Idaho has a temperate climate with warm summers and freezing winters.
Idaho has an average annual temperature of 49.1°F across all 10 cities, with approximately 487 mm of annual precipitation and average humidity of 61%. Temperatures peak in July and drop to their lowest in January, while rainfall is highest during winter months.
The warmest city is Caldwell with average July highs of 104.7°F, while Rexburg is the coldest with average January lows of -11.7°F. Humidity remains moderate throughout the year, especially during winter months, creating cold and dry conditions. These seasonal patterns make summer ideal for outdoor activities, while winters bring freezing conditions and heavy snowfall.
| Month | 🌤️ | High | Low | Avg | Humid % | Rain (mm) | Wind (m/s) | Solar (kWh/m²) |
|---|---|---|---|---|---|---|---|---|
| January | ❄️ | 43.5°F | 1.2°F | 22.5°F | 86% | 55 | 2.0 | 1.60 |
| February | ❄️ | 51.4°F | 6.3°F | 28.8°F | 79% | 45 | 2.2 | 2.60 |
| March | 🌤️ | 64.2°F | 17.1°F | 40.6°F | 70% | 50 | 2.3 | 3.90 |
| April | 🌤️ | 75.2°F | 23.9°F | 49.5°F | 62% | 42 | 2.3 | 5.30 |
| May | 🌤️ | 84.4°F | 29.7°F | 57.0°F | 57% | 49 | 2.2 | 6.40 |
| June | ☀️ | 92.7°F | 38.5°F | 65.5°F | 50% | 34 | 2.1 | 7.20 |
| July | 😎 | 99.1°F | 48.6°F | 73.8°F | 39% | 16 | 2.0 | 7.50 |
| August | 😎 | 98.1°F | 47.8°F | 72.9°F | 37% | 17 | 1.9 | 6.40 |
| September | ☀️ | 91.6°F | 36.3°F | 63.9°F | 42% | 24 | 1.9 | 5.00 |
| October | 🌤️ | 78.4°F | 24.8°F | 51.6°F | 55% | 36 | 2.0 | 3.30 |
| November | 🌤️ | 61.2°F | 14.4°F | 37.8°F | 72% | 55 | 2.1 | 1.90 |
| December | ❄️ | 45.7°F | 3.0°F | 24.3°F | 83% | 63 | 2.1 | 1.30 |
Showing average climate conditions across 45 years (1981–2025) · averaged across all 10 cities in Idaho
🧥 Pack heavy layers and prepare for snow — this is a Severe Winter destination.
🌤️ Limit midday outdoor exposure and stay hydrated — this is an intense Hot Summer.
☔ Rainfall is spread across the year with no sharply defined wet season.
Region-wide monthly averages across 10 cities · 1981–2025 · °F
Temperatures rise steadily from spring, peak in July, and gradually decline through autumn into winter.
These seasonal patterns make summer ideal for outdoor activities, while winters bring freezing conditions and heavy snowfall.
Region-wide monthly rainfall · 1981–2025 · mm/month
Monthly averages · 1981–2025
💧 Humidity peaks at 86% in January · annual avg 61%
The warmest year on record was 2025 (avg: 52.5°F), while the coldest year was 1985 (avg: 43.7°F).
Averaged across all 10 cities in Idaho · Last 10 years · °F
Averaged across all 10 cities in Idaho · Last 10 years · mm/year
🔥 hottest · ❄️ coldest · 🌧️ wettest
ℹ️ Values are averages across all 10 cities in Idaho for each year.
| Year | Min Temp | Avg Temp | Max Temp | Rainfall (mm) | Avg Humidity | Avg Wind |
|---|---|---|---|---|---|---|
2025 | 27.9°F | 52.5°F | 77.0°F | 517 | 60% | 2.1 m/s |
2024 | 25.7°F | 50.9°F | 75.9°F | 544 | 61% | 2.1 m/s |
2023 | 25.3°F | 49.1°F | 72.7°F | 528 | 64% | 2.0 m/s |
2022 | 22.8°F | 48.7°F | 74.7°F | 491 | 61% | 2.0 m/s |
2021 | 27.3°F | 52.0°F | 76.8°F | 452 | 57% | 2.1 m/s |
2020 | 25.3°F | 51.1°F | 76.8°F | 508 | 59% | 2.2 m/s |
2019 | 23.2°F | 47.5°F | 72.0°F | 467 | 63% | 2.1 m/s |
2018 | 25.7°F | 49.8°F | 73.9°F | 473 | 61% | 2.1 m/s |
2017 | 24.4°F | 48.2°F | 71.8°F | 639 | 65% | 2.0 m/s |
2016 | 25.9°F | 49.6°F | 73.4°F | 547 | 62% | 2.1 m/s |
Showing 1 to 10 of 45 years
All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.
