Extreme heat resources and references


Heat-related emergencies are increasing each year in Colorado. Accelerating changes in our climate have led to a rise in human exposure to harmful temperatures and worsening air quality. Extreme heat events are increasing in duration, frequency, and intensity as a result of climate change. According to the National Center for Environmental Information, Colorado broke 350 temperature-related records and tied an additional 165 in 2023. Many of these events are due to burning fossil fuels, such as coal and gas. When we burn fossil fuels, we release carbon dioxide (CO2) into the atmosphere and CO2 builds up in the atmosphere and causes the earth’s temperature to rise.

High temperatures also worsen air quality, causing additional health concerns. While heat-related illnesses and deaths are preventable, many people still succumb to illnesses caused by extreme heat each year. Identifying populations that are more vulnerable to extreme heat is an important strategy for preventing heat-related emergencies. Furthermore, Indoor heat exposure is a major contributor to heat-related deaths in older adults. The EPA states that elderly people spend 90% of their time indoors, therefore maintaining an appropriate indoor air temperature is important.


Persons most at risk

While everyone is susceptible to heat-related illnesses (ranging from a mild heat rash to a severe heat stroke),  some people are more at risk of experiencing a heat-related emergency. These populations include older adults (age 65+), persons with pre-existing chronic medical conditions or mental health conditions, infants and children, persons who are pregnant, outdoor workers, athletes, and persons with low income. The  medical conditions that are more vulnerable to heat effects include those with:

  • Cardiovascular Conditions
  • Respiratory Conditions
  • Diabetes
  • Obesity
  • Mental Illness
  • Persons with dementias

Heat.gov provides additional information about the risks to these populations.

Common medication risks 

Common medications may increase the dangers of heat waves. Some over-the-counter and prescription drugs may interfere with sweat production, alter the body’s internal thermostat, or make dehydration more likely — with potentially serious consequences. View the medication and heat infographic.

A few common medications are listed below

  • Antidepressants like selective serotonin reuptake inhibitors, or SSRIs, may increase sweating, increasing the risk of dehydration. Others, like tricyclic antidepressants, or TCAs, may decrease sweating, making it harder to cool off.
  • Antipsychotics may impair sweating and alter the body’s internal thermostat. 
  • Anticholinergic drugs, a large category of medications commonly used to treat an array of conditions such as urinary incontinence, overactive bladder, allergies, and Parkinson’s disease, may interfere with sweating and the body’s internal thermostat. They may also reduce blood flow to the skin.
  • Diuretics and ACE inhibitors taken by patients with heart disease can cause dehydration, affect kidney function, and limit the body’s ability to redirect blood flow.
  • Insulin and some other diabetes medications can lose their effectiveness in hot weather.

Dehydration may also pose risks by increasing the blood levels of some medications, such as lithium, a mood stabilizer. Even slight increases can lead to toxic effects ranging from tremors and weakness to agitation, confusion, and even death.

Extreme heat events can challenge healthcare operations as individual facilities increase use of energy, power outages, damage to highways and roads, and an increased demand for essential services like emergency hospital services, ambulance services and security. We encourage all healthcare providers and agencies to include heat-specific planning in their emergency planning efforts to ensure clients’, residents’, and patients’ safety.

Key elements to include:

  • Administrative procedures to meet emergency/surge staff capacity needs.
  • Staff training on heat-health risk information.
  • Steps to follow to keep your clients, residents, and patients cool and comfortable.
  • Emergency cooling options (air-conditioned rooms, fans, ice-water baths/showers).
  • Identify the need for backup generators, during possible power brown-outs/black-outs.
  • Plan for evacuation if the temperature inside becomes uncomfortable.

Mitigation Actions

Some important actions you can take prior to the summer season to prepare and/or respond to direct and indirect impacts of extreme heat include:

  • Review HVAC-system/air conditioner vulnerabilities or limitations with engineering/facility staff, have backup systems identified and/or contracts for additional cooling capabilities. Don’t wait until an extreme heat event to check your systems.
  • Review additional critical systems that may be impacted by high temperatures, including communications and IT systems.
  • Review prevention and emergency guidelines with staff - this increases effectiveness.
  • Review strategies for supporting most vulnerable clients, residents, and patients.
  • Review evacuation planning in case of power loss or HVAC malfunction.
  • Maintain awareness of heat risk forecasts during summer months: Check out the many National Weather Service’s Heat Forecast and Tools.
  • Maintain inventory of key supplies and plans to rapidly expand capabilities such as ice and fuel. 
  • Encourage staff to review their personal and home emergency preparedness plans ready.

