. . . . . . . . PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS CLIMATE PREDICTION CENTER NCEP NATIONAL WEATHER SERVICE WASHINGTON DC 3 PM EDT THURSDAY NOV 21 2002 MODERATE WARM EVENT ENSO (EL NINO) CONDITIONS HAVE CONTINUED OVER THE EQUATORIAL PACIFIC DURING THE PAST FEW MONTHS - WITH SST ANOMALIES GREATER THAN PLUS TWO DEGREES C LOCATED ACROSS MUCH OF THE EQUATORIAL PACIFIC BETWEEN THE DATE LINE AND 100W. RECENT SST ANOMALIES IN THE IMMEDIATE VICINITY OF HAWAII HAVE AVERAGED SLIGHTLY BELOW NORMAL AND ARE EXPECTED TO HAVE A MORE DIRECT IMPACT ON THE MONTHLY TEMPERATURE OUTLOOK FOR DECEMBER. THE PRINCIPAL STATISTICAL TOOLS CONTINUE TO SHOW A PREFERENCE FOR ABOVE NORMAL - ESPECIALLY AT HONOLULU WHICH HAS A PRONOUNCED WARM TREND - PROBABLY DUE TO URBAN INFLUENCES. HOWEVER TEMPERATURES AT HONOLULU HAVE BEEN NEAR NORMAL DURING THE PAST 30 DAYS. A BALANCE AMONG THE TOOLS WAS USED TO FORMULATE THE TEMPERATURE FORECAST. NONE OF THE TOOLS GAVE ANY INDICATIONS FOR PRECIPITATION. FCST AVE LIM FCST BLW MEDIAN ABV HILO B2 72.4 0.5 EC 5.8 8.3 12.0 KAHULUI B3 73.6 0.5 EC 1.3 2.3 2.9 HONOLULU EC 74.5 0.7 EC 1.1 1.5 2.9 LIHUE EC 73.2 0.5 EC 2.2 3.6 4.7 . . . . . . . . REFER TO THE 90 DAY DISCUSSION FOR FORECASTS OF EQUATORIAL PACIFIC SST AND DETAILS OF THE GENERAL BACKGROUND TO THE FORECAST. THE CURRENT PACIFIC WARM EPISODE (EL NINO) IS PREDICTED TO CONTINUE AT LEAST INTO SPRING 2003 - AND WOULD PROBABLY HAVE ITS GREATEST EFFECTS ON THE SUBTROPICAL AND MIDDLE LATITUDE CIRCULATION DURING THE WINTER - ALTHOUGH SOME INFLUENCES OF THE EQUATORIAL PACIFIC ON THE CIRCULATION AT MIDDLE LATITUDES ARE LIKELY AT ANY TIME FROM NOW THROUGH SPRING. DURING PAST EL NINO EPISODES TEMPERATURES DURING THE COLDER HALF OF THE YEAR HAVE TENDED TO BE BELOW NORMAL IN MOST OF HAWAII. THE URBAN-RELATED WARMING TREND AT HONOLULU WOULD COUNTERACT THE EL NINO-RELATED COOLING AND THE OCN TOOL WHICH PICKS UP DECADAL SCALE TRENDS HAS THE MOST CONSISTENT INDICATIONS FOR WARMTH AT THAT STATION. THE FORECASTS SHOWN IN THE TABLES BELOW REFLECT PRIMARILY THE INFLUENCE OF THE WARM EPISODE ENSO COMPOSITES AND ARE SHADED TOWARDS BELOW NORMAL TEMPERATURES DURING THE WINTER AND SPRING SEASONS. THERE WERE FEW SIGNIFICANT INDICATIONS FOR PRECIPITATION FROM THE STANDARD TOOLS EXCEPT A COUPLE OF WEAK HINTS FOR DRIER THAN NORMAL DURING JFM - AMJ 2003 - BUT THE USUAL EL NINO-FORCED SOUTHWARD-DISPLACED STRONG ALEUTIAN LOW IS EXPECTED TO PUSH THE SUBTOPICAL RIDGE SOUTH TO THE VICINITY OF HAWAII - WEAKENING THE TRADE WINDS AND LOWERING PRECIPITATION AMOUNTS. THIS EFFECT ALSO PEAKS DURING THE WINTER AND SPRING AND IS EXPECTED TO BE THE PRIMARY CLIMATE ANOMALY SIGNAL DURING THESE SEASONS. AFTER LATE SPRING 2003 THERE ARE NO DISCERNABLE FORECAST SIGNALS - SO EC IS FORECAST FOR ALL SUBSEQUENT LEADS. NOTE - EC (EQUAL CHANCES) HAS REPLACED CL (CLIMATOLOGICAL PROBABILITIES) AT THOSE LOCATIONS WHERE THE FORECAST IS UNCERTAIN. CLARIFICATION: EC INDICATES EQUAL CHANCES THAT THE CLIMATE WILL FALL INTO ANY ONE OF THE THREE RANGES OR CATEGORIES WHOSE BOUNDARIES ARE SPECIFIED IN THE TABLES