Tag Archives: Winter 2014-2015

Official Prediction of US Winter

The National Oceanic and Atmospheric Administration (NOAA) has released its official prediction of what this winter is going to be like.

And yes, it is in ALL CAPS!!! I’ve pasted it below, but first a summary of the relevant points.

According to NOAA

El Nino

<li>There will be a weak El Nino, late Autumn or Winter.</li>

<li>Or, there could be a moderate EL Nino.</li>

<li>Or, there could just be this thing that might someday be an El Nino but doesn't quite do that for an indefinate period of time.</li>

November, December, January Temps

  • Warmer along the West and Northwest, all the Northern State and New England, and the Atlantic Seaboard.
  • Colder than average in places that are usually warm (from E. New Mexico to the Western Gulf States.
  • November, December, Janurary Precipitation

  • Mostly, pretty near average.
  • More rain than average from California east and pretty much everywhere but the Pacific Northwest, Great Lakes and Ohio Valley (which will be slightly below normal)
  • Temperature Outlook Graphic

    Outlook_map_temp2014F

    Precipitation Outlook Graphic

    Outlook_map_Precip_214F

    The Movie

    The actual findings in ALL CAPS

    PROGNOSTIC DISCUSSION FOR LONG-LEAD SEASONAL OUTLOOKS
    NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
    830AM EDT THURSDAY OCT 16 2014

    SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS

    THE MAIN FACTORS THAT USUALLY INFLUENCE THE SEASONAL CLIMATE OUTLOOK INCLUDE:
    1) EL NINO AND LA NINA – WHICH TOGETHER COMPRISE EL NINO/SOUTHERN OSCILLATION
    OR ENSO. IMPACTS OF THESE EVENTS ARE SUMMARIZED BY SEPARATING 3-MONTH
    OBSERVATIONS FROM 3 OR MORE DECADES INTO EL NINO, NEUTRAL, AND LA NINA SETS,
    AVERAGING EACH SEPARATELY, AND THEN COMPUTING ANOMALIES. THESE ARE CALLED “ENSO
    COMPOSITES”, WHICH ARE USED AT TIMES TO SUBJECTIVELY MODIFY THE FORECAST.
    2) TRENDS – APPROXIMATED BY THE OCN TOOL AS THE DIFFERENCE BETWEEN THE MOST
    RECENT 10-YEAR MEAN OF TEMPERATURE OR 15-YEAR MEAN OF PRECIPITATION FOR A GIVEN
    LOCATION AND TIME OF YEAR AND THE 30-YEAR CLIMATOLOGICAL PERIOD (1981-2010).
    3) THE MADDEN-JULIAN OSCILLATION (MJO) – AFFECTS CLIMATE VARIABILITY WITHIN
    SEASONS.
    4) THE NORTH ATLANTIC OSCILLATION (NAO) AND THE PACIFIC – NORTH AMERICAN (PNA)
    PATTERNS – WHICH AFFECT ANOMALY PATTERNS ESPECIALLY DURING THE COLD SEASONS.
    THESE PHENOMENA ARE CONSIDERABLY LESS PREDICTABLE ON A SEASONAL TIMESCALE THAN
    ENSO.
    5) THE PACIFIC DECADAL OSCILLATION (PDO) – AN ENSO-LIKE PATTERN OF CLIMATE
    VARIABILITY AFFECTING THE TROPICS AND THE NORTH PACIFIC AND NORTH AMERICAN
    REGIONS, BUT WHICH VARIES ON A MUCH LONGER TIMESCALE THAN ENSO.
    6) PERSISTENTLY DRY OR WET SOILS IN THE SPRING AND SUMMER AND SNOW AND ICE
    COVER ANOMALIES IN THE WINTER. THESE FACTORS TEND TO PERSIST FOR LONG PERIODS
    AND ACT AS A KIND OF MEMORY IN THE CLIMATE SYSTEM.
    7) STATISTICAL FORECAST TOOLS – CANONICAL CORRELATION ANALYSIS (CCA), SCREENING
    MULTIPLE LINEAR REGRESSION (SMLR), CONSTRUCTED ANALOGUE (CA) AND ENSEMBLE CCA
    (ECCA).
    8) DYNAMICAL FORECAST MODELS – INCLUDING THE NCEP CLIMATE FORECAST SYSTEM
    (CFS). AN EXPERIMENTAL MODEL FORECAST SYSTEM, THE NORTH AMERICAN MULTI-MODEL
    ENSEMBLE, COMPRISED OF SEVERAL MODELS AND DESIGNATED NMME, MAY ALSO BE USED
    EXPERIMENTALLY AND SUBJECTIVELY UNTIL IT IS INCLUDED INTO THE CONSOLIDATION. AN
    INTERNATIONAL MULTI-MODEL ENSEMBLE DESIGNATED IMME IS ALSO AVAILABLE.
    9) CONSOLIDATION (CON) – AN OBJECTIVE, SKILL-WEIGHTED COMBINATION OF THE OCN,
    CCA, SMLR, ECCA, AND CFS FORECASTS IS USED AS A FIRST GUESS IN PREPARING THE
    FORECAST MAPS. THIS TECHNIQUE MAKES OPTIMUM USE OF THE KNOWN SKILL OF FORECAST
    TOOLS.

