Marek Kučera 
May 2025 has been marked by unprecedented rainfall across much of the central and eastern United States, with numerous cities experiencing some of their wettest Mays on record. This deluge has led to widespread flooding, significant property damage, and heightened concerns about the increasing frequency of extreme weather events.
Record-Breaking Rainfall Across the Region
May 2025 has been remarkable for its extraordinary levels of precipitation throughout much of the central and eastern United States, with many locations recording rainfall far above their typical May averages. Persistent weather patterns have funneled abundant moisture from the Gulf of Mexico and Atlantic Ocean into these areas, resulting in repeated heavy rain events over the month.
For example, Montgomery, Alabama, which usually receives about 3.9 inches of rain during May, saw an extraordinary 9.4 inches in 2025—more than twice the normal amount. Rather than coming in a single storm, this rainfall occurred through multiple heavy showers and thunderstorms, saturating the ground and overwhelming stormwater systems. This surplus has caused widespread flooding, road closures, and stress on local infrastructure.
Further north in the Appalachian region, Johnstown, Pennsylvania experienced an increase from its average May rainfall of around 4.5 inches to more than 6.4 inches this year. Due to its valley setting, Johnstown is especially prone to rapid runoff and flash flooding when heavy rains persist, increasing risks of landslides and swollen waterways threatening homes and transportation routes.
On the East Coast, Providence, Rhode Island, also recorded unusually high precipitation totals, receiving nearly 7.7 inches of rain compared to its typical 4.7 inches. A combination of slow-moving frontal systems and rich Atlantic moisture helped generate repeated rain bursts, contributing to flooding and challenging urban drainage.
Across a wide swath of the central and eastern United States, May 2025’s rainfall has been historic, with many areas recording some of the wettest conditions ever observed for this month. This large-scale wet pattern has led officials to issue numerous flood warnings and urged communities to prepare for ongoing soggy conditions.
Composites from ESRL for May 2025, so far: https://psl.noaa.gov/data/composites/day/
