Between 5 and 11 inches of rain fell overnight on Nov. 4 and 5 across a stretch of north Georgia only 20 miles long by 10 miles wide, a 20-by-10-mile patch covering parts of Fannin and Gilmer counties. The Weather Channel’s Jonathan Erdman traced the deluge to storm clusters that stalled for hours over the mountains. Their combined output set off the flooding on the Toccoa and Ocoee rivers that closed McCaysville.
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Fannin and Gilmer counties, where the 11-inch totals landed
The wettest ground lay along the line between the two counties. A write-up by a river-conservation group in the Etowah basin, citing the National Weather Service, put the heaviest rain just south of McCaysville near the Fannin-Gilmer line, with roughly 8 to 11 inches in 24 hours. Erdman’s map of the Nov. 4-5 accumulation topped out at 11 inches, while the 5-inch end of his range covers the edges of the same 20-by-10-mile area.
Blue Ridge and Cherry Log, about 75 miles north of Atlanta, were among the first places where water reached homes, just before midnight on Wednesday. By then the Weather Service’s Peachtree City office had been warning all day. Its Nov. 4 forecast discussion called for rounds of widespread rain over north Georgia and added that localized flash flooding could not be ruled out, especially where drainage is poor.
Surface observations posted by the office around midday on Nov. 4 already showed what was coming: rain, mist and lightning at Blairsville and Ellijay, with thunder near Ellijay, visibility down to half a mile and gusts to 17 mph. Those reports describe conditions at one moment, not totals, but they place active convection over the north Georgia foothills roughly twelve hours before the worst rain reached Fannin County.
Stalled cells and rain rates of 2 to 3 inches per hour
Showers and storms moving across the southern Appalachians ahead of a cold front on the evening of Nov. 4 broke into clusters, and several of them barely moved. The Weather Channel reported that the stalled cells produced rates of 2 to 3 inches per hour for several hours. Three inches in one hour on a steep hillside runs off almost as fast as it lands, and rain rates of that size, more than the nightly sum, are what push small creeks over their banks.
Mountain terrain did the rest, sending runoff quickly into the Toccoa and Ocoee rivers. Those two names belong to one river, which changes name at the state line. The overnight timing compounded the problem, Erdman wrote, because many residents were likely asleep as the water rose, and the Weather Service answered with a flash flood emergency, an alert it issues only for severe, life-threatening flooding capable of catastrophic damage. McCaysville’s own emergency is covered separately; the rainfall is the part of the story that decided everything downstream.
Radar, gauges and why the published totals disagree
Totals differed depending on who measured and where. At 6:39 a.m., relayed Weather Service text gave 3 to 5 inches in north-central Fannin County with no more expected, and a pre-dawn warning cited 3 to 6 inches from radar and gauges. FOX Weather’s own reporting cited 5 to 8 inches across much of the region in about 12 hours, and ABC News reported six to nine inches overnight.
None of those conflict once the geography is clear. The 11-inch figure belongs to the small core, while the lower numbers describe wider swaths and earlier moments in the storm. Radar estimates, rain gauges and the storm reports that forecasters assemble later all sample different pieces of a patch this small, and a gauge sitting outside the core can miss the heaviest rain. No single reviewed maximum from the Weather Service was available as of Nov. 5.
Erdman placed the storm in a run of recent trouble, calling it the latest in a string of flash flood events over the past couple of weeks across the South, including Florida and the Desert Southwest. FOX Weather tied the Georgia and Tennessee storms to the southern end of a large cross-country system that was moving toward the East Coast. Relayed Weather Service text said the cold front would clear the region on Thursday, with rain chances at 10% or less into the middle of the following week and possible frost or freeze in far north Georgia on Sunday and Monday.
Blue Ridge Dam and the water that never reached it
Blue Ridge Dam, run by the Tennessee Valley Authority, had been storing runoff since Nov. 3, according to the conservation group’s account, yet much of this rain landed on creeks downstream of it. As the group framed it, a reservoir cannot absorb what never flows into it.
The flood that followed crested at about 18 feet on the Copperhill gauge, topping a mark from February 1990, and FOX 5 Atlanta counted 57 overnight rescues. Final reviewed rainfall figures from the Weather Service offices in Peachtree City and Morristown, and the storm-report totals that go with them, are what will settle how much fell on the core of the patch, and whether the 11-inch ceiling on Erdman’s map holds up once gauges and radar are reconciled.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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