While most residents of the region had never experienced the rapid flooding witnessed by those particularly in southern Washington County on Sunday and Monday, the rainfall was simply a small part of a bigger weather system.
Kate Guillet, meteorological intern with the National Weather Service in Morristown, said the line of storms that hit the local communities originated from the southwest to the northeast, moving slowly east and causing the heaviest amounts of rain to hover longer in certain areas.
“Basically, we had a line of storms and ... rainfall move through the area and there were patches along this line that had extremely heavy rainfall,” Guillet said. “Then a combination of that and that they were not moving very quickly allowed a lot of rainfall to fall in certain places, which caused flooding in localized areas across eastern Tennessee, with the worst case that we saw of flooding ... around Johnson City and Washington County.”
With official rainfall totals being recorded at Tri-Cities Regional Airport in Blountville, an area that didn’t see nearly the extreme conditions compared to areas like south Johnson City, overall rainfall could seem skewed to people who dealt with flooded basements and homes, as well as those people who were forced to abandon their cars when they came into contact with deep water on the roads.
“At the peak periods during the whole event we saw widespread values ... between 1 to 2 inches and then there were some local areas, mainly in Northeast Tennessee that were showing values of 3 to 4 inches during that ... 24-hour period,” Guillet said. “If you look at the data, it was only local areas that received the heavy rainfall. There were some areas in the county that received less than a quarter of an inch and then maybe 50 miles away they had almost 4 inches. So, it was just locally heavy rainfall with a majority of it occurring across Northeast Tennessee.”
For local rivers and streams that overflowed due to the rain, water levels are expected to subside and withdraw, as per usual.
“The terrain here is steep, so when it rains hard it washes off quick,” John Hammonds, fisheries biologist with the Tennessee Wildlife Resources Agency said. “Within a few days, unless it rains again, it will be back to normal. They go up quick and they go down quick.”
He said river and stream erosion can be expected for those naturally equipped with high banks that have no curvature, but said they tend to bounce back pretty quick either on their own or by a few man-made additions and adjustments.
“It (the rivers and streams) recovers pretty quick,” Hammonds said. “Having said that, though, there’s going to be isolated areas you’ll see affects of ... 10 years from now.”
According to Guillet, today’s forecast looks pretty dry, but rain is forecast to be on its way again.
“We are going to see another front move through which is going to have rainfall associated with it, but we’ll get the most of it on Friday,” she said. “Chances start to increase Thursday afternoon, highest on Friday and Saturday is looking fairly dry.”