Heavy Rain in Roanoke (c) County, Virginia

A personal weather station (Weather Underground: KVAVINTO1) measured a 2-hour rainfall amount of 3.02 inches. This amount is around a 50-year rainfall event per NOAA Atlas 14 point precipitation frequency estimates.

An upper level storm system crossed the region during peak heating. The passage of this system aided in the lift needed for thunderstorm development within an already very moist and unstable atmosphere. The environment spawned scattered severe thunderstorms which produced damaging winds. In addition, storms were at times slow-moving, with winds up to 700 mb averaging around 10 knots from the southwest. Surface-based CAPEs across central Virginia varied from 1,500 to over 2,000 J/Kg during late afternoon, while precipitable water values varied from 1.2 inches across the Mountain Empire to 1.6 inches across the Southside area of Virginia. The high instability and abundant atmospheric moisture combined to produce storms with high rainfall rates, at times observed to be up to 5 inches per hour.