About SunScope
See the sun the way your skin does.
What is SunScope?
SunScope is a free outdoor thermal comfort forecast that goes well beyond standard air temperature. Most weather apps tell you it's 12 °C and leave you to guess whether that means a t-shirt or a heavy coat. SunScope combines air temperature, humidity, wind speed, and solar radiation into a single felt temperature — so you know what to actually expect when you step outside.
The core calculation is the Universal Thermal Climate Index (UTCI), a peer-reviewed biometeorological standard developed by Bröde et al. (2012) and used globally in heat-health warning systems. On top of that, SunScope builds its own SunSoak index — layering a rain and snow penalty, a Solar Model that adjusts the solar and thermal load for your surroundings, and the full radiant heat absorbed from surrounding surfaces. One number that honestly answers: what will my body actually feel out there?
Forecast data is sourced in real time from Open-Meteo, a free and open-source weather API drawing on ECMWF and national meteorological services, with air quality, visibility, and pollen from the Copernicus CAMS forecast. The forecast refreshes automatically every five minutes and is available for any location worldwide.
Explore the details
This guide is split into focused sections. Pick the one you're after — or work through them in order for the full picture of how SunScope turns raw weather data into an honest felt-temperature forecast.
What SunSoak is and how it's built on top of UTCI — the precipitation penalty, the Solar Model that adapts to eight different surroundings, and mean radiant temperature from the sun and surfaces around you.
The curated column sets — Basic, Home, Vehicle, Temps, Show All and Custom — plus the Places, Activities and Work dropdowns, each tailored to a specific situation.
Every column in the forecast table explained in plain language, from Air and Shade Air through to Lightning Potential, air quality, pollen, and SunSoak.
The physics-based temperature models: how hot a parked vehicle gets, how warm a building stays indoors without air conditioning, and how sun-baked urban concrete becomes.
The sky scope, day-strip weather icons, weather-event banners and popups, and the "What's Coming" cosmic events almanac.
How SunScope maps every SunSoak value to a colour-coded thermal stress band, from Polar cold through Comfortable to Extreme heat.
Frequently asked questions
Got a specific question — about UTCI, the SunSoak index, UV and sunburn times, how hot a parked car or pavement really gets, keeping your home cool without air conditioning, air quality, pollen, or soil and farming data? Our dedicated FAQ page answers the most common questions in plain language, grouped by topic.
Get in touch
SunScope is an independent project. If you have feedback, spotted a bug, or are interested in using SunScope data for your business or website, feel free to reach out via hello@sunscope.net.