Skip Navigation Links 
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

HOME > Expert Assessments > Climate Diagnostics Bulletin > Forecast Forum
Forecast Forum - September 2002

The canonical correlation analysis (CCA) forecast of SST in the central Pacific (Barnett et al. 1988, Science, 241, 192-196; Barnston and Ropelewski 1992, J. Climate, 5, 1316-1345), is shown in Figs. F1 and F2. This forecast is produced routinely by the Prediction Branch of the Climate Prediction Center. The predictions from the National Centers for Environmental Prediction (NCEP) coupled ocean/atmosphere model (Ji et al. 1998, Mon. Wea. Rev, 126, 1022-1034) are presented in Figs. F3 and F4a, F4b.  Predictions from the Markov model (Xue, Y., A. Leetmaa, and M. Ji, 2000: ENSO prediction with Markov model: The impact of sea level. J. Climate, 13, 849-871) are shown in Figs. F5 and F6.   Predictions from the latest version of the LDEO model (Chen, D., M. A. Cane, S. E. Zebiak, Rafael Canizares and A. Kaplan, 2000, Geophys. Res. Let., 27, 2585-2587) are shown in Figs. F7 and F8. Predictions using linear inverse modeling (Penland and Magorian 1993, J. Climate, 6, 1067-1076) are shown in Figs. F9 and F10. Predictions from the Scripps / Max Planck Institute (MPI) hybrid coupled model (Barnett et al. 1993, J. Climate, 6, 1545-1566) are shown in Fig. F11.   Predictions from the ENSO-CLIPER statistical model (Knaff, J. A. and C. W. Landsea 1997, Wea. Forecasting, 12, 633-652) are shown in Fig. F12.

The CPC and the contributors to the Forecast Forum caution potential users of this predictive information that they can expect only modest skill..


Based on the observed oceanic and atmospheric conditions and the SST predictions, moderate warm episode (El Niņo) conditions are expected to continue into early 2003.


Moderate warm episode (El Niņo) conditions dominated the tropical Pacific during September 2002. SST anomalies (departures from average) remained greater than +1°C throughout the central equatorial Pacific between 180°W and 125°W during the month (Fig. T18), and positive subsurface temperature anomalies (Fig. T17) and a deeper-than-average oceanic thermocline (Figs. T15 and T16) prevailed throughout most of the equatorial Pacific.

Atmospheric indicators of El Niņo include consistently negative values of the Southern Oscillation Index (SOI) since March 2002 (Table T1), and weaker-than-average low-level easterly winds since May 2002 throughout the equatorial Pacific (Fig. T7). In addition, above-average precipitation has been observed over the tropical Pacific, especially in the vicinity of the date line (180°W), while drier-than-average conditions prevailed over many sections of Indonesia, India, Mexico and Central America (Fig. E3). These oceanic and atmospheric conditions indicate the presence of El Niņo.

Most coupled model and statistical model forecasts indicate that El Niņo conditions will continue into early 2003 (Figs. F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12) . Based on the recent evolution of conditions in the tropical Pacific, we expect SST anomalies to increase further in the eastern equatorial Pacific (Niņo 3 and Niņo 1+2 regions), with the establishment of basin-wide mature El Niņo conditions during December 2002-February 2003. Furthermore, based on the latest predictions and an assessment of current oceanic and atmospheric conditions, we expect that this event will be substantially weaker than the 1997-98 El Niņo. Thus, the global impacts should generally be weaker than those observed during 1997-98. However, strong impacts are still possible in a few locations.

Expected global impacts include: 1) drier-than-average conditions over Indonesia and eastern Australia continuing during the next several months, 2) wetter-than-average conditions over southeastern South America (Uruguay, northeastern Argentina, and southern Brazil) during the next three months, 3) drier-than-average conditions over southeastern Africa during December 2002-February 2003, and 4) wetter-than-average conditions over coastal sections of Ecuador and northern Peru during December 2002-April 2003. Over the United States and Canada we expect: 1) drier-than-average conditions in the Pacific Northwest and mid-Atlantic states during fall 2002 and in the Ohio Valley states and northern Rockies during winter 2002-2003, 2) wetter-than-average conditions along much of the southern tier of the U.S. during winter 2002-2003, and 3) warmer-than-average conditions in the northern tier states, southern and southeastern Alaska, and western and central Canada during late fall 2002 and winter 2002-2003.

Weekly updates of SST, 850-hPa wind, OLR, and the equatorial subsurface temperature structure are available on the Climate Prediction Center homepage at: (Weekly Update).

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: October 15, 2002
Disclaimer Privacy Notice