Some towns in Connecticut saw more than 12 inches of rain earlier this week after storms on Sunday and Monday caused fatal flooding in the southwestern part of the state.
According to data from the Community Collaborative Rain, Hail and Snow Network — also known as CoCoRaHS — Newtown saw the most precipitation with 12.17 inches. Newtown is adjacent to Oxford, where two residents died in floodwaters. There are no CoCoRaHS rain gauges in the town of Oxford itself.
In Southbury, where a CoCoRaHS rain gauge measured almost 6.7 inches of precipitation as of Monday morning, residents were left stranded as the heavy rains damaged homes, washed out roads and knocked out power.
New Canaan and Woodbury also saw lots of rain, with more than 7 inches measured in each town.
CoCoRaHS gets its precipitation measures from more than 100 gauges located around the state.
Gauges manned by other entities recorded even higher rainfall measures — including some that broke precipitation records in Connecticut, pending verification from the National Weather Service.
A Mesonet station in Oxford, for instance, recorded 14.83 inches of rain as of early Monday morning. A public gauge and a Citizen Weather Observer Program gauge both recorded around 13.5 inches in Oxford.
The National Weather Service said its verification process for the rainfall record will take two to four weeks, according to NBC Connecticut.
Connecticut’s previous rainfall record for a 24-hour period was 12.77 inches, recorded in Burlington in 1955 after Tropical Storm Diane hit the region.
Fairfield and New Haven counties faced the bulk of the rain — and resulting high water levels.
River gauges throughout the two counties recorded drastic increases in water levels on Sunday night and Monday morning. One of the highest was on the Still River, where a gauge in Brookfield measured a water level of over 17 feet shortly before 4 a.m. Monday. The record high for water levels in the Still River at that gauge is 19 feet, according to the U.S. Geological Survey.
Towns in southern Litchfield and Hartford counties also saw high precipitation levels.
While likely record-breaking, this week’s rains were part of a year that’s been wetter overall. Across all eight of Connecticut’s counties, precipitation levels in most months this year have been higher than typical levels.
The National Weather Service measures normal precipitation levels based on averaged data from 1990 through 2020. In most counties across Connecticut, six months this year — including August so far — have been wetter than average. In Tolland County, that number is even higher, with seven months of 2024 seeing higher-than-typical precipitation levels.
The upward trend is a consequence of climate change, according to scientists, as both droughts and extreme rainfall become more common globally. While specific precipitation measurements vary locally, data from Hartford shows that rainfall intensity in the state has generally increased 11% since 1970, according to an analysis by nonprofit news organization Climate Central.
A warmer atmosphere can hold more water vapor, which means more rainfall in places like Connecticut, Peter Girard, Climate Central’s vice president of communications, told the CT Mirror.
