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HOME > Climate & Weather Linkage > El Niño / Southern Oscillation > 850 hPa Zonal Wind Index
850 hPa Zonal wind indices : Observation and Forecasts
The zonal wind indices are obtained by averaging the daily (00Z) zonal wind anomalies over the indicated area. Note that positive values of the 850 hPa zonal wind indices imply easterly anomalies.
The zonal wind indices and their forecasts using GFS and Enesmble mean forecast data are shown for the previous 120 days as indicated and they are normalized by standard deviation using 1979-1995 base period. A 3-day running mean is applied for the forecast indices.
5°N-5°S, 135°E-180° Observation GFS Ensemble Mean
5°N-5°S, 175°E-140°W Observation GFS Ensemble Mean
5°N-5°S, 135°W-120°W Observation GFS Ensemble Mean

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Page last modified: April 9, 2008
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