Sunniest U.S. Cities: NOAA Rankings by Annual Sunny Days

Based on National Oceanic and Atmospheric Administration (NOAA) climate normals (1991–2020), these U.S. cities record the most annual sunny days (clear + mostly clear sky cover):

Top 10 Sunniest Cities

1. Yuma, AZ — 320 days (90% of year)
2. Lake Havasu City, AZ — 319 days
3. Phoenix, AZ — 314 days
4. Tucson, AZ — 312 days
5. Las Vegas, NV — 310 days
6. El Paso, TX — 304 days
7. San Diego, CA — 283 days
8. Albuquerque, NM — 282 days
9. Fresno, CA — 278 days
10. Sacramento, CA — 276 days

What "Sunny Days" Means

NOAA defines a "clear day" as ≤30% average sky cover; "partly cloudy" = 30–70%. The figures above combine both categories. Yuma's 320 days = 88% clear/partly cloudy.

Regional Patterns

• Southwest dominance: 6 of top 10 in Arizona alone
• Rain shadow effect: Sierra Nevada blocks Pacific moisture from Nevada/Arizona
• Subtropical high pressure: Persistent sinking air suppresses cloud formation

Notable Exclusions

Honolulu (~271 days) and Key West (~259) rank lower due to tropical convection. Denver (~245) surprises many—high altitude doesn't guarantee sun.

Data source: NOAA NCEI Climate Data. Normals updated decennially.