Boise weather by month & the best time to visit
United States · regional city · Mediterranean climate
The best time to visit Boise is September — its sunniest month (Sunshine Score 94/100), with June and May close behind. Boise averages about 2,989 hours of sunshine a year. Daytime highs around 27°C / 81°F and roughly 14 mm of rain in September.
When is the best time to visit Boise?
For sunshine, the best time to visit Boise is September, then June and May. The dullest month is January (0/100, 51 mm of rain). The full month-by-month picture is in the table below.
How sunny is Boise?
Boise gets a lot of sun: around 2,989 hours a year. 94 Sunshine Score points separate September (94) from January (0), so the month you pick matters. It ranks #89 of 580 destinations in United States for annual sunshine, above the national median of 2,279 hours. Rain has a clear season: the wettest stretch, around December, carries about 40% of the annual 390 mm.
Sunshine Score by month
| Month | Score | Day high | Night low | Rain | UV |
|---|---|---|---|---|---|
| January | 0 | 3° / 37°F | -4° / 25°F | 51 mm | 1 |
| February | 0 | 6° / 43°F | -2° / 28°F | 36 mm | 2 |
| March | 29 | 12° / 54°F | 1° / 34°F | 47 mm | 4 |
| April | 60 | 16° / 61°F | 4° / 39°F | 35 mm | 5 |
| May | 90 | 22° / 72°F | 9° / 48°F | 38 mm | 7 |
| June | 92 | 28° / 82°F | 13° / 55°F | 23 mm | 8 |
| July | 67 | 35° / 95°F | 19° / 66°F | 7 mm | 9 |
| August | 76 | 34° / 93°F | 18° / 64°F | 7 mm | 8 |
| September | 94 | 27° / 81°F | 13° / 55°F | 14 mm | 6 |
| October | 76 | 18° / 64°F | 6° / 43°F | 27 mm | 4 |
| November | 7 | 9° / 48°F | 0° / 32°F | 40 mm | 2 |
| December | 0 | 3° / 37°F | -4° / 25°F | 65 mm | 1 |
Nearest destinations
Head-to-head
How Boise compares month by month: Boise vs Pasco · Boise vs Redmond · Boise vs Idaho Falls · all comparisons
Boise: questions and answers
What kind of destination is Boise?
Boise is a regional city in United States at 867 m elevation with a Mediterranean climate.
How many hours of sunshine does Boise get a year?
Boise gets about 2,989 hours of sunshine a year, at its best around September.
When is the best time to visit Boise?
The sunniest time to visit Boise is September, when the Sunshine Score peaks at 94/100 (with June and May close behind). Expect daytime highs around 27°C / 81°F.
What is the least sunny month in Boise?
January is the least sunny month in Boise, scoring 0/100 with about 51 mm of rain.
How strong is the sun in Boise?
The typical midday UV index in Boise peaks around 9 (very high) in July, easing to about 1 (low) in January. Month-by-month midday UV values are in the UV column of the table on this page.
Put the Boise sunshine badge on your site
A compact badge showing Boise's sunshine at a glance — free to embed under CC BY 4.0. Paste this wherever you'd like it to appear:
Live preview — this is exactly what your readers see: