Heading into the last week of June, the Northeast will experience a two-day heat wave with dangerously high temperatures and humidity levels.
Specifically, hot weather that feels well over 100 degrees will cover the region on Monday, June 23 and Tuesday, June 24. In New Hampshire, the National Weather Service (NWS) of Gray, Maine has warned that the heat wave poses a risk of heat-related illness, issuing an extreme heat warning and watch for the state.
Here’s what to know about the heat wave in New Hampshire, as well as how to stay safe from heat stroke.
How long will the heat wave last in New Hampshire?
The NWS forecasts that temperatures on Monday and Tuesday will rise into the 90-100 degree range, with the heat index values reaching 100-105 degrees. Temperatures will be especially hot overnight Monday, with the heat peaking on Tuesday. Cooler temperatures will return during the second half of the week, with rain showers likely later this week and into the weekend.
Due to the extreme heat and humidity expected, the NWS has issued various warnings from now through Tuesday evening for the state of New Hampshire. The entire state is under a heat advisory, with an extreme heat watch issued for areas south of the mountains and an extreme heat warning issued in southern and western New Hampshire. Specifically, Sullivan, Cheshire, Merrimack and Hillsborough counties are under extreme warning, as they are expected to reach the highest temperatures in the state.
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Why is it so hot?
NWS Burlington Senior Service Hydrologist John Goff said that the heat is being caused by a “strong high-pressure system.”
“It’s basically sinking of air, and sinking is compressing, compressing the air and warming it,” he said. “The source of the air is coming from the southwestern United States, from the Central Plains and southwest. And so that area was already hot for several weeks. So that air is being pushed eastward for a few days across New England.”
How to stay safe from the heat
According to the NWS, the dangerous heat and humidity levels over the next couple days put all of New Hampshire at a major risk of heat-related illnesses, especially for sensitive groups. The NWS recommends the following precautionary measures:
Stay indoors in air conditioning and out of the sun.
Wear lightweight clothing.
Do not leave children or pets in unattended vehicles.
Reduce or reschedule strenuous activities until the coolest part of the day.
Check on relatives and neighbors.
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Symptoms of heat exhaustion and heat stroke
Common symptoms of heat exhaustion include dizziness, heavy sweating, thirst, weakness and nausea, according to the NWS. If these symptoms are experienced, the affected person should quickly move to a cooler area and sip cold water, calling for medical attention if symptoms do not improve.
Symptoms of heat stroke include extreme dizziness, confusion or even unconsciousness. The NWS warns that heat stroke is an emergency that can cause permanent disability or death, and emergency services should immediately be called for any of the above symptoms.
Margie Cullen contributed to this report.
This article originally appeared on Portsmouth Herald: NH weather: Head advisory issued as excessive heat moves in