WEST LEBANON — The Upper Valley is bracing for a wave of extreme heat anticipated to last through Friday.
In a Tuesday advisory, the National Weather Service warned East Coast residents of dangerously hot temperatures starting Wednesday afternoon through Friday evening, with heat index values up to 110 forecast.
“Overnight low temperatures will only fall into the 70s, resulting in accumulated heat stress,” the advisory stated.
While libraries and other public spaces often serve as cooling shelters amid heat waves, Fourth of July weekend means several of them will be closed or have limited hours on Friday.
Medical emergencies related to heat are common in the summer months, said Dr. Ryan Gerecht, who serves as medical director for emergency management for Dartmouth-Hitchcock Medical Center.
“It’s certainly something that will present itself this weekend,” Gerecht said Tuesday by phone.
Heat-related illnesses typically account for 6% of emergency department volume during a period of extreme heat, a significant increase from what is usually zero, said Gerecht. Dartmouth’s emergency department averages 100 patients in a period of 24 hours, based on data from the last year.
Heat can exacerbate chronic illness, such as asthma, though symptoms are not always immediately attributed to heat, said Gerecht.
For heat exhaustion, the most common symptoms are dizziness, headache, fatigue, excessive sweating and nausea. Heat stroke follows the “same continuum,” said Gerecht, but with an eventual decrease in sweating, rapid heart rate and body temperature over 104 degrees Fahrenheit.
One key sign of heat stroke is an altered mental status.
Those who can’t self care or are experiencing severe symptoms should visit an emergency department, said Gerecht. Heat illness can be life threatening and requires time sensitive treatment
Treatment for heat exhaustion starts with simply putting the patient in an air conditioned environment, along with providing water and ice to naturally lower body temperature.
Patients suffering heat stroke would be triaged at the highest level at Dartmouth Hospital, and receive rapid cooling treatment through ice water immersion, and similar techniques.
For those who may be required to remain outside for extended periods during the advisory period, Gerecht suggests wearing light, loose clothing and shifting activity to early mornings or evenings to avoid the worst of the heat index.
Pre-hydration is also an important step.
“Start that outdoor activity in a state that you’re already well hydrated going into the event so that you’re not playing as much catch up as you get hotter,” said Gerecht.
Even then, frequent breaks are necessary, and for most, the recommendation is to avoid strenuous activity altogether.
The Vermont Department of Health provides a map of cooling shelters for those who do not have regular access to air conditioning. People may also dial 211 to find the nearest option.
As of Tuesday, Lebanon and New London had designated cooling centers on the New Hampshire side of the Upper Valley.
In general, libraries and community centers are air conditioned and open to the public. However, with the holiday weekend, some places are not operating under normal business hours for a Friday.
Gerecht advises people to be careful about the temperature inside vehicles, and to never leave a child or pet in the car under any circumstance.
“We see just tragic accidents involving rapidly rising temperatures inside cars,” said Gerecht.
For dog owners, daily walks are still an option, but there are extra steps to take to ensure safety, said RayLynn Bradigan, executive director of the Upper Valley Humane Society.
Along with avoiding the hottest midday period, it’s also important to check how hot the pavement is before heading out on a walk. Dirt roads and fields are an alternative, Bradigan said Monday by phone.
Owners should also make sure water is constantly available to their pets, said Bradigan, who also encouraged pets to exercise in water, such as a sprinkler. Heavy panting and lethargy are common indicators of overheating in dogs.
“Trust your gut. It’s never a situation you want to wish you had gotten help,” said Bradigan of contacting a vet with concerns.
Gerecht suggested that community members check on their elderly neighbors, friends and family members who don’t have air conditioning, as people aged 65 and older are at the highest risk of heat-related illness.
