Therefore, for the prediction of "two ridges and one trough" system, we should not only pay attention to the anomaly center, but also pay attention to the strengthening westward movement of the low-frequency positive anomaly center.
Therefore, for the forecast of "two ridges and one trough" system, we should not only pay attention to the abnormal center, but also pay attention to the westward shift of the low-frequency positive abnormal center.