    CURRENT ATMOSPHERIC AND OCEANIC OBSERVATIONS ARE CONSISTENT WITH ENSO-NEUTRAL
    CONDITIONS WITH A STILL FAVORED TRANSITION TO EL NINO CONDITIONS IN LATE AUTUMN
    AND WINTER. A WEAK EL NINO EVENT IS MOST PROBABLE, HOWEVER THERE REMAINS A
    CHANCE OF EITHER A LOW-END MODERATE EVENT OR CONTINUED ENSO-NEUTRAL CONDITIONS
    DURING THE UPCOMING OUTLOOK PERIOD.

    THE TEMPERATURE OUTLOOK FOR NOVEMBER-DECEMBER-JANUARY (NDJ) 2014-15 INDICATES
    ELEVATED PROBABILITIES OF ABOVE-NORMAL MEAN TEMPERATURES FOR ALASKA, THE FAR
    WEST, ALONG THE NORTHERN TIER OF THE CONTINENTAL U.S. EASTWARD TO INCLUDE PARTS
    OF THE NORTHEAST AND MID-ATLANTIC. BELOW-NORMAL MEAN TEMPERATURES ARE MOST
    LIKELY OVER AREAS FROM EASTERN NEW MEXICO TO THE WESTERN GULF COAST STATES.

    THE NDJ 2014-15 PRECIPITATION OUTLOOK INDICATES ENHANCED PROBABILITIES OF
    BELOW-MEDIAN PRECIPITATION FOR PARTS OF THE PACIFIC NORTHWEST, NORTHERN
    ROCKIES, GREAT LAKES AND OHIO VALLEY. INCREASED PROBABILITIES FOR ABOVE-MEDIAN
    PRECIPITATION AMOUNTS ARE FORECAST FROM SOUTHERN CALIFORNIA EASTWARD ACROSS THE
    SOUTHWEST, SOUTHERN PLAINS, AND ALONG THE GULF AND SOUTHERN ATLANTIC COASTS
    NORTHWARD TO INCLUDE THE EASTERN SEABOARD TO SOUTHERN NEW ENGLAND. THE
    PROBABILITIES FOR ABOVE-MEDIAN PRECIPITATION ARE ALSO ENHANCED OVER PARTS OF
    SOUTHERN ALASKA.

