Upper ridge promotes hot weather, squashes significant rain chances this week

An upper ridge keeps the active storm track and significant rain north and west of the Tennessee Valley this week (Image: WHNT News 19)

HUNTSVILLE, Ala. – A summer-like weather pattern settles in once again this week meaning very hot temperatures and little threat of rain.

An upper ridge is forecast to remain overhead through at least the middle of the week. Upper-level highs tend to act like a heat pump as the sinking and compressing air they create becomes hotter.

Expect temperatures in the Tennessee Valley to be between seven and 12 degrees above average through at least Wednesday.

The sinking motion in the atmosphere caused by the upper-level high also tends to limit widespread, significant rainfall. The high will also block any storm systems from moving into the Southeast; the active storm track will stay positioned north and west of us through the middle of the week, keeping the risk of severe weather over the Great Plains and upper Midwest.

Air pollution is also a byproduct of expansive upper-level highs. The sinking motion in the air keeps pollutants closer to the ground, whereas they typically would be able to disperse higher into the atmosphere.

Air quality alerts have been posted for cities like Birmingham, Dallas, Memphis, Nashville, Chattanooga, Indianapolis, Charlotte, and Knoxville.

The upper high begins to shift east later this week, and this may allow for a few more afternoon or evening storms to develop. Click here to read the forecast discussion.

Potential rain amounts through 7 a.m. Monday, May 22 (Image: WPC)