Following a break in high humidity in some areas and a reprieve of 90-degree Fahrenheit temperatures in others, both will build back into the northeastern United States as this week progresses.
The sharp southward dip in the jet stream that helped to usher in cooler and less humid air, along with gusty winds, will lift northward. As this happens, more typical light summertime breezes are in store.
As the common saying goes, “It’s not the heat, but the humidity.”
Just enough of a southerly breeze will develop to allow humidity levels to climb and daily high temperatures to trend upward into the Fourth of July and Friday.
Even though high temperatures in many areas may only trend upward by 5 to 8 degrees in most areas, the uptick in humidity will push AccuWeather RealFeel® Temperatures significantly higher.
The RealFeel Temperature is a more realistic interpretation of how hot the weather feels to the body. This measure incorporates additional factors beyond temperature and humidity levels, including wind and sunshine.
RealFeel Temperatures are forecast to range between 90 and 100 as far north as much of upstate New York state and New England during the middle to latter part of this week.
However, RealFeel Temperatures will approach 100 to 105 in some of the major mid-Atlantic cities, including Washington, D.C., and Richmond, Virginia.
“By far, the most dangerous conditions due to heat will be experienced in the Southeast states this week,” according to AccuWeather Senior Meteorologist Brett Anderson.
Taking breaks from the heat and staying hydrated will be essential whether on vacation, working outdoors or cooking without air conditioning in the kitchen.
From Tuesday through Friday, necessary strenuous activity should be avoided during the afternoon hours, when the sun is high in the sky and temperatures are at their peak.
The conditions much of this week will make for fine beach and swimming weather, but there are likely to be thundery consequences as the week progresses.
Along with the uptick in humidity will come spotty thunderstorms at first. A couple of wrinkles in the lifting jet stream can allow a thunderstorm or two to cross the region during Tuesday and Wednesday.
However, by Independence Day, more general thunderstorm activity is anticipated over the mid-Atlantic region as well as the central Appalachians and the eastern Great Lakes.
While there is a better than 50/50 chance of a thunderstorm in these areas, the chance will decrease substantially farther to the northeast.
At this time, it appears that much of central and eastern New England, including Boston, will be free of rain on the Fourth of July.
“It is possible that storms stay south and west of New York City during Thursday evening fireworks,” according to AccuWeather Senior Meteorologist Dave Dombek.
For those taking a dip in the Atlantic, storms typically avoid the beaches during the daytime, due to a sea breeze. As the sea breeze weakens in the evening, dwindling thunderstorms may then make their way to the ocean.
Surf temperatures range from a chilly 60 in southern Maine to near 80 in southeastern Virginia.
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