BELOW. A FORECAST SPECIFICATION OF EC MEANS THERE IS NO PARTICULAR TILT OF THE ODDS TOWARD ABOVE - NORMAL - OR BELOW NORMAL CONDITIONS IN THE OUTLOOK. FOR EXAMPLE - A4 MEANS A 4% HIGHER THAN NORMAL CHANCE THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE ABOVE CLASS - B3 MEANS A 3% HIGHER THAN NORMAL PROBABILITY THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE BELOW CLASS - AND N2 MEANS A 2% HIGHER THAN NORMAL PROBABILITY THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE NEAR NORMAL CLASS. WHEN EC IS SPECIFIED THE PROBABILITY OF THE MOST LIKELY CATEGORY CANNOT BE PREDICTED. HILO TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2003 B2 72.0 0.4 B3 20.1 27.2 35.9 JFM 2003 B4 71.8 0.4 B5 23.9 30.9 39.4 FMA 2003 B5 72.1 0.4 B6 29.5 35.9 43.1 MAM 2003 B4 72.8 0.5 B4 28.3 34.9 42.6 AMJ 2003 B3 73.9 0.4 B3 22.0 26.8 32.2 MJJ 2003 B2 75.0 0.4 B2 19.1 23.1 27.8 JJA 2003 EC 75.9 0.4 EC 19.5 24.2 29.6 JAS 2003 EC 76.3 0.4 EC 22.2 27.1 32.7 ASO 2003 EC 76.2 0.4 EC 23.4 27.0 31.0 SON 2003 EC 75.5 0.4 EC 25.8 31.7 38.4 OND 2003 EC 74.2 0.4 EC 26.1 33.1 41.3 NDJ 2003 EC 72.8 0.4 EC 25.5 32.9 41.7 DJF 2004 EC 72.0 0.4 EC 20.1 27.2 35.9 KAHULUI TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2003 B3 72.5 0.5 B3 6.8 9.0 11.7 JFM 2003 B4 72.4 0.5 B6 6.0 8.1 10.6 FMA 2003 B4 73.2 0.5 B5 4.3 6.0 8.1 MAM 2003 B3 74.4 0.6 B4 2.9 4.2 5.8 AMJ 2003 B2 75.8 0.6 B2 1.0 1.8 3.1 MJJ 2003 EC 77.3 0.6 EC 0.7 1.1 1.5 JJA 2003 EC 78.6 0.5 EC 0.8 1.1 1.3 JAS 2003 EC 79.1 0.5 EC 0.9 1.2 1.5 ASO 2003 EC 78.9 0.5 EC 1.3 1.8 2.5 SON 2003 EC 77.8 0.5 EC 2.2 3.1 4.3 OND 2003 EC 75.9 0.5 EC 4.2 5.7 7.6 NDJ 2003 EC 73.8 0.5 EC 5.7 7.8 10.4 DJF 2004 EC 72.5 0.5 EC 6.8 9.0 11.7 HONOLULU TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2003 EC 73.5 0.4 B2 5.0 6.9 9.1 JFM 2003 B2 73.5 0.4 B4 4.1 5.8 8.0 FMA 2003 B2 74.5 0.4 B5 3.4 4.6 6.1 MAM 2003 B2 76.0 0.4 B4 2.4 3.2 4.3 AMJ 2003 EC 77.7 0.4 B2 1.2 1.8 2.6 MJJ 2003 A2 79.3 0.4 EC 1.0 1.4 2.0 JJA 2003 A3 80.7 0.4 EC 0.8 1.2 1.6 JAS 2003 A4 81.2 0.4 EC 1.1 1.5 2.0 ASO 2003 A4 81.0 0.5 EC 1.7 2.6 3.8 SON 2003 A3 79.6 0.5 EC 2.7 4.0 5.9 OND 2003 A3 77.3 0.5 EC 4.5 6.2 8.4 NDJ 2003 A2 75.0 0.5 EC 4.1 6.1 8.7 DJF 2004 A2 73.5 0.4 EC 5.0 6.9 9.1 LIHUE TEMPERATURE PRECIPITATION FCST AVE LIM FCST BLW MEDIAN ABV DJF 2003 B2 72.4 0.4 B2 8.6 11.4 14.7 JFM 2003 B4 72.4 0.4 B4 8.0 10.8 14.1 FMA 2003 B5 73.1 0.4 B5 7.5 9.6 12.0 MAM 2003 B3 74.4 0.4 B4 7.3 9.2 11.4 AMJ 2003 B2 75.9 0.4 B2 5.3 7.0 9.0 MJJ 2003 EC 77.5 0.4 EC 4.6 6.2 8.0 JJA 2003 EC 78.8 0.3 EC 4.6 5.6 6.6 JAS 2003 EC 79.3 0.3 EC 5.1 6.2 7.4 ASO 2003 EC 79.0 0.3 EC 6.3 8.0 10.0 SON 2003 EC 77.7 0.3 EC 9.1 10.9 12.9 OND 2003 EC 75.6 0.3 EC 10.7 13.3 16.2 NDJ 2003 EC 73.6 0.3 EC 9.8 12.5 15.8 DJF 2004 EC 72.4 0.4 EC 8.6 11.4 14.7 FORECASTER: M. HALPERT NOTE - THESE OUTLOOKS ARE INTENDED FOR USE PRIOR TO THE START OF THEIR VALID PERIODS. WITHIN ANY VALID PERIOD OBSERVATIONS AND SHORTER RANGE FORECASTS SHOULD BE CONSULTED. ALSO - THIS SET OF OUTLOOKS WILL BE SUPERSEDED BY THE ISSUANCE OF THE NEW SET NEXT MONTH ON THURSDAY DEC 19 2003