How to read today's UV index
The UV index measures the strength of ultraviolet radiation at the ground, not how hot the air feels. Heat comes from infrared; UV can be high on a cool, bright day and still damage skin and eyes. Use the live number above as a planning signal before outdoor time.
Check the current value and today's peak. If the peak sits in the High or Very High range, schedule longer outdoor activity earlier or later, pack sunscreen, and prefer shade when the sun is overhead.
Plan your day with the next few hours
A short forecast window helps more than a single snapshot. Cloud cover can drop UV for an hour, then clear and push levels back up. If you are commuting, exercising, or taking children outside, glance at the next three hours and match protection to the highest expected stretch.
Skin type, medication, and altitude change how aggressively you should protect yourself. Fairer skin burns faster; higher elevations receive stronger UV. When conditions look elevated, default to clothing and sunscreen rather than waiting for a sunburn warning from your skin.
Why surroundings raise your UV dose
Surfaces bounce UV back toward you. Standing near reflective ground can mean a higher effective dose than the plain index suggests—especially at the beach or in snow.
WaterCan reflect a meaningful share of UV. Swimmers and boaters still need protection.
Dry SandBeach sand reflects UV upward, intensifying exposure for people sitting or walking nearby.
Fresh SnowSnow can reflect a large fraction of UV—alpine days often need sunglasses and SPF even when cold.
Limits of these readings
Values on this page are estimates for everyday sun-safety planning. Local clouds, shade, altitude, and time of day can move real exposure up or down. Readings are not medical advice and do not replace professional care if you have a skin condition or unusual reaction to the sun.
When unsure, protect more rather than less: shade, clothing, broad-spectrum sunscreen, and shorter midday sessions. Explore the blog for practical routines, guides for quick Q&A, or learn about this site.