    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 IN THE TROPICAL PACIFIC REMAIN MOST
    CONSISTENT WITH AN ENSO-NEUTRAL STATE, WHILE CONTINUING TO SHOW SOME INDICATORS
    FOR POTENTIAL DEVELOPMENT OF AN EL NINO. OBSERVATIONS DURING THE SECOND WEEK OF
    OCTOBER SHOW POSITIVE SST DEPARTURES ACROSS THE ENTIRE EQUATORIAL PACIFIC
    BASIN, WITH GREATER THAN +0.5C ANOMALIES IN THE EAST-CENTRAL PACIFIC AND FAR
    WESTERN PACIFIC. WITHIN THESE AREAS THERE ARE ANOMALIES GREATER THAN +1.0C. THE
    NINO3.4 REGION CONTINUES TO HOVER NEAR +0.4C WITH VALUES OF +0.5C FOR NINO4,
    +0.6C IN NINO3, AND +0.6C IN NINO1+2. SST ANOMALIES INCREASED IN THE
    EAST-CENTRAL PACIFIC DURING THE LAST MONTH. OCEAN SUBSURFACE TEMPERATURE
    ANOMALIES CONTINUE TO SHOW POSITIVE VALUES RANGING FROM +1.0C TO +3.0C FROM THE
    SURFACE TO A DEPTH OF ABOUT 125 METERS ACROSS THE EAST-CENTRAL PACIFIC.
    MOREOVER, POSITIVE ANOMALIES ARE ALSO EVIDENT AT A DEPTH FROM 100 – 200 METERS
    NEAR AND JUST WEST OF THE DATE LINE.

    MONTHLY AVERAGED OLR ANOMALIES REMAIN MIXED ACROSS THE EQUATORIAL PACIFIC WITH
    THE GREATEST ANOMALIES AWAY FROM THE DATE LINE WITH TWO AREAS OFF OF THE
    EQUATOR SHOWING ENHANCED CONVECTION OVER THE FAR WESTERN PACIFIC. MONTHLY
    AVERAGED LOW- AND UPPER-LEVEL WINDS REMAIN NEAR AVERAGE, INDICATING THAT THE
    ATMOSPHERE CONTINUES TO STRUGGLE TO RESPOND OVER THE PACIFIC TO ABOVE AVERAGE
    SSTS.

    PERSISTENT, STRONGLY POSITIVE SST ANOMALIES WERE OBSERVED IN THE NORTH PACIFIC,
    ALONG THE PACIFIC COAST OF NORTH AMERICA, AND WESTWARD ACROSS THE SUBTROPICAL
    PACIFIC OCEAN. THIS SST PATTERN PROJECTS WEAKLY ONTO A POSITIVE PDO. POSITIVE
    SST ANOMALIES WERE ALSO OBSERVED ALONG THE ATLANTIC COAST. IN ADDITION,
    ANOMALOUS SNOW COVER EXTENT HAS ALSO INCREASED IN RECENT WEEKS ACROSS PORTIONS
    OF EURASIA AND IS BEING MONITORED.

    PROGNOSTIC DISCUSSION OF SST FORECASTS

    MOST STATISTICAL AND DYNAMICAL MODELS CONTINUE TO PREDICT THAT AN EL NINO EVENT
    WILL DEVELOP WITHIN AUTUMN AND PEAK (AS DEFINED BY NINO3.4 ANOMALIES) AS A WEAK
    EVENT DURING THE WINTER IN MANY FORECASTS AND ALSO ON AVERAGE. THE SPREAD
    REMAINS SOMEWHAT LARGE AS SOME TOOLS PREDICT CONTINUATION OF NINO3.4 ANOMALIES
    BELOW +0.5C WHILE SOME DYNAMICAL MODELS CONTINUE TO INDICATE A MODERATE EVENT
    WITH FORECAST ANOMALIES OF GREATER +1.0C. OVERALL THIS MONTH CONTINUES THE
    SLIGHT TREND SEEN OVER THE PAST FEW MONTHS OF DECREASING NINO3.4 POSITIVE
    ANOMALIES IN THE MODEL GUIDANCE. AN INTERESTING POINT THIS MONTH IS ALSO THAT
    THE DYNAMICAL MODELS PEAK ANY EL NINO EVENT LATER IN THE WINTER, WHICH WOULD BE
    SOMEWHAT UNUSUAL. WHILE FEW ENSO EVENTS HAVE DEVELOPED AT THIS TIME OF YEAR, IT
    IS NOT UNPRECEDENTED, AND CONSIDERED TOGETHER, MODEL FORECASTS AND CURRENT
    OBSERVATIONS CONTINUE TO SUPPORT THE CONSENSUS ENSO FORECAST INDICATING A
    60-65% CHANCE OF EL NINO DEVELOPMENT IN LATE AUTUMN OR WINTER AND THE OFFICIAL
    TEMPERATURE AND PRECIPITATION OUTLOOKS CONTINUE TO CONSIDER EL NINO IMPACTS AT
    THIS TIME.

