Catonsville set a new Maryland record for annual precipitation in 2018: nearly 85 inches, meteorologists confirm.
Until now, Maryland did not have an official precipitation record within National Centers for Environmental Information documentation of state-by-state climate extremes. Totals as high as 78 inches had been reported, but never thoroughly vetted, in northern Carroll County, Towson and at Catoctin Mountain Park.
But last year, there were 10 reports around the state exceeding those marks.
At the top of the list was a rain gauge in a Catonsville backyard, one of a cluster with extreme readings around the Ellicott City area. Those areas were hit with severe flooding May 27, the largest of many deluges to hit the region in 2018.
Operated by a National Oceanic and Atmospheric Administration contractor with bachelor’s and master’s degrees in meteorology, the gauge measured 84.56 inches across the calendar year. That included 9.47 inches of rainfall during the May 27 flooding, a measurement meteorologists said stood out even among many extraordinary precipitation reports that day.
A committee dedicated to reviewing state climate extremes investigated and voted unanimously to adopt the reading as Maryland’s first extreme precipitation record. The NCEI made the record official this month.
Precipitation records were widespread across the region in 2018, with extreme rainfall arriving in May and developing persistently through the rest of the year. It was Baltimore’s wettest year ever, as measured at the region’s point of record, Baltimore-Washington International Thurgood Marshall Airport. Nearly 72 inches of precipitation fell at BWI in 2018.
But the Catonsville record, and other widespread totals exceeding previous extremes, show the full extent of the year’s precipitation. Normal annual precipitation in Baltimore is about 43 inches.
According to the record report, other extreme rainfall totals in 2018 included:
» 84.35 inches near Thurmont;
» 80.86 inches in Towson;
» 80.78 near Mechanicsville;
» 80.57 in Eldersburg;
» 79.41 near Kingsville;
» 79.35 near Millers;
» 79 inches in Ellicott City;
» 78.72 inches, also near Kingsville; and,
» 78.38 in Linthicum.