Understanding tropical cyclones’ (TCs) forward motion is important in assessing the duration of storm impact. TCs do not travel at a constant speed but rather speed up (accelerate) or slow down (decelerate) as they interact with evolving steering flow, midlatitude troughs, or subtropical ridges. By examining global TC observations from 1988 to 2024, we calculated empirical 10th and 90th percentiles of translation speed change within each of six global TC basins and classified each 6 h interval into one of three categories: strong deceleration (90th percentile). Annual proportions of each category were analyzed to examine temporal and spatial trends. We find that both rapid acceleration and strong deceleration have become increasingly prevalent globally. This implies that the pattern of storm motion is becoming more variable, even though the average change in translation speed has remained relatively unchanged. The increase in TC extreme acceleration and deceleration frequency is strongest in the western North Pacific and the South Indian Ocean, while the North Indian Ocean shows the opposite trend in frequencies. These basin-dependent trends are potentially linked to changes in the variability of large-scale steering flow. The results highlight that focusing only on TC annual mean translation speed may mask critical acceleration and deceleration extremes in understanding the TC behaviors in response to climate variations.

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