Continuous time weather regimes
Weather regimes are computed for the four seasons (DJF, MAM, JJA and SON) on a reference period between 1970 and 2010. The whole SLP field is then classified on those reference weather regimes. Simple diagnostics are shown, with the occurrence of weather regimes in the current (or last) season, and the frequency of the weather regimes since 1948.
The results are updated weekly. The files for the four seasons can be found at:
http://dods.lsce.ipsl.fr/dase/REGIMES/
The pdf files show the weather regimes for each season (DJF, MAM, JJA, SON: see figure above for DJF). The dat files are the classifications of all days. The first column is the day (in yyyymmdd format). The second column is the weather regime number (identified in the corresponding figure). The third column is the distance to the weather regime.
You can use those files for your own research. They are updated every week. Please cite:
REFERENCES
Legras, B. & Ghil, M. Persistent anomalies, blocking and variations in atmospheric predictability, J. Atmos. Sci., 1985, 42, 433-471
Vautard, R. Multiple weather regimes over the North Atlantic: Analysis of precursors and successors, Mon. Wea. Rev., 1990, 118, 2056-2081