Caldwell, Idaho Weather History

Idaho, United States  •  45 yrs data 📍 43.6880°N, 116.6977°W
°F / °C
☀️

Quick Climate Facts

(1981 – 2025)
Hottest Month
🔥
Jul
Avg 78.2°F
Min 51.8°F
Max 104.7°F
Coldest Month
❄️
Jan
Avg 30.9°F
Min 10.7°F
Max 51.1°F
Wettest Month
🌧️
Dec
49 mm
Driest Month
🏜️
Jul
8 mm
Most Humid
💧
Jan
78%
Least Humid
🌬️
Aug
31%
Highest Ever
🌡️
110.9°F
Jun 2015
Lowest Ever
🧊
-13.2°F
Jan 2017
Monthly Climate Data
Month 🌤️ High Low Avg Humid % Rain (mm) Wind (m/s) Solar (kWh/m²)

Showing average climate conditions across 45 years (1981–2025)

🌍 Weather in Caldwell Across Seasons

❄️ Winter in Caldwell

January is Caldwell's coldest month, with average lows reaching 10.8°F.
🌡️ December to February (avg)  ·  13.1°F54.5°F

🧥 Pack heavy layers and prepare for snow — this is a Severe Winter destination.

☀️ Summer in Caldwell

Summer temperatures in Caldwell peak in July, climbing to 104.7°F.
🌡️ June to August (avg)  ·  48.2°F102°F

🌤️ Limit midday outdoor exposure and stay hydrated — this is an intense Hot Summer.

🌧️ Rainiest Period in Caldwell

Caldwell sees its highest rainfall in December, receiving approximately 49 mm of precipitation.
🌧️ December to March (avg)  ·  up to 49 mm

☔ Rainfall is spread across the year with no sharply defined wet season.

📅 Monthly Averages

🌡️ Temperature Patterns

Monthly averages · 1981–2025 climate normals · °F

🌡️ Caldwell Monthly Temperature Guide

Jul is the hottest month in Caldwell, with average highs reaching 104.7°F, while Jan is the coldest with lows dropping to 10.7°F.

Temperatures rise steadily from spring, peak in Jul, and gradually decline through fall into winter.

These seasonal patterns make summer ideal for outdoor activities, while winters bring freezing conditions and heavy snowfall.

🌧️ Rainfall Distribution

Monthly rainfall · 1981–2025 seasonal trends · mm/month

💨 Humidity & Wind Speed

Monthly averages · 1981–2025

💧 Rainfall & Humidity in Caldwell

Caldwell receives its highest rainfall in Dec, while humidity peaks during winter months.
🌧️ Wettest: Dec — 49 mm ☀️ Driest: Jul — 8 mm

💧 Humidity peaks at 78% in Jan · annual avg 54%

🌍 Climate Summary

Avg Annual Temp:54.9°F
Avg Annual Rainfall:345 mm
Avg Humidity:54%
Data Period:1981 – 2025

Caldwell Climate Overview

Caldwell has a warm temperate climate with warm summers and freezing winters.

Temperatures peak in Jul and drop to their lowest in Jan, while rainfall is highest during winter months.

Humidity remains relatively low throughout the year, especially during winter months, creating cold and dry conditions.

📈 Yearly Trends

The warmest year in Caldwell's recorded history was 2020 (avg: 58.1°F), while the coldest year was 1985 (avg: 49.8°F), based on annual average temperatures.

📊 Key Climate Trends

🌡️ Annual Temperature Trend

View Range:

Average annual high/low · Last 10 years · °F

Caldwell's temperatures has remained relatively stable over the past decade. The highest recorded temperature reached 110.9°F in Jun 2015, while the lowest dropped to -13.2°F in Jan 2017.

🌧️ Annual Precipitation

View Range:

Total annual precipitation · Last 10 years · mm/year

Annual rainfall in Caldwell shows noticeable variation. Rainfall has increased noticeably in recent years compared to earlier periods.
📋 Yearly Climate Data Overview

🔥 hottest  ·  ❄️ coldest  ·  🌧️ wettest

Year Min Temp Avg Temp Max Temp Rainfall (mm) Avg Humidity Avg Wind

🏙️ Other Cities in Idaho

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❓ Frequently Asked Questions

What is the hottest month in Caldwell?
Based on 45 years of data (1981–2025), Jul is typically the hottest month in Caldwell, Idaho, with average high temperatures around 104.7°F.
What is the coldest month in Caldwell?
Jan is the coldest month in Caldwell, with average low temperatures around 10.7°F.
What is the rainiest month in Caldwell?
Dec receives the most rainfall with approximately 49 mm, while Jul is the driest with 8 mm.
What was the highest temperature ever recorded in Caldwell?
The highest recorded temperature was 110.9°F in Jun 2015. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in Caldwell?
The lowest recorded temperature was -13.2°F in Jan 2017.
How many years of data does this page cover?
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.
How much sunlight does Caldwell get?
Caldwell receives the most sunlight in Jul 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, agriculture, and understanding seasonal sunshine availability in Idaho.
Where does this weather data come from?
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.

📚 Data Source

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.

Parameters included:
  • Temperature (Min, Max)
  • Precipitation
  • Relative Humidity
  • Wind Speed
  • Solar Radiation
Data specifications:
  • Resolution: Monthly
  • Spatial: 0.5° × 0.625°
  • Source: MERRA-2
  • Coverage: 1981–2025
  • Years: 45