    POSITIVE NORTH PACIFIC AND WESTERN ATLANTIC SST ANOMALIES ARE FORECAST TO
    PERSIST IN SEASONAL AVERAGES THROUGH THE BOREAL WINTER BY MANY DYNAMICAL MODELS
    INCLUDING THE NMME AND IMME, ALONG WITH THE FORECAST OF EL NINO DEVELOPMENT.
    THESE SUB-TROPICAL AND HIGHER LATITUDE SST ANOMALIES ARE ALSO CONSIDERED IN THE
    OUTLOOK AND LIKELY TO IMPACT THE CLIMATE OF NORTH AMERICA IN THE NEXT SEVERAL
    SEASONS.

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

    THE TEMPERATURE AND PRECIPITATION OUTLOOKS CONTINUE TO BE INFLUENCED BY
    POTENTIAL IMPACTS OF A WEAK EL NINO BEGINNING WITH NDJ 2014-15 AND CONTINUING
    PRIMARILY THROUGH FMA 2015, ALTHOUGH LESS SO THAN PREVIOUS OUTLOOKS FOR SOME
    AREAS IN THE TEMPERATURE OUTLOOKS. SST ANOMALIES IN OTHER AREAS OUTSIDE THE
    EQUATORIAL PACIFIC WERE UTILIZED OR CONSIDERED, INCLUDING BUT NOT LIMITED TO
    COASTAL AREAS NEAR THE WEST COAST, IN PROXIMITY TO ALASKA AND AREAS ALONG THE
    U.S. EAST COAST.

    THE CONSTRUCTED ANALOG FORECAST FOR TEMPERATURE AND PRECIPITATION BASED ON
    GLOBAL SST PATTERNS WAS ALSO UTILIZED IN THE OUTLOOKS AS WAS INFORMATION FROM A
    LARGE VARIETY OF DYNAMICAL MODEL GUIDANCE, INCLUDING THE CFS, THE NMME AND IMME
    AND THEIR PARTICIPANT MODELS, WITH ADJUSTMENTS MADE FOR POTENTIAL MODEL BIASES.
    THE SHIFT IN PROBABILITIES RELATED TO POSITIVE NINO3.4 ANOMALIES IN THE RANGE
    OF 0.5C TO 1.0C WERE CONSIDERED. ALTHOUGH CHANGES AND EXTENT OF SNOW COVER
    ACROSS EURASIA AND ANY ASSOCIATED TELECONNECTIONS GENERALLY REQUIRE COMPLETION
    OF THE MONTH OF OCTOBER, IT WAS CONSIDERED IN FORMULATING THE OUTLOOK.

    FOR OUTLOOKS FROM AMJ THROUGH OND 2015, DECADAL TRENDS DUE TO CHANGES IN THE
    CLIMATE BASE STATE AND THE CON (HEAVILY INFLUENCED BY TRENDS) ARE THE PRIMARY
    SOURCE OF TEMPERATURE AND PRECIPITATION SIGNALS.

