Excessive heat creates health threat

The National Weather Service in Boise indicates some areas of southwest Idaho could approach or exceed all-time heat records. Please see the NWS video advisory: http://www.youtube.com/watch?v=F2VBmDsAwAc

National Weather Service
Heat is one of the leading weather-related killers in the United States, resulting in hundreds of fatalities each year. In the disastrous heat wave of 1980, more than 1,250 people died. In the heat wave of 1995 more than 700 deaths in the Chicago area were attributed to heat, making this the deadliest weather event in Chicago history. In August 2003, a record heat wave in Europe claimed an estimated 50,000 lives.

North American summers are hot; most summers see heat waves in one or more parts of the United States. East of the Rockies, summers tend to combine both high temperatures and high humidity, although some of the worst heat waves have been catastrophically dry.

NOAA's watch, warning and advisory products for extreme heat

Each National Weather Service forecast office issues the following heat-related products as conditions warrant:

Excessive heat outlooks are issued when the potential exists for an excessive heat event in the next three to seven days. An Outlook provides information to those who need considerable lead time to prepare for the event, such as public utility staff, emergency managers and public health officials. See the mean heat index and probability forecasts maps.

Excessive 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. A Watch provides enough lead time so that those who need to prepare can do so, such as city officials who have excessive heat event mitigation plans.

Excessive heat warning/advisories are issued when an excessive heat event is expected in the next 36 hours. These products are issued when an excessive heat event is occurring, is imminent, or has a very high probability of occurring. The warning is used for conditions posing a threat to life. An advisory is for less serious conditions that cause significant discomfort or inconvenience and, if caution is not taken, could lead to a threat to life.

How forecasters decide whether to issue excessive heat products
NOAA's hea- alert procedures are based mainly on Heat Index Values. The Heat Index, sometimes referred to as the apparent temperature is given in degrees Fahrenheit. 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. As an example, if the air temperature is 96°F and the relative humidity is 65 percent, the heat index--how hot it feels -- is 121°F. 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 two consecutive days.

Hazards of excessive heat
During extremely hot and humid weather the body's ability to cool itself is affected. 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 heat-related illnesses may develop.

Heat-related illnesses can range from heat cramps to heat exhaustion to more serious heat stroke. Heat stroke can result in death and requires immediate medical attention.

Factors or conditions that can make some people more susceptible to heat-related illnesses include age (older adults and young children), obesity, fever, heart disease, mental illness, poor circulation, prescription drug and alcohol use, and sunburn. Sunburn, caused by ultraviolet radiation from the sun, can significantly retard the skin's ability to shed excess heat.

Heat-related illness symptoms and first aid

Heat cramps

Symptoms:

  • Painful muscle cramps and spasms usually in legs and abdomen
  • Heavy sweating

First Aid:

  • Apply firm pressure on cramping muscles or gentle massage to relieve spasm.
  • Give sips of water, if nausea occurs, discontinue water

Heat exhaustion

Symptoms:

  • Heavy sweating
  • Weakness
  • Cool, pale, clammy skin
  • Weak pulse
  • Possible muscle cramps
  • Dizziness
  • Nausea and vomiting
  • Fainting
  • Normal temperature possible

First aid

  • Move person to a cooler environment
  • Remove or loosen clothing
  • Apply cool, wet cloths
  • Fan or move victim to air conditioned room
  • Offer sips of water. If nausea occurs, discontinue water. If vomiting continues, seek immediate medical attention.

Heat stroke (or sunstroke)

Symptoms:

  • Altered mental state
  • Possible throbbing headache, confusion, nausea, dizziness, shallow breathing
  • High body temperature (106°F or higher)
  • Skin may be hot and dry, or patient may be sweating
  • Rapid pulse
  • Possible unconsciousness

First Aid:

Heat stroke is a severe medical emergency. Summon emergency medical assistance 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 a water mister and fan or sponging
  • Use fan if heat index temperatures are below the high 90s
  • Use extreme caution
  • If temperature rises again, repeat process
  • DO NOT give fluids

Never leave children, disabled adults or pets in parked vehicles
Each year, dozens of children and untold numbers of pets left in parked vehicles die from hyperthermia. Hyperthermia is an acute condition that occurs when the body absorbs more heat than it can handle. Hyperthermia can occur even on a mild day. Studies have shown that the temperature inside a parked vehicle can rapidly rise to a dangerous level for children, pets and even adults. Leaving the windows slightly open does not significantly decrease the heating rate. The effects can be more severe on children because their bodies warm at a faster rate than adults.

Published 6-28-13