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In June 2020, a major dust outbreak occurred in the Sahara that impacted the tropical Atlantic Ocean. In this study, the dust load and radiative forcing of the dust plumes on both the atmosphere and ocean surface is investigated by means of observations and modelling. We estimated dust loadings in excess of 8 Tg over the eastern tropical Atlantic, comparable to those observed over the desert during major Saharan dust storms. The dust induced an up to 1.1 K net warming of the ocean surface and a 1.8K warming of the air temperature (i.e., two to three times the respective climatological standard deviations), with a +14 W m−2 (∼28% of the mean value) increase in the surface net radiation flux at night. As the dust plumes extended all the way to the Caribbean, it is possible that this historical dust event helped fuel the record-breaking 2020 Atlantic hurricane season. The Saharan dust storm in June 2020 over the Atlantic Ocean heading to the Caribbean. Image Credit: NOAA. Dust is an important component of the Earth's atmosphere, with a wide range of impacts ranging from human health to effects on the ocean and climate. In fact, airborne dust aerosols modify the energy budget of the Earth's surface by interacting with the solar radiation in different ways where they absorb in the ultraviolet and longwave and reflect in the shortwave. In June 2020, massive amounts of dust were lifted from the Sahara, the major dust source region in the world, and transported all the way into the Americas across the tropical Atlantic Ocean. During this event, large dust loads, in excess of 8 Tg, covered the tropical Atlantic Ocean and induced a radiative forcing at the surface. The energy budget of the atmosphere and the ocean surface was impacted during this event resulting in a sustained warming during night and a cooling during day. The resulting effect of dust during this event was an increase in the air temperature and the sea surface temperature associated with an increase in the longwave radiation especially during night due to the re-emission of radiation towards the surface by the dust clouds. This warming may have contributed to the very active tropical storms' season in summer 2020. [Display omitted] • June 2020 Saharan dust storm associated with highest-on-record aerosol optical depths. • The estimated dust loads exceeded 8 Tg over the eastern tropical Atlantic. • The dust event caused a net warming of the ocean surface by up to 1.1 K. • Dust may have contributed to the extremely active 2020 Atlantic hurricane season. [ABSTRACT FROM AUTHOR]