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In Fig8.2.7.3 the extended range forecasts show a distinct shift in regime away from NAO+ regime type at the beginning of the forecast towards BL+ by the second 7-day period.   By the third 7-day period the distribution is more uncertain with all regime types represented (see histogram in Fig8.2.7.2) although the majority lie within the central circle on the phase space diagrams (i.e. no strong preference for a particular regime).  Note however a subsidiary area of higher probability slightly in the BL+ sector suggesting possible persistence of that regime type albeit with low probability.

See also the section regarding Medium Range Regime Charts which gives further information on regimes within the Extended Range.

Read more about the use

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of "Weather regimes" at ECMWF (2020 article)