A hot dome will hit the East next week
A severe heat wave will spread across the Midwest and much of the East during the week of the Fourth of July, with unbearable heat and intense humidity threatening millions of people from the Plains to the East Coast.
For many, the heat index is likely to be in the triple digits, with daytime low temperatures remaining very warm, providing little relief at night.
This will be a big change for those who have had cooler than normal Junes lately, especially in parts of the Plains and Midwest.
Heat began to rise in some parts of the country over the weekend and will spread eastward over the course of the week. At least 230 million people in the U.S.โabout two-thirds of the U.S. populationโcould be exposed to extreme heat, which can lead to health problems.
(CARDS: US 10-Day Forecast: Highs and Lows)
Midwest Attractions
Heat has already increased across the Plains and Midwest over the weekend and will continue across the Great Lakes and Ohio Valley through much of this week.
By Monday, highs in the 90s will extend north into northern Michigan and northern Wisconsin, with the 90s being common across the Midwest for much of this week.
When factoring in the heat index, many Midwesterners will feel temperatures in the triple digits, making conditions downright dangerous for long-term exposure. This includes places like Milwaukee, Chicago, St. Louis and Minneapolis.
Several daily record highs are possible by midweek, especially in the Ohio Valley where some highs in the mid-to-upper 90s are possible.
East
In the east, hotter air will begin to arrive Monday and will last most of the week for many.
Highs in the mid-to-upper 90s will be common, with triple-digit highs possible for several days in a row in the central Atlantic. Dangerous heat levels of 100 to 110 degrees are also expected in areas such as Washington, D.C., Philadelphia and Richmond, Virginia.
Several daily record highs are possible in the first half of the week along and west of the I-95 corridor from the Washington, D.C. metro to parts of Virginia and the eastern Great Lakes, before widespread record highs are expected from the Carolinas to New England by Thursday.
And overnight lows may struggle to fall much below 80 degrees in central Philadelphia, Baltimore and Washington, D.C.
Parts of New England and upstate New York may be hot at times, but they will avoid the worst of that prolonged heat wave this week.
(MORE: Danger of night heat)
South
While the South is accustomed to hot summers, the coming heat will be both persistent and oppressive.
Temperatures reached the 90s across much of the region this weekend, and the heat will continue throughout this week. Temperatures could even top 100 degrees in some places across both the Southern Plains and the Southeast from Virginia to the Carolinas.
Add to that the humidity in the South, and the heat index will exceed 100 from Texas to the Carolinas.
During this heat wave, the South, including parts of Florida and Texas, could see multiple daily high temperature records.
How long will the heat last?
Will this heat wave be in store for your Fourth of July weekend?
There is still some uncertainty this far into the future, as is often the case with long-term forecasts.
The latest computer models suggest the heat dome responsible for this heat wave may retreat west into the High Plains by the holiday weekend.
If that happens, there could be some relief coming to the East, especially New England, by the holiday weekend.
Some of our models are also forecasting the heat to ease in parts of the Midwest and possibly the South a week after the fourth holiday weekend.
Be sure to check back here as we continue to update the forecast and keep a close eye on the holiday weekend.
(MORE: 5 things you need to know to stay safe during the heat)
