Rankings · Weather

The sunniest states

Average daily solar energy.

Global horizontal irradiance: the solar energy reaching a horizontal surface, in kilowatt-hours per square metre per day, averaged over years. It is a measurement rather than a description, and it is used here because sunny days are not published for every county while this is. It tracks cloud cover closely, so it answers how grey a place is — the Olympic Peninsula and Arizona sit at opposite ends. It also indicates what a rooftop solar array would produce. Modelled from satellite cloud observations at roughly four kilometres, then read at the county's population-weighted centre, so a large county with varied terrain is represented by where its people live rather than by its average.

  1. 1Arizona5.76 kWh/m²
  2. 2Hawaii5.66 kWh/m²
  3. 3New Mexico5.56 kWh/m²
  4. 4Nevada5.55 kWh/m²
  5. 5California5.20 kWh/m²
  6. 6Florida4.93 kWh/m²
  7. 7Utah4.78 kWh/m²
  8. 8Texas4.77 kWh/m²
  9. 9Colorado4.76 kWh/m²
  10. 10Louisiana4.64 kWh/m²
  11. 11Oklahoma4.62 kWh/m²
  12. 12South Carolina4.60 kWh/m²
  13. 13Mississippi4.58 kWh/m²
  14. 14Georgia4.55 kWh/m²
  15. 15Alabama4.53 kWh/m²
  16. 16North Carolina4.46 kWh/m²
  17. 17Idaho4.43 kWh/m²
  18. 18Kansas4.43 kWh/m²
  19. 19Wyoming4.43 kWh/m²
  20. 20Arkansas4.42 kWh/m²
  21. 21Tennessee4.30 kWh/m²
  22. 22Missouri4.25 kWh/m²
  23. 23Nebraska4.25 kWh/m²
  24. 24Virginia4.24 kWh/m²
  25. 25District of Columbia4.15 kWh/m²
  26. 26Kentucky4.13 kWh/m²
  27. 27Maryland4.13 kWh/m²
  28. 28Delaware4.11 kWh/m²
  29. 29South Dakota4.08 kWh/m²
  30. 30Iowa3.98 kWh/m²
  31. 31Indiana3.98 kWh/m²
  32. 32New Jersey3.98 kWh/m²
  33. 33Montana3.96 kWh/m²
  34. 34West Virginia3.96 kWh/m²
  35. 35Illinois3.93 kWh/m²
  36. 36Pennsylvania3.90 kWh/m²
  37. 37Connecticut3.89 kWh/m²
  38. 38Ohio3.89 kWh/m²
  39. 39New York3.88 kWh/m²
  40. 40Rhode Island3.87 kWh/m²
  41. 41Oregon3.84 kWh/m²
  42. 42Massachusetts3.82 kWh/m²
  43. 43Michigan3.80 kWh/m²
  44. 44Wisconsin3.80 kWh/m²
  45. 45Minnesota3.79 kWh/m²
  46. 46New Hampshire3.78 kWh/m²
  47. 47North Dakota3.76 kWh/m²
  48. 48Maine3.72 kWh/m²
  49. 49Vermont3.64 kWh/m²
  50. 50Washington3.56 kWh/m²

Not ranked, because this measure is not published for them: Alaska. Needs a county centroid, which Connecticut's planning regions do not yet have.

Put this map on your own site

Free to use. The chart names its source and links back, so it stays honest wherever it ends up.

<iframe src="https://movermath.com/embed/sunshine" width="100%" height="420" style="border:0" loading="lazy" title="Average daily solar energy by state"></iframe>

Source: NREL National Solar Radiation Database. · How this is built