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Abstract Tropical cyclones (TCs) generate extreme precipitation with severe impacts across large coastal and inland areas, calling for accurate frequency estimation methods. Statistical approaches that take into account the physical mechanisms responsible for these extremes can help reduce the estimation uncertainty. Here we formulate a mixed‐population Metastatistical Extreme Value Distribution explicitly incorporating non‐TC and TC‐induced rainfall and evaluate its implications on long series of daily rainfall for six major U.S. urban areas impacted by these storms. We find statistically significant differences between the distributions of TC‐ and non‐TC‐related precipitation; moreover, including mixtures of distributions improves the estimation of the probability of extreme precipitation where TCs occur more frequently. These improvements are greater when rainfall aggregated over durations longer than one day are considered.
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This content will become publicly available on February 17, 2026
Hurricane Hilary (2023) and Rare Tropical Cyclones in the Southwest United States: Impacts on Temperature and Precipitation
Abstract Hurricane Hilary brought extensive, record‐breaking precipitation to the Southwest United States in August 2023. Although tropical cyclones (TCs) are uncommon in this region, they can cause substantial damage, primarily through flooding. However, heat extremes associated with these TCs are understudied and could have significant impacts in populated coastal areas. This study examines the conditions that promoted the occurrence of 42 north‐reaching, northeastern Pacific TCs and quantifies how local temperatures responded to these storms. Using composite analysis, we find that there is significant warming along the coastal region of Southern California preceding a TC, particularly for storms that remain offshore. Three main mechanisms contribute to this warming pattern—adiabatic compression associated with downslope winds, warm air advection by the TC itself, and suppression of coastal upwelling. These compound heatwave‐TC events are an overlooked impact of TCs that will likely become more important as the climate warms.
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- Award ID(s):
- 2105654
- PAR ID:
- 10573198
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Atmospheres
- Volume:
- 130
- Issue:
- 4
- ISSN:
- 2169-897X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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