Nampa has a temperate climate with warm summers and cold winters.
Temperatures peak in July and drop to their lowest in January, while rainfall is highest during winter months.
Humidity remains relatively low throughout the year, especially during winter months, creating cold and dry conditions.
| Month | 🌤️ | Avg High | Avg Temp | Avg Low | Record High | Record Low | Humid % | Rain (mm) | Wind (m/s) | Solar (kWh/m²) |
|---|---|---|---|---|---|---|---|---|---|---|
| January | ❄️ | 39.2°F | 31.8°F | 24.3°F | 63.9°F | -13.2°F | 78% | 41 | 2.2 | 1.68 |
| February | 🌨️ | 45.3°F | 36.4°F | 27.5°F | 69.6°F | -6.2°F | 70% | 33 | 2.4 | 2.68 |
| March | 🌨️ | 54.2°F | 43.3°F | 32.3°F | 79.2°F | 14.7°F | 62% | 38 | 2.4 | 4.04 |
| April | 🌨️ | 61.7°F | 49.4°F | 37.2°F | 90.3°F | 22.8°F | 55% | 32 | 2.4 | 5.54 |
| May | 🌤️ | 71.5°F | 58.4°F | 45.3°F | 101.1°F | 25.9°F | 49% | 38 | 2.3 | 6.67 |
| June | ☀️ | 81.9°F | 67.7°F | 53.6°F | 110.8°F | 36.3°F | 42% | 23 | 2.2 | 7.45 |
| July | 🌞 | 93.0°F | 77.5°F | 61.9°F | 110.8°F | 43.3°F | 33% | 8 | 2.1 | 7.65 |
| August | 🌞 | 91.3°F | 76.3°F | 61.3°F | 108.9°F | 40.6°F | 31% | 8 | 2.0 | 6.62 |
| September | ☀️ | 80.4°F | 66.5°F | 52.5°F | 106.7°F | 31.8°F | 36% | 14 | 2.0 | 5.21 |
| October | 🌤️ | 65.4°F | 53.4°F | 41.5°F | 95.0°F | 18.5°F | 48% | 23 | 2.1 | 3.51 |
| November | 🌨️ | 49.8°F | 40.6°F | 31.4°F | 76.8°F | 5.4°F | 64% | 38 | 2.2 | 2.02 |
| December | ❄️ | 38.9°F | 31.8°F | 24.7°F | 63.0°F | -10.7°F | 76% | 49 | 2.2 | 1.41 |
Showing average climate conditions across 45 years (1981–2025)
🧥 Expect frosty nights and below-freezing temperatures during this Cold Winter period.
🌤️ 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.
Monthly averages · 1981–2025 climate normals · °F
Temperatures rise steadily from spring, peak in July, and gradually decline through autumn into winter.
These seasonal patterns make summer pleasant for travel, while winters can bring frost and occasional snowfall.
Monthly rainfall · 1981–2025 seasonal trends · mm/month
Rainfall is concentrated in the winter months. Humidity stays relatively low (around 54%), peaking during winter months, which creates cold and dry conditions.
☔ Rainfall is spread across the year with no sharply defined wet season.
Monthly averages · 1981–2025
Across 45 years of records, Nampa's temperature has remained relatively stable over the past decade. Its hottest day reached 110.9°F in June 2015, and its coldest dropped to -13.2°F in January 2017. 2025 was the warmest year overall and 1993 the coolest.
The warmest year in Nampa's recorded history was 2025 (avg: 55.4°F), while the coldest was 1993 (avg: 48.9°F).
Average annual high/low · Last 30 years · °F
Total annual precipitation · Last 30 years · mm/year
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall (mm) | Avg Humidity | Avg Wind |
|---|---|---|---|---|---|---|---|---|
2025 🔥 | 67.3°F | 55.4°F | 43.5°F | 103.8°F | 5.2°F | 387 | 55% | 2.2 m/s |
2024 | 66.4°F | 54.7°F | 43.0°F | 108.5°F | -3.3°F | 464 | 54% | 2.2 m/s |
2023 | 64.4°F | 53.4°F | 42.6°F | 105.4°F | 7.5°F | 400 | 56% | 2.1 m/s |
2022 | 64.8°F | 53.2°F | 41.5°F | 106.7°F | 5.2°F | 363 | 52% | 2.1 m/s |
2021 | 67.3°F | 55.2°F | 43.3°F | 107.2°F | 4.8°F | 332 | 49% | 2.3 m/s |
2020 | 65.8°F | 54.0°F | 42.1°F | 104.9°F | 19.8°F | 356 | 51% | 2.2 m/s |
2019 | 63.7°F | 52.7°F | 41.5°F | 103.3°F | 13.8°F | 331 | 54% | 2.2 m/s |
2018 | 65.5°F | 54.0°F | 42.4°F | 108.9°F | 11.1°F | 268 | 51% | 2.2 m/s |
2017 | 63.7°F | 52.5°F | 41.4°F | 105.3°F | -13.2°F | 428 | 57% | 2.2 m/s |
2016 | 66.2°F | 54.3°F | 42.6°F | 103.3°F | 1.0°F | 261 | 52% | 2.3 m/s |
Showing 1 to 10 of 45 years
Based on 45 years of data (1981–2025), July is typically the hottest month in Nampa, Idaho, with average high temperatures around 93.0°F.
January is the coldest month in Nampa, with average low temperatures around 24.3°F.
December receives the most rainfall with approximately 49 mm, while July is the driest with 8 mm.
The highest recorded temperature was 110.9°F in June 2015. This is part of the historical record spanning 1981–2025.
The lowest recorded temperature was -13.2°F in January 2017.
This page covers 45 years of climate data from 1981 to 2025. As new data is added to the database the page automatically reflects the updated coverage.
Nampa receives the most sunlight in July with an average solar radiation of 7.65 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning and agriculture in Idaho.
All climate data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite and model data. It provides monthly averages for temperature, precipitation, humidity, wind speed, and solar radiation.
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.
