What is a heat dome?

The heat has been relentless across the southern half of the country. Heat alerts are in effect from California to Florida. Here in North Texas, the temperature on Tuesday, July 18 reached 108 degrees. The highest so far this year.

Phoenix is making headlines for all the records being set in the city. As of Tuesday, July 18th residents there are experiencing their 19th day of 110 degree or great heat.

This is all being blamed on a 'heat dome'- but what exactly is a heat dome?

A heat dome is when a high-pressure circulation in the atmosphere acts like a dome or cap, trapping heat at the surface and favoring the formation of a heat wave.

Here in North Texas, the heat dome will retreat to the west this weekend allowing for some slight heat relief. Over the weekend highs will be in the 90s. The heat dome then quickly returns next week with triple digits back in the forecast.