Hurricane Sally (2020) shifts the ocean thermal structure across the
inner core during rapid intensification over the shelf
Abstract
Prediction of rapid intensification in tropical cyclones prior to
landfall is a major societal issue. While air-sea interactions are
clearly linked to storm intensity, the connections between the
underlying thermal conditions over continental shelves and rapid
intensification are limited. Here, an exceptional set of in-situ and
satellite data are used to identify spatial heterogeneity in sea surface
temperatures across the inner core of Hurricane Sally (2020), a storm
that rapidly intensified over the shelf. A leftward shift in the region
of maximum cooling was observed as the hurricane transited from the open
gulf to the shelf. This shift was generated, in part, by the surface
heat flux in conjunction the along and across-shelf transport of heat
from storm-generated coastal circulation. The spatial differences in the
sea surface temperatures were large enough to potentially influence
rapid intensification processes suggesting that coastal thermal features
need to be accounted for to improve storm forecasting as well as to
better understand how climate change will modify interactions between
tropical cyclones and the coastal ocean.