Tropospheric role in the predictability of the surface impact of the 2018 sudden stratospheric warming event

Sudden stratospheric warmings (SSWs) can have a strong impact on the troposphere. Their fingerprint is often associated with negative phase of Northern Annular Mode (NAM) and North Atlantic Oscillation (NAO), extreme weather high societal impact. However, mechanisms behind this downward are not well understood. We investigate surface through its predictability limits, by studying 2018 SSW event. search for barriers that occurred after onset before It found dynamical tropospheric events consisting two cyclogenesis were main reasons these in prediction NAM/NAO anomalies reaching surface. This work corroborates individual synoptic might constitute during events, thereby sheds light stratosphere-troposphere coupling.