Heat Wave Safety

Heat Waves, while not necessarily an annual occurrence, are fairly common in the NYC Metro Area. They are even more common in the urban corridor of Northeast New Jersey. Each year, usually from late June into August, the temperature rises above 90 degrees for a few days in a row. Some years more than others, the heat can become dangerous and oppressive.

As is the case with any severe or hazardous weather, understanding the phenomenon is the first step to preventing it from impacting you or your loved ones. Below, we break down the science of heat waves and how to prepare and react to them.

What is a heat wave?

While technically defined as a “prolonged period of abnormally hot weather”, the National Weather Service defines a heat wave as three straight days with temperatures of 90 degrees or higher. In the NYC Metro Area, heat waves occur almost every year with varying intensity. Every year or two, a more notable heat wave occurs where the duration is increased to three or four days.

How does a heat wave occur?

Typically, an area of large high pressure forms over the Central United States and expands eastward. When the pattern is favorable, the ridge expands and allows for warm and humid air to build underneath it. Once the high pressure is overhead, temperatures can climb well above normal for several days.

Heat Wave Preparedness Checklist

The most important thing to do during a heat wave is to stay cool and hydrated. If you know that a heat wave is coming, make sure you’re fully stocked up on extra water and means of hydration. Be aware of both the temperature and heat index – the heat index is the combination of temperature and dew point and can often be a more realistic interpretation of what the body feels.

Check your emergency disaster kit and be sure you’re stocked up on essentials. Have a plan in case of a power outage. Check on neighbors, children, the elderly and pets.

The National Weather Service issues three main heat-related products:

Excessive Heat Watch – Conditions are favorable for an excessive heat event to meet or exceed local Excessive Heat Warning criteria in the next 24 to 72 hours

Heat Advisory – Heat Index values are forecasting to meet locally defined advisory criteria for 1 to 2 days (daytime highs= 100-105° Fahrenheit)

Excessive Heat Warning – Heat Index values are forecasting to meet or exceed locally defined warning criteria for at least 2 days (daytime highs= 105-110° Fahrenheit)

The Heat Index is a measure of both temperature and humidity, and is an accurate depiction of what the air truly feels like to the body. The combination of temperature and moisture can lead to oppressive conditions and make breathing difficult, especially for sensitive groups.

First and foremost, keep yourself hydrated. Be sure to avoid any prolonged exposure to the sun. Keep a very close eye on all neighbors and check in with loved ones. Keep a close eye on children, the elderly, and pets. Never leave anybody or any pet unattended in a car or un-cooled household.

You can make your experience more pleasant by wearing very light clothing and avoiding any prolonged physical activity. Take frequent breaks. And if we didn’t mention it before, check on your animals.

Heat related illnesses are very serious, and the symptoms can often come quickly and without warning. See the list of illnesses, treatments and symptoms on the American Red Cross heat page – and most importantly, call your emergency hotline if you think you or a loved one is experiencing a heat related illness.