The northern periphery of a building heat bubble stretching from the Plains to the Deep South and Eastern Seaboard will become the focus for showers and thunderstorms into the weekend.
Many of the storms will interrupt hot, humid days and warm, muggy nights with sudden downpours and blasts of strong winds.
The area at risk for these storms, which will tend to organize into complexes and move east then southeast, will extend from the central Plains to the Great Lakes and into the mid-Atlantic.
This area generally represents the northern extent of the intense, record-setting heat dome expected to persist through the weekend.
Many times, thunderstorms like these form and move along the edges of the dome of heat, thus the phrase "ring of fire."
Today, storms expected to form over Nebraska and Iowa will head toward Milwaukee, Chicago and Detroit later in the day, with both cities expecting to challenge record high temperatures.
Thunderstorms today will tend to move along the northern boundary of the worst heat from the Plains to the Great Lakes and eventually into the mid-Atlantic at night (not pictured).
Toward and after dark, cities such as Cleveland, Buffalo and Erie will be under the gun for some strong storms as a batch of storms slides out of southern Ontario and across the eastern Great Lakes.
Thereafter, the activity will eventually advance through upstate New York and the Keystone State to the I-95 corridor from Washington, D.C., to Boston, early in the morning, making for a hairy proposition for morning commuters.
Farther west, the process will likely already begin repeating itself as the ring of fire stays active, with more batches of storms expected to form and push through the Rust Belt corridor at times into the weekend.
To meteorologists, this presents a unique challenge to making an accurate forecast. The placement, size, speed and direction of the thunderstorm complexes could throw monkey wrenches into what otherwise would be easier hot and sunny forecasts.
If the storms pass through your location in the afternoon, temperatures forecast to reach records may not come to fruition.
For most who don't particularly care about the exact temperature when it already is hot, it will just seem like a prototypical summer forecast, because it is "hazy, hot and humid with a shower or thunderstorm."
Still, any threat for thunderstorms should not be taken lightly. Please stay alert when you're cooling off in the lake or pool, and be ready to head indoors at the first sign of lightning.
As the heat bubble maintains itself into the weekend, the ring of fire will remain activated as thunderstorms continue to fire then move south and east periodically.
Ice, rain and snow are slamming the United States from Texas to Maine.
Thunderstorms in parts of the South this weekend may become strong enough to threaten lives and property.
As California heads into its third consecutive dry winter with no relief in sight, firefighters continue to battle a late-fall blaze in Big Sur.
Similar to the days prior to Thanksgiving, the worst weather will focus on the days prior to Christmas as millions of travelers take to the roads and skies in the U.S. and southern Canada.
An abrupt and abnormal cold wave gripped parts of southeastern Texas in early December, catching many off-guard, including two native Southern California bobcats recently transferred to the area.
Wintry and violent weather will avoid central Pennsylvania through the weekend.
Portland, OR (1892)
27.5" of snow (21st-24th).
Wind gusts to 91 mph across the San Joaquin Valley - hundreds of cars and trucks buried by blowing dust.
Richmond, VA (1942)
-1 degree F earliest ever below zero.