    PROGNOSTIC DISCUSSION OF OUTLOOKS – NDJ 2014 TO NDJ 2015

    TEMPERATURE

    THE SET OF OUTLOOKS THIS MONTH DEPICT A SOMEWHAT COOLER SCENARIO FOR THE FIRST
    FEW LEADS (THROUGH FMA 2015) AS COMPARED TO THE PREVIOUS SET OF OUTLOOKS. MORE
    SPECIFICALLY AND BETTER STATED, COVERAGE AND PROBABILITIES FOR ABOVE NORMAL
    TEMPERATURES WERE REDUCED OR REMOVED ACROSS NORTHERN AREAS OF THE EASTERN CONUS
    AND PROBABILITIES FOR BELOW NORMAL TEMPERATURES INCREASED IN COVERAGE FOR
    PORTIONS OF THE LOWER-TO-CENTRAL MISSISSIPPI VALLEY, TENNESSEE VALLEY,
    SOUTHEAST AND LOWER MID-ATLANTIC. THIS IS BASED ON AN INCREASED LIKELIHOOD OF
    ANY EL NINO EVENT BEING OF WEAK MAGNITUDE, CONSIDERABLE CHANGE IN MUCH OF THE
    DYNAMICAL MODEL GUIDANCE (OTHER THAN THE CFS) AND INDICATIONS IN SOME TOOLS AND
    INFORMATION FOR A POTENTIAL TENDENCY TOWARD A NEGATIVE AO AND NAO DURING THE
    WINTER MONTHS.

    POTENTIAL EL NINO CONDITIONS CONTRIBUTE TO THE OUTLOOKS PRIMARILY THROUGH FMA
    2015. FOR NDJ AND DJF 2014-15, ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS
    ALASKA, THE FAR WEST AND ALONG THE NORTHERN TIER OF THE CONUS EASTWARD TO
    INCLUDE PARTS OF THE NORTHEAST AND MID-ATLANTIC (NDJ ONLY). THE PROBABILITIES
    FOR ABOVE-NORMAL TEMPERATURES ARE REDUCED AND SHIFTED SOMEWHAT NORTHWARD IN DJF
    FOR BOTH THE GREAT LAKES AND NORTHEAST. THE HIGHEST ODDS ARE FOR COASTAL AREAS
    ALONG THE WEST COAST AND PARTS OF SOUTHERN ALASKA WHERE SST ANOMALIES ARE
    CONSIDERABLY ABOVE AVERAGE AND LIKELY WILL INFLUENCE TEMPERATURES FOR NDJ
    2014-15. ABOVE-NORMAL TEMPERATURES FAVORED ACROSS PARTS OF THE NORTHERN PLAINS
    AND GREAT LAKES IN THE PREVIOUS OUTLOOK FOR JFM AND FMA 2015 WAS REPLACED WITH
    EC IN THIS SET OF OUTLOOKS. BELOW NORMAL TEMPERATURES ARE FAVORED DURING NDJ
    2014-15 FROM NEW MEXICO EASTWARD TO THE WESTERN GULF COAST STATES INCLUDING
    AREAS OF THE SOUTHERN PLAINS. THE HIGHLIGHTED REGION OF BELOW NORMAL
    TEMPERATURES IS EXPANDED EASTWARD AND SOMEWHAT NORTHWARD TO INCLUDE THE
    LOWER-TO-CENTRAL MISSISSIPPI VALLEY, TENNESSEE VALLEY, SOUTHEAST AND LOWER
    MID-ATLANTIC THROUGH JFM 2015 WITH A SLIGHT DECREASE IN COVERAGE IN FMA 2015.

    THE EVOLUTION IN THE TEMPERATURE OUTLOOKS FOR THE FIRST FOUR LEADS DEPICTED IS
    FURTHER SUPPORTED BY 500-HPA HEIGHT AND TEMPERATURE FORECASTS FROM THE
    CONSTRUCTED ANALOG DERIVED FROM GLOBAL SSTS ALONG WITH A DECREASE OR REMOVAL OF
    ABOVE NORMAL MEAN TEMPERATURE PROBABILITIES FROM MANY OF THE NMME AND IMME
    PARTICIPANT MODELS.

    ABOVE NORMAL TEMPERATURES ARE FAVORED FOR ALASKA AND THIS IS SUPPORTED BY
    DYNAMICAL MODEL GUIDANCE AND ANOMALOUSLY WARM WATERS IN PROXIMITY TO THE STATE.
    ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FOR NEW ENGLAND THROUGHOUT THE
    WINTER BASED ON THE CONSTRUCTED ANALOG TEMPERATURE FORECAST, NEARBY OCEAN
    TEMPERATURES AND MODESTLY HIGH PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FROM
    THE NMME AND IMME GUIDANCE.

