Nevada: The Driest U.S. State

By the Numbers

Nevada is the driest state in the U.S. with ~9 inches (229 mm) average annual precipitation (statewide average, 1991–2020 normals).

Why So Dry?

🌵 Climate Reality

• Desert types: Mojave (south), Great Basin (north)
• Humidity: Often <10% (summer afternoons)
• Evaporation: >100 in/yr (potential) vs. 9 in precip
• Extremes: Death Valley (CA border) — hottest/driest in NA

📊 Comparison (Annual Precip)

• Nevada: 9.0 in
• Utah: 12.2 in
• Arizona: 12.6 in
• Wyoming: 12.9 in
• New Mexico: 13.7 in
• US Average: 30.2 in

💧 Water Management

• Colorado River: 300,000 acre-ft allocation (Las Vegas = 90% dependent)
• Groundwater: Overdrafted basins; SGMA-style management emerging
• Conservation: SNWA "Cash for Grass," strict schedules, reuse
• Future: Aridification (climate change) = less runoff, more demand

🏙️ Population Paradox

Despite aridity, Nevada is fastest-growing state (2010–2020). Las Vegas metro = 2.3M. Water engineering enables growth—but sustainability is the 21st century challenge.