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Millions of people in the northern United States are under heat alerts as an expanding high pressure system, also known as a heat dome, is forecast to push temperatures in the Northeast into the triple digits just as the arrival of the astronomical summer.
This will bring sweltering heat to major cities from Chicago to Detroi and major urban centers along the Interstate 95 corridor on the East Coast this weekend.
The peak of this heat wave will be Sunday through Thursday, when hundreds of millions of Americans will experience temperatures ranging from a few degrees above average to 20 degrees above average.
While relatively few places may reach the 100-degree mark, the combination of high temperatures and high humidity levels will make the wind chill significantly hotter.
Heat indices, which measure the temperature felt by the human body taking into account humidity, are forecast to reach triple digits in many areas.
Highs next Tuesday.
(Meteo Channel)
Among the areas expected to be affected are Denver, Chicago, Detroit, Pittsburgh, Philadelphia, New York and Washington.
In Denver, temperatures are forecast to exceed 90 degrees Fahrenheit (32 °C) on Thursday and exceed 100 degrees Fahrenheit (38 °C) on Friday. Temperatures will remain in the triple digits in Denver on Saturday.
Heat index next Tuesday.
(Meteo Channel)
New York City has only reached the 100-degree threshold three times during the month of June, while Philadelphia has done so nearly a dozen times, with the most recent case occurring in the mid-1990s.
The National Weather Service is expected to issue a series of heat-related alerts for the Northeast in the coming days, but a heat advisory and extreme heat warning have already been issued for millions of people from Colorado to the Canadian border in Minnesota.
The alerts are intended to warn residents about the dangers of prolonged exposure to high heat, which can lead to serious health consequences such as heat exhaustion, heat stroke and dehydration.
Heat recommendations.
(Meteo Channel)
Heat waves pose a particularly high risk to vulnerable populations, including children, the elderly, outdoor workers and those without access to air conditioning.
In communities with heat response plans, cooling centers are generally opened for residents to take advantage of when temperatures reach dangerous levels.
Temperatures are expected to return to more typical levels in late June and early July as the ridge of high pressure moves eastward, allowing frontal boundaries to move in, which will help induce more cloud cover and rainfall.
The heat is not likely to go away for long, as the hottest days of the season usually occur in mid to late July , when the effects of direct sunlight and solar radiation for the year are felt throughout the northern hemisphere.