    THE OUTLOOK MAPS FROM AMJ 2015 AND BEYOND REMAINED LARGELY UNCHANGED FROM THE
    PREVIOUS OUTLOOKS. ENHANCED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE
    FORECAST FOR NORTHERN ALASKA THROUGH NDJ 2015-16. THE ANOMALOUS DELAY IN ARCTIC
    OCEAN AND BERING SEA SEA-ICE COVER FOR OCTOBER AND NOVEMBER IN THE LAST DECADE
    RELATIVE TO THE 1981-2010 CLIMATOLOGY PERIOD RESULTS IN GREATLY ENHANCED
    PROBABILITIES OF ABOVE-NORMAL TEMPERATURES FOR PARTS OF NORTHERN AND
    NORTHWESTERN ALASKA FROM ASO – OND 2015.

    PRECIPITATION

    THE PRECIPITATION OUTLOOK MAPS THROUGH FMA 2015 WERE PRIMARILY BASED ON
    POTENTIAL EL NINO CONDITIONS, DYNAMICAL MODEL FORECAST GUIDANCE FROM THE NMME
    AND IMME AND THEIR PARTICIPANT MODELS. PRECIPITATION FORECASTS FROM THE GLOBAL
    SST BASED CONSTRUCTED ANALOG TOOL WAS ALSO CONSIDERED. DYNAMICAL MODEL GUIDANCE
    TENDED TO INDICATE INCREASED WETNESS IN MANY AREAS OF THE CONUS AS COMPARED TO
    GUIDANCE LAST MONTH.

    ABOVE AVERAGE PRECIPITATION IS FAVORED FROM SOUTHERN CALIFORNIA ACROSS THE
    SOUTHWEST, SOUTHERN PLAINS AND SOUTHEAST CONUS FROM NDJ 2014-15 THROUGH FMA
    2015. THIS IS CONSISTENT WITH EL NINO CONDITIONS AND GENERALLY SUPPORTED BY
    MODEL GUIDANCE. EL NINO COMPOSITES ALSO WEAKLY SUPPORT AN INCREASE IN THE ODDS
    FOR ABOVE AVERAGE PRECIPITATION NORTHWARD ALONG THE EASTERN SEABOARD TO
    SOUTHERN NEW ENGLAND AND THIS ALONG WITH CONSIDERABLE SIGNALS IN THE NMME AND
    IMME MODEL GUIDANCE SUPPORT ADDING THIS REGION TO BOTH THE NDJ AND DJF 2014-15
    PRECIPITATION OUTLOOKS. BOTH EL NINO CONSIDERATIONS AND MODEL GUIDANCE ALSO
    SUPPORT AN EXPANSION OF THE FAVORED ABOVE AVERAGE PRECIPITATION FOR THE CENTRAL
    ROCKIES AND CENTRAL HIGH PLAINS DURING JFM AND FMA 2015.

    ENHANCED PROBABILITIES FOR BELOW-MEDIAN PRECIPITATION ARE INDICATED FOR THE
    PACIFIC NORTHWEST THROUGH MAM 2015, AND FROM THE CENTRAL MISSISSIPPI VALLEY
    INTO THE GREAT LAKES REGION FROM NDJ 2014-15 THROUGH MAM 2015. A LESS ROBUST
    SIGNAL THIS MONTH IN DYNAMICAL MODEL GUIDANCE IN THE PACIFIC NORTHWEST WAS THE
    BASIS FOR THE SLIGHT REDUCTION IN COVERAGE AND PROBABILITIES OF BELOW MEDIAN
    PRECIPITATION IN NDJ AND DJF 2014-15 IN THIS AREA WHEN COMPARED TO PREVIOUSLY
    ISSUED FORECASTS FOR THESE SEASONS. PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION
    ARE ENHANCED FOR PARTS OF SOUTHERN ALASKA THROUGH FMA 2015.

    PROBABILITIES OF BELOW-MEDIAN PRECIPITATION ARE ENHANCED FOR PARTS OF THE
    SOUTHWEST DURING AMJ AND MJJ 2015 AND FOR THE PACIFIC NORTHWEST IN THE JAS AND
    ASO 2015 SEASONS DUE TO DECADAL TRENDS.

    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/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 NOV 20 2014

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