If your health facility or agency is anticipating or experiencing or a high-risk-level extreme heat event:

Residential Facilities
  • Consult your facility’s emergency plan.
  • Notify engineering/facility staff as early as possible of additional power needs.
  • Review evacuation plans, and ready staff in case of power outages or cooling system failure. Make sure your transportation is in good working order.
  • Monitor indoor temperatures. Increase frequency of patient observations, especially of those at high risk. 
  • Ensure your staff is trained on the signs of heat-related illness, and how to respond.
  • Monitor the weather and heat index National Weather Service’s Heat Forecast and Tools.
  • Create specific cooling areas within your building during power loss or cooling system failure; if you are situated in a high-rise building, be prepared to move individuals from top floors to lower floors (Remember, heat rises!).
  • Implement strategies to mitigate extreme heat health impacts on patients, residents, and staff by increasing opportunities for hydration and cooling, canceling outdoor activities, frequent breaks, shifting schedules to minimize exposure to mid-day and evening heat. 
  • Implement supply conservation strategies based on anticipated or current shortages (ice, fuel, etc.).
  • Keep medications cool. 
  • Ensure meals with high water content are prepared and that spoiled food is discarded.
  • Understand the potential side-effects of medications, and carefully review the drugs that vulnerable patients are taking; and consult with a physician to consider optimum dosing during periods of hot weather.
  • Take appropriate steps to care for clients/residents/patients who experience heat-related illness with fluids, cooling, fanning, observation, and transfer if necessary to the emergency departments or hospitals.
  • Notify the Health Facilities and Emergency Medical Services Division to report an unusual occurrence, activation of your Emergency Operations Plan (EOP), or if you are evacuating your location.
  • When temperatures are forecast to be high-risk or very-high risk for most of the population, check in with key partners, begin upstaffing preparations, and alerting relevant leadership regarding immediate or anticipated activation of emergency operations/coordination center.
  • Consider potential heat/humidity impacts in operating rooms. Reschedule surgeries as necessary.
  • Consider accelerating discharges by reviewing patients ready for or awaiting discharge.

Home Health Providers and Patients Living Independently
  • Develop plans with clients, patients and their families for safe home care in the heat, including redundant plans for keeping loved ones cool if they experienced power outages. This is especially true for those who live in small, non-air-conditioned public housing units that are under older building codes. 
  • During extreme heat events, check in on clients and patients. A lot of these residents are older and may be taking medications that put them at higher risk.
  • Identify cooling centers, which are an important resource during extreme heat events and are especially critical for houseless individuals or those without adequate cooling in their homes. In Colorado: 
    • Contact local 2-1-1 for assistance and referrals to cooling centers.
    • Check with local news sources on openings of select cooling centers.



Temperature extremes

Persons who experience vulnerabilities

Home health clients and patients living on their own

  • Indoor heat exposure is a major contributor to heat-related deaths in older adults. The EPA states that elderly people spend 90% of their time indoors, therefore maintaining an appropriate indoor air temperature is important.

  • Establishing A Heat Action Plan for Patients, from americares.org/ClimateClinics.


Planning for utility outages


What is the heat island effect?

Urban centers tend to have a high density of buildings, paved roads and parking lots—all of which absorb and retain heat.Colorado’s green spaces such as parks, hiking trails and golf courses, in contrast, reduce heat levels in neighborhoods by lowering surface and air temperatures through evapotranspiration. Mature trees and other natural features provide shade, deflect the sun's radiation and release moisture into the atmosphere. As heat waves become more frequent and intense, cities are experiencing higher nighttime and mean temperatures compared with areas that have a lot of green space.This is commonly called the heat island effect. According to the CDC, urban heat islands, combined with an aging population and increased urbanization, are projected to increase the vulnerability of urban populations to heat-related health impacts in the future.