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Trends in subdaily to daily rainfall in Florida, 1990–2022

Saira Haider·Michelle M. Irizarry-Ortiz·Jayantha T. Obeysekera·Ana C. Maran·Tarana Solaiman·Brett D. Johnston
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Abstract

Changing rainfall patterns and intensifying rainfall extremes affect urban infrastructure and can increase flash-flood risk. Understanding how climate change has altered rainfall can support state and local agencies as they adapt and build resiliency. In this study, rainfall data from 23 weather stations in Florida were used to examine temporal and spatial trends over the period 1990–2022. Subdaily to daily rainfall events of durations 1, 2, 3, 6, 12, and 24 h were examined. A variety of statistical methods were applied to examine annual and seasonal trends, including quantile regression, extreme value analysis, run theory using the Mann–Kendall test, Sen–Theil slope, and Poisson and negative binomial tests, and threshold exceedance rates using generalized additive models. Using subdaily rainfall data posed challenges, including equipment failures, limited documentation of the quality assurance and control process, and potential measurement interferences. Results indicated that over 1990–2022, there was a decrease in hourly rainfall extremes but an increase at moderate quantiles. Overall, the number of rainfall events increased, particularly at shorter durations, but the mean total rainfall per event decreased. Additionally, the annual number of daily rainfall extremes showed more decreases than increases.

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Journal of HydrometeorologyArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 24.546468° to 31.000682° latitude; -87.634938° to -80.031362° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Saira Haider, Michelle M. Irizarry-Ortiz, Jayantha T. Obeysekera, Ana C. Maran, Tarana Solaiman, Brett D. Johnston. 2026-06-01. Trends in subdaily to daily rainfall in Florida, 1990–2022. https://doi.org/10.1175/jhm-d-25-0112.1

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