HeatSafe Day
A personal heat-safety planner that pulls NWS extreme heat warnings, your calendar, and your home AC status to flag dangerous outdoor windows in your day, route you to nearby cooling centers, and ping hydration nudges during peak heat hours.
Residents of Sun Belt cities (Phoenix, Las Vegas, Houston, Phoenix suburbs) who want to plan outdoor activities around heat waves
- Daily 'heat-safe window' forecast that scores each hour for safety using NWS warnings, humidity, and your scheduled outdoor activities
- Cooling-center locator with walking and driving directions, hours, and pet/caregiver policies pulled from city and county data
- Heat-vulnerable contact alerts — pings family members when medication or age moves a relative into higher risk for the day
- Wet-bulb-globe estimate combining ambient conditions with your exertion to warn before your day becomes medically unsafe
Phoenix has been trending on extreme heat warnings as temperatures routinely exceed 110°F and 430 heat-related deaths were logged in the Valley in 2025, yet NWS warnings give no personalized day-plan guidance.
Maricopa County logged 430+ heat-related deaths in 2025 with NWS issuing active Extreme Heat Warnings at 112-116°F and Phoenix hitting 100°F+ for 30% of 2024 — a large, recurring real-world problem in the target geography.NWS Phoenix Heat Page ↗Arizona heatwave 2025: Maricopa county heat horror: Hundreds dead as Arizona bakes in relentless heatwave ↗Climate change pushes Arizona into 'uncharted territory' with deadly heat ↗
The OSHA-NIOSH Heat Safety Tool is a free, government-backed app with hourly heat-index forecasts and OSHA/NIOSH recommendations — a credible direct competitor that already occupies the core 'personal outdoor heat planner' use case for $0.Heat Safety Tool App (OSHA-NIOSH) | CDC NIOSH ↗OSHA-NIOSH Heat Safety Tool - Heat.gov ↗OSHA-NIOSH Heat Safety Tool App - ClimaHealth ↗
Hard to monetize B2C: heat safety is treated as a public-health good, the closest comparable (OSHA-NIOSH) is free from a government source, and consumer willingness to subscribe for a heat planner is unproven — likely needs a B2B pivot (insurers, municipalities, employers) to extract revenue.OSHA-NIOSH Heat Safety Tool - Apps on Google Play ↗Heat Reports - Maricopa County Heat Surveillance ↗
Climate change is pushing Arizona into 'uncharted territory' with record-setting heat years on top of each other; extreme-heat exposure for Sun Belt residents is a worsening multi-decade secular trend, not a fad.Climate change pushes Arizona into 'uncharted territory' with deadly heat ↗Five climate tech solutions beating the heat ↗
All building blocks are accessible: the NWS API is free, key-less, GeoJSON-based, and exposes alerts/forecasts directly; calendar, smart-thermostat, and municipal cooling-center open data are widely available — the product is buildable by a small team.API Web Service - National Weather Service ↗Alerts Web Service - National Weather Service ↗Weather.gov API - FreeAPIHub ↗