO-3.4 REGION GENERALLY INDICATE A CONTINUATION OF
ABOVE AVERAGE TEMPERATURES THROUGH AT LEAST THE NORTHERN HEMISPHERE SUMMER. THE
OUTLOOKS DO HAVE A SLIGHT TREND DOWN, WITH MOST MODELS INDICATING NEAR AVERAGE
(-0.5 TO +0.5 C) SSTS BY AUGUST. THE CFS AND THE COLA CCSM3 ARE NOTABLE
OUTLIERS, WITH THE CFS INDICATING A LARGE WARMING AND THE COLA CCSM3 INDICATING
A DRAMATIC COOLING, THROUGHOUT THE SUMMER.

THE CPC CONSOLIDATION OUTLOOK FOR SSTS INDICATES SMALL MAGNITUDE, POSITIVE
ANOMALIES THROUGH DECEMBER. THE STATISTICAL TOOLS RUN AT CPC ALL DEPICT SMALLER
ANOMALIES THAN THE DYNAMICAL TOOLS, BUT REMAIN ON THE WARM SIDE.

MOST MODELS RUN AS PART OF THE NMME SUITE OF MODELS INDICATE ANOMALIES BETWEEN
+0.5 AND +1.0 C THROUGH JUNE, WITH SPREAD INCREASING QUICKLY BY AUGUST. MOST
ENSEMBLE MEMBERS FROM THE THE NMME MODELS REMAIN ABOVE AVERAGE THROUGH AUGUST.

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

THE PRIMARY TOOLS USED FOR THE OUTLOOKS ARE THE CFS, NMME, IMME, CCA, SMLR, AND
LINEAR REGRESSIONS ON VARIOUS CLIMATE INDICES, INCLUDING THE PDO.  THE EARLY
OUTLOOKS, THROUGH MAM 2015, ARE ALSO INFLUENCED BY THE POTENTIAL FOR IMPACTS OF
A WEAK EL NINO.  THE INFLUENCE OF A POTENTIAL WEAK EL NINO EVENT IS LESS THAN
INDICATED IN LAST MONTHS OUTLOOKS, DUE TO THE CONTINUED WEAK COUPLING OF THE
ATMOSPHERE TO THE EQUATORIAL PACIFIC SSTS. ADDITIONALLY, THE MODELS FROM THE
NMME CONTINUE TO INDICATE THE STRONGEST, ANOMALOUS CONVECTION WEST OF THE DATE
LINE, WITH A SLIGHTLY ENHANCED PACIFIC ITCZ, FURTHER CASTING DOUBT ON THE
EMERGENCE OF AN EL NINO RESPONSE SIMILAR TO COMPOSITES. CONFIDENCE IN THE
DOWNSTREAM SIGNALS OVER THE U.S. IS REDUCED EVEN FURTHER FROM LAST MONTH.

LINEAR REGRESSIONS OF TEMPERATURE AND PRECIPITATION RATE ONTO THE PDO INDEX
PROVIDED ANOTHER INPUT TO THE OUTLOOKS. SIGNALS FROM THAT TOOL GENERALLY
ALIGNED WITH MANY OF THE DYNAMICAL MODELS INCLUDED IN THE NMME.

THE MODELS IN THE NMME EXHIBITED SOME SPREAD, BUT, QUALITATIVELY, NO MORE THAN
IS TYPICAL FOR SEASONAL OUTLOOKS. THE CFS DID INDICATE STRONGER SIGNALS OVER
THE EASTERN HALF OF THE CONUS, BUT THOSE SIGNALS WERE DAMPED OUT WHEN THE CFS
IS COMBINED IN THE NMME AND IMME FRAMEWORK WITH THE OTHER CONSTITUENT MODELS,
INDICATING MORE UNCERTAINTY OVER THE EASTERN CONUS.

PROGNOSTIC DISCUSSION OF OUTLOOKS - FMA 2015 TO FMA 2016

TEMPERATURE

THE FMA 2015 OUTLOOK REFLECTS LESS CERTAINTY FOR IMPACTS ASSOCIATED WITH AN
ENSO WARM EVENT THAN LAST MONTH. ENHANCED PROBABILITIES FOR BELOW AVERAGE
TEMPERATURES ARE INDICATED OVER THE CENTRAL AND SOUTHERN GREAT PLAINS, AND
LOWER MISSISSIPPI VALLEY. REGRESSIONS OF TEMPERATURE ONTO THE PDO INDEX AND A
WEAKNESS IN THE TEMPERATURE FORECAST FIELD FROM THE NMME AND IMME SUPPORT A
SLIGHT EXPANSION OF ENHANCED ODDS OF BELOW NORMAL TEMPERATURES OVER THE CENTRAL
PLAINS. UNCERTAINTY ACROSS THE NORTHEAST PROMPTED THE REMOVAL OF THE AREA OF
ENHANCED ODDS FOR ABOVE AVERAGE TEMPERATURES. OVER ALASKA, MODELS INDICATE
STRONGLY ABOVE AVERAGE TEMPERATURES, CONSISTENT WITH REGRESSIONS OF TEMPERATURE
ON THE PDO INDEX, ABOVE AVERAGE SSTS OVER THE BERING SEA AND GULF OF ALASKA,
AND REDUCED SEA ICE COVERAGE ALREADY OBSERVED.

