Project Trinetra / Preparedness / Extreme Heat Extreme Heat Heat is the #1 weather-related killer in the United States
8 things to do before · 8 steps during · 8 after · 5 questions answered
Last updated 2026-09-25 . Written by Project Trinetra, a program of the 501(c)(3) nonprofit Unravel The Love. It is not an official government publication and does not replace instructions from your local emergency authorities.
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Open the live map Before — Prepare for Extreme HeatHeat waves kill hundreds annually. Preparation and awareness save lives.
# Do this 1 Ensure air conditioning works or identify nearby cooling centers 2 Stock up on water and electrolyte drinks 3 Know the signs of heat exhaustion and heat stroke 4 Check on elderly neighbors and those without AC 5 Plan for pet safety — never leave animals in vehicles 6 Install window coverings or reflective film to reduce heat 7 Review medications — some increase heat sensitivity 8 Plan outdoor activities for early morning or evening only
During — During Extreme HeatMinimize exposure. Your body can only cool itself so fast.
# Step 1 Stay in air-conditioned spaces as much as possible 2 Drink water frequently — do NOT wait until you are thirsty 3 Avoid alcohol, caffeine, and sugary drinks — they dehydrate 4 Wear lightweight, light-colored, loose-fitting clothing 5 NEVER leave children, pets, or anyone in a parked vehicle 6 Limit outdoor activity to early morning (before 10am) or evening (after 6pm) 7 Take cool showers or use wet towels on neck, wrists, and forehead 8 If you feel dizzy, nauseous, or have a headache — get to cool area immediately and call 911
After — After a Heat WaveRecovery and prevention for the next heat event.
# Step 1 Continue hydrating for 24-48 hours after heat breaks 2 Check on vulnerable neighbors — heat effects can be delayed 3 Inspect home cooling systems for any strain or damage 4 Restock water and supplies for next heat event 5 Review your heat safety plan and update if needed 6 Report any heat-related infrastructure damage (melted roads, rail buckling) 7 Consider installing better insulation or shade structures 8 Seek medical care if lingering symptoms like fatigue or headache persist
Supplies specific to this hazard · Extra bottled water (1 gallon per person per day) · Electrolyte packets or sports drinks · Battery-powered fan · Sunscreen SPF 30+ · Wide-brimmed hat and sunglasses Questions people ask What are the signs of heat stroke vs heat exhaustion? Knowing the difference can save a life:
Heat Exhaustion (serious but treatable):
· Heavy sweating, pale/clammy skin · Nausea, dizziness, headache · Muscle cramps, weakness · Treatment : Move to cool area, loosen clothing, cool wet cloths, sip waterHeat Stroke (life-threatening — call 911):
· Body temp above 103°F · Hot, red, DRY skin (sweating has stopped)· Confusion, slurred speech, loss of consciousness · Treatment : Call 911 immediately. Cool the person rapidly — ice packs on neck, armpits, groin. Do NOT give fluids if unconscious.The key difference: heat exhaustion still sweats. Heat stroke stops sweating. Heat stroke is a medical emergency.
Full Extreme Heat guide — before, during and after → How do I stay cool without air conditioning? When AC isn't available during extreme heat:
· Go to a cooling center — libraries, malls, community centers (check local listings)· Use wet towels on your neck, wrists, and forehead — evaporation cools your body· Close blinds and curtains on sun-facing windows during the day· Create cross-ventilation : Open windows on opposite sides of the home at night when it cools· Use fans strategically : Place a bowl of ice in front of a fan for a DIY cooler· Stay on the lowest floor — heat rises· Avoid using the oven or stove — cook outside or eat cold mealsTake cool (not cold) showers throughout the day. Drink water constantly, even if you don't feel thirsty.
Full Extreme Heat guide — before, during and after → Who is most at risk during extreme heat? Some people are significantly more vulnerable to heat:
· Elderly (65+) : Bodies regulate temperature less efficiently· Infants and young children : Can't regulate body temp or ask for water· People with chronic conditions : Heart disease, diabetes, respiratory illness· People on certain medications : Diuretics, beta-blockers, antihistamines, and psychiatric medications all affect heat tolerance· Outdoor workers : Construction, agriculture, landscaping· People without AC or transportation to cooling centers Check on vulnerable neighbors at least twice a day during heat waves. Never leave children or pets in parked vehicles — car interiors can reach 140°F in minutes.
Full Extreme Heat guide — before, during and after → How much water should I drink during a heat wave? During extreme heat, your body needs much more water than normal:
· Drink at least 1 cup (8 oz) every 15-20 minutes when active in the heat· Don't wait until you're thirsty — thirst is a late signal of dehydration· Daily minimum : 1 gallon per person during extreme heat (double the normal recommendation)· Avoid alcohol, caffeine, and sugary drinks — they dehydrate you· Add electrolytes if sweating heavily — water alone can dilute sodium (sports drinks, electrolyte packets)Watch your urine color: pale yellow = good, dark yellow = dehydrated. Clear is actually too much — add electrolytes.
Full Extreme Heat guide — before, during and after → Is it safe to exercise outdoors in extreme heat? Generally no when heat index is above 104°F. Here's a guide:
· Below 90°F heat index : Exercise with caution, hydrate extra· 90-104°F : Only early morning (before 7 AM) or evening (after 7 PM). Reduce intensity 50%.· Above 104°F : Move exercise indoors. Risk of heat stroke is high even for fit athletes.If you must be outside:
· Wear light, loose, light-colored clothing · Take breaks every 15-20 minutes in shade · Drink water before, during, and after · Exercise with a partner who can recognize heat illness signs Acclimatization takes 1-2 weeks. Don't push hard during the first heat wave of the season.
Full Extreme Heat guide — before, during and after → Quick facts · Heat stroke stops sweating — if someone is hot but NOT sweating, call 911 immediately. · Drink 1 cup of water every 15-20 minutes during extreme heat. Don't wait until you're thirsty. · Never leave children or pets in parked vehicles — car interiors reach 140°F in minutes. · Check on elderly neighbors twice a day during heat waves — they're at highest risk. · Avoid alcohol and caffeine during heat waves — both dehydrate you faster. ← All preparedness guides
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