Las Vegas Weather Radar & Live Heat, Monsoon & Dust Map

Las Vegas has a reputation for sunshine, and for most of the year it earns it — but the valley's weather is far more dramatic than its blue skies suggest. This is a desert city of extremes: blistering heat that tests records every summer, a short and volatile monsoon that detonates thunderstorms and dust storms over the basin, flash floods that turn dry washes deadly in minutes, and a long-running water crisis visible in the falling line of nearby Lake Mead. Knowing which of these is in play is what the live map helps you see.

The defining force: desert heat

Las Vegas sits in a low basin in the Mojave Desert, surrounded by mountains, with bone-dry ground that offers nothing to soften the sun. The result is some of the most intense urban heat in the United States. Summer highs sail past 110°F (43°C) routinely, and the city regularly flirts with its all-time records during the multi-day heat waves that stall over the Southwest under a heat dome.

The saving grace is the dryness. Because the air holds so little moisture, sweat evaporates freely and the body can shed heat — the reason a dry 110°F is survivable where a humid version would not be. But "dry" doesn't mean "safe." Prolonged extreme heat is still one of the deadliest weather hazards there is, and the longer a heat dome parks over the valley, the more dangerous it becomes.

The monsoon: a few volatile weeks

For most of the year Las Vegas is reliably dry. Then, roughly from July into September, the North American monsoon shifts the winds and drags tropical moisture up into the Southwest. The valley flips from arid to humid, and the afternoons turn volatile: thunderstorms build over the surrounding mountains and drift into the basin, bringing sudden downpours, lightning, fierce gusts and walls of blowing dust. It's the city's real rainy season, compressed into a few unpredictable weeks.

Flash floods and dust walls

Monsoon storms bring two distinctive desert hazards. The first is the flash flood. Sun-hardened desert ground sheds a sudden downpour almost like concrete, so the water races into the washes and channels that lace the valley, transforming a dry ditch into a violent torrent in minutes. Crucially, the rain that floods a wash may fall miles away on a distant mountain — the danger can arrive under a blue sky overhead.

The second is the dust storm. The same thunderstorm outflow that brings the gusts can lift loose desert soil into a towering wall of dust that rolls across the valley, dropping visibility to near zero. It's the same haboob phenomenon seen across the Southwest, and it can be as hazardous to drivers as the flooding.

The slow hazard: water

Behind the dramatic weather sits a slower story. Las Vegas draws most of its water from the Colorado River and nearby Lake Mead, and years of drought across the Southwest have pulled the reservoir down to historic lows — the pale "bathtub ring" on its shores a visible marker of the deficit. It's a different timescale from a monsoon storm, but it's the same desert climate, and it's the long-term backdrop to everything else.

Reading it on the live map

The valley's weather is a three-layer read:

• Gauge the heat. Turn on Temperature to see how extreme it's getting and whether a heat dome is settling in for a multi-day stretch.
• Catch the storms. In monsoon season, Radar shows thunderstorms building over the mountains and pushing into the basin — your warning for downpours and flash-flood risk in the washes.
• Spot the dust. Add Smoke & Dust (aerosol) to see blowing dust, which often races ahead of a monsoon storm as a brown-out wall.
• Remember the long game. The drought-and-water guide explains the slow drawdown of Lake Mead that frames the region's water future.

Temperature tells you how hot the valley is baking; radar and dust tell you when the monsoon is about to break the calm. In a place that looks like endless sunshine, that combination is what reveals the desert's sharper edges before they reach you.