With scorching temperatures in the mid to upper 90s over parts of the Southeast, thunderstorms will serve as the only source of relief. However, some areas of the Southeast will receive more than they bargained for as some of the storms Monday evening will become severe, capable of supporting large hail and damaging winds.
A cold front will be dragged southeastward across the Appalachians by a small shortwave trough throughout the day Monday. Partnered with a very moist and highly environment, areas in the vicinity of the shortwave will encounter scattered thunderstorm development.
Along and west of the Appalachians and in southern Virginia and northern North Carolina , an existing mesoscale convective system associated with the surface low will bring widespread thunderstorms late in the morning through the afternoon. The outflow from these storms may produce very high wind gusts ahead of the main line. In addition to damaging winds, there is a slight chance for the development of hail, although the risk is greater further south and east.
East of the Appalachians and south of the initial line of storms in the Carolinas, isolated storms will become more widespread throughout the afternoon, eventually forming clusters as the front sags closer. Weak steering winds over South Carolina may result in a high risk of flash flooding as storms will be slow moving. Temperature in the upper 90s will provide enough fuel for the growth of large hail and development of microbursts. Microbursts are intense downdrafts of wind produced by a thunderstorm. Torrential rainfall and evaporation may result in them being produced in some of the storms, resulting in localized wind damage. Outflow ahead of the storms producing straight-line winds will be another source of wind damage.
Scattered storms are also expected over Georgia, Tennessee and eastern North Carolina but the ingredients for severe weather are only capable of producing isolated severe storms. Distance from the front and cloud debris will limit how widespread and how intense these storms become.
With the cold front stalling overnight, thunderstorms will persist into Tuesday, being most widespread over North Carolina and southern Virginia, closer to the stalled frontal boundary. Relief from the heat will be less widespread further south and east. With the retreat of the frontal boundary Wednesday, extreme heat will return by Thursday.