San Antonio, Texas Weather History

Texas, United States  •  45 yrs data 📍 29.4711°N, 98.5152°W
°F / °C
☀️

Quick Climate Facts

(1981 – 2025)
Hottest Month
🔥
Aug
Avg 87.1°F
Min 70.2°F
Max 103.9°F
Coldest Month
❄️
Jan
Avg 51.6°F
Min 26°F
Max 77.3°F
Wettest Month
🌧️
May
104 mm
Driest Month
🏜️
Feb
44 mm
Most Humid
💧
Dec
71%
Least Humid
🌬️
Aug
60%
Highest Ever
🌡️
112.6°F
Sep 2000
Lowest Ever
🧊
9°F
Dec 1989
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 San Antonio Across Seasons

❄️ Winter in San Antonio

January is San Antonio's coldest month, with average lows reaching 26.1°F.
🌡️ December to February (avg)  ·  27°F79.3°F

🧥 Expect frosty nights and below-freezing temperatures during this Cold Winter period.

☀️ Summer in San Antonio

Summer temperatures in San Antonio peak in August, climbing to 104°F.
🌡️ June to August (avg)  ·  68.2°F102.7°F

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

🌧️ Rainy Season in San Antonio

San Antonio sees its highest rainfall in May, receiving approximately 104 mm of precipitation.
🌧️ May to October (avg)  ·  up to 104 mm

☔ Moderate Rainfall expected — carry rain gear and plan outdoor activities around these months.

📅 Monthly Averages

🌡️ Temperature Patterns

Monthly averages · 1981–2025 climate normals · °F

🌡️ San Antonio Monthly Temperature Guide

Aug is the hottest month in San Antonio, with average highs reaching 103.9°F, while Jan is the coldest with lows dropping to 26°F.

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

These seasonal patterns make summer pleasant for travel, while winters can bring frost and occasional snowfall.

🌧️ Rainfall Distribution

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

💨 Humidity & Wind Speed

Monthly averages · 1981–2025

💧 Rainfall & Humidity in San Antonio

San Antonio receives its highest rainfall in May, while humidity peaks during winter months.
🌧️ Wettest: May — 104 mm ☀️ Driest: Feb — 44 mm

💧 Humidity peaks at 71% in Dec · annual avg 67%

🌍 Climate Summary

Avg Annual Temp:69.1°F
Avg Annual Rainfall:781 mm
Avg Humidity:67%
Data Period:1981 – 2025

San Antonio Climate Overview

San Antonio has a warm subtropical climate with warm summers and cold winters.

Temperatures peak in Aug and drop to their lowest in Jan, while rainfall is highest during spring and early summer months.

Humidity remains moderate throughout the year, especially during winter months, creating cold and damp conditions.

📈 Yearly Trends

The warmest year in San Antonio's recorded history was 2024 (avg: 73.2°F), while the coldest year was 1992 (avg: 65.3°F), based on annual average temperatures.

📊 Key Climate Trends

🌡️ Annual Temperature Trend

View Range:

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

San Antonio's temperatures shows a slight warming trend over the past decade. The highest recorded temperature reached 112.6°F in Sep 2000, while the lowest dropped to 9°F in Dec 1989.

🌧️ Annual Precipitation

View Range:

Total annual precipitation · Last 10 years · mm/year

Annual rainfall in San Antonio shows noticeable variation. Rainfall has decreased 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 Texas

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❓ Frequently Asked Questions

What is the hottest month in San Antonio?
Based on 45 years of data (1981–2025), Aug is typically the hottest month in San Antonio, Texas, with average high temperatures around 103.9°F.
What is the coldest month in San Antonio?
Jan is the coldest month in San Antonio, with average low temperatures around 26°F.
What is the rainiest month in San Antonio?
May receives the most rainfall with approximately 104 mm, while Feb is the driest with 44 mm.
What was the highest temperature ever recorded in San Antonio?
The highest recorded temperature was 112.6°F in Sep 2000. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in San Antonio?
The lowest recorded temperature was 9°F in Dec 1989.
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 San Antonio get?
San Antonio receives the most sunlight in Jul with an average solar radiation of 6.77 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability in Texas.
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