But weather radars notoriously underestimate rainfall. Automated rain gauges in and around Catonsville, at ground zero, recorded nearly 13 to 15 inches of rain. The National Weather Service received a gauge report of 8.4 inches in Ellicott City.
To put this 2018 storm in perspective, about 5 inches of radar-indicated rain fell in Ellicott City July 30, 2016, while gauges back then captured 8.22 inches. So in terms of rainfall magnitude, Sunday’s storm is a likely rival, if not even more intense.