"Excessive Heat Warning in Effect Through 8 p.m. Wednesday." So say the weather forecasts, but what does "excessive heat warning" mean?
Let's deal with the easy part - the warning. A "warning" is one step up from an "advisory" and is issued when conditions are considered dangerous. So, the first thing to know is that this could be dangerous for some people.
How about the heat part?
The precise definition of "excessive heat" varies according to the region, but typically occur when there is a combination of high heat and high humidity. The Center for Disease Control defines it as temperatures hover 10 degrees or more above the average high temperature for a region.
At certain temperatures, the human body can no longer maintain proper internal temperatures and one may experience heat cramps, fainting, heat exhaustion, or a heat stroke.
Much like a "wind chill" will tell you how cold it "really" is in the winter, weather folks use the heat index is used to measure the opposite - how hot it really appears. If the temperature is 90 degrees F. and the humidity is 60%, the heat index puts the apparent temprature then at 100 degrees. At 95 degrees F. with 60% humidity, it can feel like it is 114 degrees.
The elderly, the very young, and people with illnesses are most susceptible to a heat-related illness or death, but anyone doing strenuous work in the heat can experience problems. If you are at risk, or have a friend or neighbor who could use some help, here are some tips for staying cool.
TIPS - From the Center for Disease Control:
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"Drink Plenty of Fluids
During hot weather you will need to increase your fluid intake, regardless of your activity level. Don't wait until you're thirsty to drink. During heavy exercise in a hot environment, drink two to four glasses (16-32 ounces) of cool fluids each hour. Warning: If your doctor generally limits the amount of fluid you drink or has you on water pills, ask how much you should drink while the weather is hot. Don't drink liquids that contain alcohol, or large amounts of sugar—these actually cause you to lose more body fluid. Also avoid very cold drinks, because they can cause stomach cramps.
Replace Salt and Minerals
Heavy sweating removes salt and minerals from the body. These are necessary for your body and must be replaced. If you must exercise, drink two to four glasses of cool, non-alcoholic fluids each hour. A sports beverage can replace the salt and minerals you lose in sweat. However, if you are on a low-salt diet, talk with your doctor before drinking a sports beverage or taking salt tablets.
Wear Appropriate Clothing and Sunscreen
Wear as little clothing as possible when you are at home. Choose lightweight, light-colored, loose-fitting clothing. Sunburn affects your body's ability to cool itself and causes a loss of body fluids. It also causes pain and damages the skin. If you must go outdoors, protect yourself from the sun by wearing a wide-brimmed hat (also keeps you cooler) along with sunglasses, and by putting on sunscreen of SPF 15 or higher (the most effective products say "broad spectrum" or "UVA/UVB protection" on their labels) 30 minutes prior to going out. Continue to reapply it according to the package directions.
Schedule Outdoor Activities Carefully
If you must be outdoors, try to limit your outdoor activity to morning and evening hours. Try to rest often in shady areas so that your body's thermostat will have a chance to recover.
Pace Yourself
If you are not accustomed to working or exercising in a hot environment, start slowly and pick up the pace gradually. If exertion in the heat makes your heart pound and leaves you gasping for breath, STOP all activity. Get into a cool area or at least into the shade, and rest, especially if you become lightheaded, confused, weak, or faint.
Stay Cool Indoors
Stay indoors and, if at all possible, stay in an air-conditioned place. If your home does not have air conditioning, go to the shopping mall or public library—even a few hours spent in air conditioning can help your body stay cooler when you go back into the heat. Call your local health department to see if there are any heat-relief shelters in your area. Electric fans may provide comfort, but when the temperature is in the high 90s, fans will not prevent heat-related illness. Taking a cool shower or bath or moving to an air-conditioned place is a much better way to cool off. Use your stove and oven less to maintain a cooler temperature in your home.
Use a Buddy System
When working in the heat, monitor the condition of your co-workers and have someone do the same for you. Heat-induced illness can cause a person to become confused or lose consciousness. If you are 65 years of age or older, have a friend or relative call to check on you twice a day during a heat wave. If you know someone in this age group, check on them at least twice a day."
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There is more information available here: http://www.bt.cdc.gov/disasters/extremeheat/heat_guide.asp
I personally have a bit of a problem with the air-conditioning solution, as it ultimately adds heat to the planet and is part of the reason we are having these more-frequent heat moments, but I am also first to stand next to the freezer section at the supermarket, so I'm not one to go throwing stones (or ice cubes).
Stay cool, and check in on neighbors or friends who may need some help getting through the excessive heat period.