Temperatures are expected to be in the upper 90’s with some 100’s possible this week. Here is what you should know about dealing with the heat.
Know the difference between a Heat Advisory, Excessive Heat Watch, and Excessive Heat Warning?
NWS Heat Watches, Warnings and Alvisories
EachNational 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 illness 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 illness 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.
NWS Heat Index
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.
Heat exhaustion -vs- Heat Stroke
NWS Heat Safety: Common Heat Illnesses, Heat Exhaustion and Heat Stroke
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. Click on the infographics below for a full size version.
Heat cramps may be the first sign of heat-related illness, and may lead to heat exhaustion or stroke.Symptoms:
Painful muscle cramps and spasms usually in legs and abdomen
Apply firm pressure on cramping muscles or gently massage to relieve spasm.
Give sips of water unless the person complains of nausea, then stop giving water
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.
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.