FIGURE E5. Northern Hemisphere mean and anomalous sea level pressure. Mean values are denoted by solid contours drawn at an interval of 4 mb. Anomaly contour interval is 2 mb with values less (greater) than -2 mb (2 mb) indicated by dark (light) shading. Anomalies are calculated as departures from the 1979-1988 base period monthly means. The analysis should be treated with caution in regions of elevated terrain.

FIGURE E6. Northern Hemisphere mean and anomalous 500-mb geopotential height for. Mean heights are denoted by solid contours drawn at an interval of 8 dam. Anomaly contour interval is 3 dam with values less (greater) than -3 dam (3 dam) indicated by dark (light) shading. Anomalies are calculated as departures from the 1979-1988 base period monthly means.

FIGURE E7. Northern Hemisphere mean (top) and anomalous (bottom) 300-mb vector wind. Mean (anomaly) isotach contour interval is 10 (5) ms-1. Values greater than 30 ms-1 (top) and 10 ms-1 (bottom) are shaded. Anomalies are departures from the 1979-1988 base period monthly means.

FIGURE E8. Northern Hemisphere percentage of days during the month in which 500-mb height anomalies greater than 15 m (top) and less than -15 m (bottom) were observed. Values greater than 70% are shaded and contour interval is 20%.

FIGURE E9. Northern Hemisphere: Daily 500-mb height anomalies averaged over the 5o latitude band centered on 45oN. Left panel shows the full 500-mb height anomalies; middle panel shows the planetary-scale height anomalies (two-dimensional wavenumbers 0-6); right panel shows the sub- planetary-scale height anomalies (two-dimensional wavenumbers 7-12). Contour interval is 60 m and positive height anomalies are shaded in all panels. Specified wave groups are identical to those described by Blackmon (1976, J. Atmos. Sci., 33, 1607-1623). Anomalies are computed with respect to the 1979-1988 base period.

FIGURE E10. Northern Hemisphere 700 mb heights overlayed with standard deviation of high-pass filtered (periods < 10 days) height (top)and overlayed with normalized anomalous variance of high-pass filtered height (bottom). Contour interval for height (thick solid lines) is 60 m, for standard deviation (dashed contours in top panel) is 15 m (values > 40 m shaded) and for anomalous variance (thin contours in bottom panel) is 0.5 standard deviations. Thin solid (thin dashed) contours in bottom panel indicate above (below) normal height field variability, and values exceeding 0.5 standard deviations above (below) normal are shaded dark (light). Anomalous variance is normalized by the standard deviation of high-pass filtered heights calculated over the 1964-1993 base period.

FIGURE E11. Southern Hemisphere mean and anomalous sea level pressure. Mean values are denoted by solid contours drawn at an interval of 4 mb. Anomaly contour interval is 2 mb with values less (greater) than -2 mb (2 mb) indicated by dark (light) shading. Anomalies are calculated as departures from the 1979-1988 base period monthly means. The analysis should be treated with caution in regions of elevated terrain.

FIGURE E12. Southern Hemisphere mean and anomalous 500-mb geopotential height. Mean heights are denoted by solid contours drawn at an interval of 8 dam. Anomaly contour interval is 3 dam with values less (greater) than -3 dam (3 dam) indicated by dark (light) shading. Anomalies are calculated as departures from the 1979-1988 base period monthly means.

FIGURE E13. Southern Hemisphere mean (top) and anomalous (bottom) 300-mb vector wind. Mean (anomaly) isotach contour interval is 10 (5) ms-1. Values greater than 30 ms-1 (top) and 10 ms-1 (bottom) are shaded. Anomalies are departures from the 1979-1988 base period monthly means.

FIGURE E14. Southern Hemisphere percentage of days during the month in which 500-mb height anomalies greater than 15 m (top) and less than -15 m (bottom) were observed. Values greater than 70% are shaded and contour interval is 20%.

FIGURE E15. Southern Hemisphere: Daily 500-mb height anomalies averaged over the 5o latitude band centered on 45oN. Left panel shows the full 500-mb height anomalies; middle panel shows the planetary-scale height anomalies (two-dimensional wavenumbers 0-6); right panel shows the sub- planetary-scale height anomalies (two-dimensional wavenumbers 7-12). Contour interval is 60 m and positive height anomalies are shaded in all panels. Specified wave groups are identical to those described by Blackmon (1976, J. Atmos. Sci., 33, 1607-1623). Anomalies are computed with respect to the 1979-1988 base period.