The daily NAO index correpsponds to the NAO patterns, which vary from one month to the next. Click here for the methodology used to calculate the daily NAO index.

The daily NAO index for the past 120 days. Each daily value has been standardized by the standard deviation of the monthly NAO index from 1950 to 2000 interpolated to the day in question.

• Monthly mean NAO index since January 1950

• Animations (circulations)

• GFS NAO outlooks
• Ensemble mean NAO outlooks

• North Atlantic Oscillation (NAO)

Barnston, A. G., and R. E. Livezey, 1987: Classification, seasonality and persistence of low-frequency atmospheric circulation patterns. Mon. Wea. Rev., 115, 1083-1126.

Chen, W. Y., and H. van den Dool, 2003: Sensitivity of Teleconnection Patterns to the Sign of Their Primary Action Center, Mon. Wea. Rev., 131, 2885-2899.

van den Dool, H. M., S. Saha, and Å. Johansson, 2000: Empirical Orthogonal Teleconnections. J. Climate, 13, 1421-1435.