Overnight storms in Chattanooga region close some schools, push yearly rainfall near record highs

Heavy rains stemming from Hurricane Zeta, which hit the Gulf Coast Wednesday, dumped from 2 to 4 inches of rain on the Chattanooga area, pushing the rainfall so far this year above the entire precipitation total for last year, making this one of the wettest years on record.

The rains delayed school openings in Hamilton and Bradley counties Thursday morning and closed schools all day in Whitfield County over concerns about flooding in low-lying areas and on some rural roads. The Hamilton County Emergency Management Agency reported portions of at least 10 roads were closed due to flooding Thursday morning. High winds downed trees at more than a half dozen locations around the county.

6000 Sandswitch Road, 1000 Boy Scout Road and 600 E 19th Street are all closed due to flooding. Additional road closures can be reported by calling 423-643-6311 from 8 a.m. - 5 p.m. Monday - Friday. After hours/weekends, reports can be made by calling 423-698-2525.

"Signal Mountain, East Ridge and Ooltewah areas had close to 4 inches of rain from Zeta," said Derek Eisentrout, the meteorologist in charge at the National Weather Service in Morristown, Tennessee. "Thankfully, these storms have pulled to the northeast of us now and have vacated the area, although we do expect some light rainfall [Thursday night]."

Darrell Guinn, the Tennessee Valley Authority's river operations support manager, said up to 5 inches of rain fell in the Blue Ridge mountains this week as a record number of hurricane-related storms have hit the region this year.

"Rainfall in the valley so far this year is 49% above normal, and October will be the 13th consecutive month of above-average precipitation in the region - the first time we've had such a prolonged period of above-average rainfall in the 131 years of records we have available," Guinn said. "If we get anywhere near normal rainfall for the rest of this year, 2020 will end up being the wettest year on record, beating out both of the past two years - which were previously the highest rainfall years. It's been very wet over the past three years in our region."

In response, TVA has opened the spillways at eight of its nine mainstream dams to help bring down rain-swollen upstream reservoirs, which helped hold back water during the exceptionally wet 2020. TVA estimates its network of 49 dams have saved nearly $1 billion in flood damage that would have otherwise occurred along the Tennessee River, including more than $780 million in Chattanooga.

The weather is expected to be rain-free for the next several days, but a cold front moving into the area will bring colder temperatures Friday. The high temperature in Chattanooga on Friday is expected to reach 58 degrees, Eisentrout said.

Zeta is the 27th named storm of a historically busy Atlantic hurricane season, which has included 11 hurricanes.

"For those still counting, 2005 still holds the record for the most number of named storms in a season (28)," the National Hurricane Center said in a tweet Wednesday.

Zeta is the fifth named storm to make landfall this year in Louisiana - the highest number since the state started keeping records in 1851.

In Chattanooga, heavy rains in February, combined with heavier-than-normal rain this spring and the near-record number of hurricanes this summer and fall, have raised rainfall totals this year near record highs. The highest rainfall year on record in Chattanooga was in 1994 when 73.7 inches of rain fell on Chattanooga - the most since record keeping began in 1879.

With the overnight rains, precipitation totals so far this year in Chattanooga topped last year's 63.16 inches of rain with more than two months left in the year.

Rainfall so far this year is 20.5 inches above normal in Chattanooga and is already close to the 65.93 inches of rain that fell in Chattanooga during all of 2018, which was the 13th highest year for precipitation on record.

Contact Dave Flessner at dflessner@timesfreepress.com or at 757-6340.