Editor's Note — Following is an update to a previous story
The National Weather Service at Morristown was already warning of the potential for flooding rains next week. But in Thursday evening's updated forecast, the NWS revised its projected rain totals for next week: it doubled them.
Earlier Thursday, the NWS had forecasted two to three inches of rain for Scott County and the northern Cumberland Plateau next week. In its revised forecast later in the day, the NWS was projecting four to six inches of rain for the northern plateau region, with even greater totals further south.
The revised forecast came as some weather models showed more than a foot of rain falling across the northern plateau — and several inches more than that further south.
Please continue to monitor the forecast with the potential for more heavy rain next week. It's still too far out for specifics, but flooding could be a concern with the heavy rain and already very wet soil. #mrxwx pic.twitter.com/epOEvK3txt— NWS Morristown (@NWSMorristown) February 15, 2019
The issue is a frontal boundary that is expected to stall in the Mid-South region next week, with multiple areas of low pressure moving along the stalled boundary and dumping copious amounts of rain. In a forecast discussion posted Thursday afternoon, NWS meteorologists said flooding is not expected with the first round of rainfall, on Tuesday, but a second round of rainfall later in the week could be more of an issue.
Before next week's anticipated rains arrive, there will be two separate systems produce rain. The first will be on Friday and into early Saturday. The second will be on Sunday. The NWS said neither is expected to produce flooding, with rainfall totals of an inch or less with each system. But, meteorologists said, the rains would keep the ground saturated ahead of next week's heavier rains.
For perspective, minor flooding in Scott County on February 7 was caused by three inches of rain in 24 hours. U.S. Hwy. 27 south of Robbins was closed by flood waters from Black Wolf Creek, while Norma Road was partially closed by a mudslide and the Big South Fork River rose more than 25 feet in just over 12 hours, cresting with a streamflow of nearly 70,000 cubic feet per second.
Already, Oneida has received more rainfall in February than it typically receives during the month — with exactly half the month still to go. In a typical year, 4.01 inches of rainfall accumulates in Oneida. So far in February 2019, 5.31 inches of rain have been recorded.
Since the year began, Oneida has received 11.82 inches of rain, nearly double the average of 6.54 inches. It's not the wettest start ever to a year; 2011 saw more than 14 inches of rain fall through Valentine's Day. But it's close.
Since September 1, 42.83 inches of rainfall have been recorded in Oneida. Even if it did not rain a drop for the next 48 days, until April 3, it would be the wettest seven-month period of September-March on record in Oneida.
The original story follows:
Another week, more rain.
The National Weather Service at Morristown says more flash flooding is possible in East Tennessee early next week — marking the third consecutive week of flooding threats throughout the region.
In an email briefing Thursday morning, the NWS said that heavy rains could cause flash flooding throughout East Tennessee early next week, while long duration rains could cause flooding of rivers and larger creeks, as well.
The NWS said that the highest chances for problematic rainfall will come Tuesday and Wednesday, though rain could start as early as Monday night.
The heaviest rains are expected south of the northern Cumberland Plateau. The NWS is forecasting four to six inches of rain in the greater Chattanooga area, with three to four inches of rain for the southern plateau and southern valley. For the northern plateau and northern valley locations, the NWS is currently forecasting two to three inches of rain.
"Before this event, we will have light to moderate rains Friday and again Sunday that will keep the soil moist and most waterways running above normal, thereby enhancing the potential for problems from the following heavy rains," NWS meteorologists said in an email to county emergency management planners on Thursday.
Flooding has been an issue all month. Heavy rains on February 6-7 caused widespread minor flooding issues in Scott County. More recently, heavy rains on February 12 caused minor flooding, but no real issues.