It is NEVER safe to leave a toddler, disabled person or pet locked in a car, even in the winter. The first toddler death in 2018 occurred in February! Cars can heat up quickly when left in the sun. Find out more.
North American summers are hot. Sometimes spring and fall temperatures reach dangerous levels as well. Most summers see heat waves in one or more parts of the United States. Heat is one of the leading weather-related killers in the United States, resulting in hundreds of fatalities each year and even more heat-related illnesses. In addition to the resources below, OSHA offers a free OSHA Heat Safety App for both Android and iPhone.
This website is designed to inform you about the health dangers of heat, prepare you for excessive heat events, and tell you what to do during an excessive heat wave. You will find vital information about the dangers of leaving children, pets or anyone with limited mobility alone in a car even for a few minutes in what might seem like mild weather. Children locked in cars have died in December and in 70 degree weather, even with a window left open a little. You also will find information about protecting yourself from excessive heat, educational materials and specfics on how the National Weather Service keeps you aware of potentially dangerous situations. NWS tries make learning fun with games and activities to help educate your children about the dangers of heat and provide you with links for more information.
Each National Weather Service Forecast Office issues some or all of the following heat-related products as conditions warrant. NWS local offices often collaborate with local partners to determine when an alert should be issued for a local area. For instance, residents of Florida are much more prepared for 90°F+ weather than residents in Alaska.
- Excessive Heat Warning—Take Action! An Excessive Heat Warning is issued within 12 hours of the onset of extremely dangerous heat conditions. The general rule of thumb for this Warning is when the maximum heat index temperature is expected to be 105° or higher for at least 2 days and night time air temperatures will not drop below 75°; however, these criteria vary across the country, especially for areas not used to extreme heat conditions. If you don’t take precautions immediately when conditions are extreme, you may become seriously ill or even die.
- Excessive Heat Watches—Be Prepared! Heat watches are issued when conditions are favorable for an excessive heat event in the next 24 to 72 hours. A Watch is used when the risk of a heat wave has increased but its occurrence and timing is still uncertain.
- Heat Advisory—Take Action! A Heat Advisory is issued within 12 hours of the onset of extremely dangerous heat conditions. The general rule of thumb for this Advisory is when the maximum heat index temperature is expected to be 100° or higher for at least 2 days, and night time air temperatures will not drop below 75°; however, these criteria vary across the country, especially for areas that are not used to dangerous heat conditions. Take precautions to avoid heat illness. If you don’t take precautions, you may become seriously ill or even die.
- Excessive Heat Outlooks are issued when the potential exists for an excessive heat event in the next 3-7 days. An Outlook provides information to those who need considerable lead-time to prepare for the event.
The Heat Index is a measure of how hot it really feels when relative humidity is factored in with the actual air temperature. To find the Heat Index temperature, look at the Heat Index Chart above or check our Heat Index Calculator. As an example, if the air temperature is 96°F and the relative humidity is 65%, the heat index–how hot it feels–is 121°F. The red area without numbers indicates extreme danger. The National Weather Service will initiate alert procedures when the Heat Index is expected to exceed 105°-110°F (depending on local climate) for at least 2 consecutive days.
NWS also offers a Heat Index chart for area with high heat but low relative humidity. Since heat index values were devised for shady, light wind conditions, exposure to full sunshine can increase heat index values by up to 15°F. Also, strong winds, particularly with very hot, dry air, can be extremely hazardous.
During extremely hot and humid weather, your body’s ability to cool itself is challenged. When the body heats too rapidly to cool itself properly, or when too much fluid or salt is lost through dehydration or sweating, body temperature rises and you or someone you care about may experience a heat-related illness. It is important to know the symptoms of excessive heat exposure and the appropriate responses. The Centers for Disease Control and Prevention provides a list of warning signs and symptoms of heat illness, and recommended first aid steps. Some of these symptoms and steps are listed below.
–Heat Exhaustion Symptoms:
Cool, pale, clammy skin
Fast, weak pulse
Possible muscle cramps
Nausea or vomiting
Move person to a cooler environment. Lay person down and loosen clothing. Apply cool, wet cloths to as much of the body as possible. Fan or move victim to air conditioned room. Offer sips of water, If person vomits more than once, seek immediate medical attention.
–Heat Stroke Symptoms:
- Altered mental state
- One or more of the following symptons: throbbing headache, confusion, nausea, dizziness, shallow breathing
- Body temperature above 103°F
- Hot, red, dry or moist skin
- Rapid and strong pulse
- Faints, loses consciousness
- Heat stroke is a severe medical emergency. Call 911 or get the victim to a hospital immediately. Delay can be fatal.
- Move the victim to a cooler, preferably air-conditioned, environment.
- Reduce body temperature with cool cloths or bath.
- Use fan if heat index temperatures are below the high 90s. A fan can make you hotter at higher temperatures.
- Do NOT give fluids.