A flood advisory for urban areas and small streams has been issued for Sullivan County, including Kingsport, by the NWS until 8:15 p.m. Wednesday.
Forecasters said Doppler radar indicated that between one and two inches of rain had fallen in and around Kingsport.
The rainfall and heavy runoff will likely result in nuisance flooding of urban areas and streets, as well as small creeks and streams. Highways, streets and underpasses will also be impacted by ponding.
An areal flood advisory remains in effect for both Northeast Tennessee and Southwest Virginia until 6:30 p.m.
Update: 4:35 p.m.
A severe thunderstorm warning issued by the NWS for Northeast Tennessee and Southwest Virginia has been extended until 5:15 p.m.
A flood advisory has already been issued for much of Northeast Tennessee -- including Sullivan County -- until 6:30 p.m. Eastern Scott County is also included in the flood area.
The warning area includes Sullivan County, Washington County, extreme eastern Hawkins County and eastern Greene County in Tennessee. Scott County, Va. is also including in the warning.
At 4:28 p.m., NWS Doppler Radar indicated a severe thunderstorm capable of producing quarter-sized hail and damaging winds in excess of 60 mph.
Frequent cloud-to-ground lightning is also expected.
The storm, which was moving north at 25 mph, was located 6 miles southwest of Colonial Heights at approximately 4:30 p.m. and was expected to hit that area by 3:40 p.m.
The storm is expected to hit Kingsport by 4:45 p.m. before moving into Weber City and Gate City at 5 p.m.
As of 3:30 p.m., up to 1.5 inches of rain had fallen across parts of Northeast Tennessee and Southwest Virginia over the course of an hour.
Additional rainfall in the amount of an inch, or more, was expected to fall in the warning area over the course of the evening.
Excessive runoff from the heavy rainfall is expected to cause elevated water levels in small streams and creeks, as well as water ponding in urban areas. Streets, underpasses and other poorly draining areas will likely be impacted.
Update: 3:44 p.m.
The NWS has issued a flood advisory for Sullivan County, effective through 6:30 p.m.
An urban and small stream flood advisory has been issued for Carter County, Greene County and Johnson County.
The National Weather Service has issued a severe thunderstorm warning for Sullivan County, Tenn., and Washington County, Va.According to the NWS Forecasting Station in Morristown, Tenn., quarter-sized hail and winds in excess of 60 mph are possible, along with continuous cloud to ground lightning. As of 3:10 p.m. the warning was set to expire at 3:45 p.m. For the latest weather alerts visit the NWS.
Times-News staff writers Rain Smith and Wes Bunch contributed to this report.