FOR LEADS 2 AND 3 (MAM AND AMJ 2015), ODDS FOR ABOVE AVERAGE TEMPERATURES WERE
INCREASED OVER THE NORTHERN GREAT PLAINS, ALIGNING WITH PDO BASED REGRESSIONS
AND DYNAMICAL MODEL OUTPUT.  DURING AMJ, THE SIGNAL FOR BELOW AVERAGE
TEMPERATURES ALONG THE RIO GRANDE WAS REMOVED DUE TO INCREASED UNCERTAINTY IN
THE MODELS AND DECREASED RELEVANCE OF TEMPERATURE IMPACTS FROM EL NINO DUE TO
INCREASED UNCERTAINTY IN THE ATMOSPHERIC RESPONSE TO ENSO AND DECREASING SIGNAL
IN TEMPERATURE PATTERNS OVER THE CONUS THROUGH THE SPRING.

THROUGH THE SUMMER MONTHS, THE FORECASTS ALIGN WITH THE CPC CON, WITH AN AREA
OF EC OVER THE CENTER OF THE CONUS. IN THIS REGION, THERE ARE WEAK SIGNALS FROM
THE CON AND CORRELATIONS WITH THE PDO INDEX ARE WEAK.

THROUGH NEXT FALL, THE CPC CON IS HEAVILY FAVORED, WHICH EMPHASIZES TRENDS, AND
ALS THE CA-SST. UNCERTAINTY ABOUT THE PHASE OF ENSO NEXT WINTER PRECLUDES THE
ABILITY TO USE THAT AS A SUBSTANTIAL PREDICTOR FOR NEXT WINTER.  TRENDS IN
TEMPERATURE AND SEA ICE COVERAGE FAVOR ENHANCED ODDS FOR ABOVE AVERAGE
TEMPERATURES THROUGHOUT THE FALL AND WINTER ACROSS NORTHERN ALASKA.

PRECIPITATION

AS WITH TEMPERATURE, THERE IS LESS CERTAINTY ABOUT THE IMPACTS FROM THE ENSO
SYSTEM, SO SOME CHANGES ARE INTRODUCED INTO THE OUTLOOKS. THIS INCREASED
UNCERTAINTY GOING FORWARD LEADS TO MORE SPREAD OVER THE EASTERN CONUS, AND THE
AREAS INDICATING ENHANCED ODDS OF EITHER ABOVE MEDIAN OR BELOW MEDIAN
PRECIPITATION ARE NO LONGER INCLUDED IN THE FMA 2015 OUTLOOK. ODDS FOR ABOVE
MEDIAN PRECIPITATION OVER NORTHERN CALIFORNIA AND NEVADA ARE REDUCED, SO EQUAL
CHANCES IS INDICATED ACROSS THOSE REGIONS. PDO BASED REGRESSIONS OF
PRECIPITATION FAVOR A SLIGHT EXPANSION OF ENHANCED ODDS FOR ABOVE MEDIAN
PRECIPITATION OVER THE CENTRAL GREAT PLAINS, WHICH ALSO PROMPTED A SLIGHT
TRIMMING ON THE EASTWARD SIDE OF THE AREA OF BELOW MEDIAN PRECIPITATION OVER
THE PACIFIC NORTHWEST. A POSITIVE PDO CORRELATES WITH ABOVE MEDIAN
PRECIPITATION OVER THE SOUTHERN COASTAL PORTIONS OF ALASKA. IMME GUIDANCE
SUPPORTS THAT AS WELL, SO IT WAS INCLUDED IN THE OUTLOOK, ALBEIT A SMALLER AREA
THAN THE OUTLOOK ISSUED LAST MONTH.

THROUGH THE SPRING AND EARLY PORTIONS OF THE SUMMER, THE STRONGEST SIGNAL IN
THE MODELS AND REGRESSION TOOLS IS FOR ENHANCED ODDS OF ABOVE MEDIAN
PRECIPITATION OVER THE SOUTHWEST. THE OUTLOOK THERE IS HIGHLY UNCERTAIN,
ESPECIALLY DURING THE APRIL-MAY-JUNE, A CLIMATOLOGICALLY DRY TIME OF YEAR
ACROSS THAT REGION.

TRENDS IN PARTS OF THE SOUTHEAST CONUS INDICATE ELEVATED CHANCES FOR
BELOW-MEDIAN PRECIPITATION AMOUNTS IN DJF AND JFM 2015-16.

FORECASTER: MATTHEW ROSENCRANS

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/90DAY/DISC.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/SOILMST/FORECASTS.HTML (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 FEB 19 2015


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