Average Weather in San Antonio Mexico
In San Antonio, the summers are long, hot, and muggy; the winters are short, cool, and dry; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 49°F to 96°F and is rarely below 39°F or above 101°F.
Based on the beach/pool score, the best time of year to visit San Antonio for hot-weather activities is from early May to mid July.
The hot season lasts for 4.1 months, from May 8 to September 11, with an average daily high temperature above 90°F. The hottest day of the year is July 29, with an average high of 96°F and low of 74°F.
The cool season lasts for 2.4 months, from November 24 to February 8, with an average daily high temperature below 75°F. The coldest day of the year is January 5, with an average low of 49°F and high of 70°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature
In San Antonio, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.
The clearer part of the year in San Antonio begins around April 10 and lasts for 2.5 months, ending around June 27. On June 2, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 77% of the time, and overcast or mostly cloudy 23% of the time.
The cloudier part of the year begins around June 27 and lasts for 9.5 months, ending around April 10. On September 6, the cloudiest day of the year, the sky is overcast or mostly cloudy 52% of the time, and clear, mostly clear, or partly cloudy 48% of the time.
Cloud Cover Categories
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in San Antonio varies significantly throughout the year.
The wetter season lasts 4.9 months, from May 11 to October 9, with a greater than 22% chance of a given day being a wet day. The chance of a wet day peaks at 40% on September 9.
The drier season lasts 7.1 months, from October 9 to May 11. The smallest chance of a wet day is 5% on December 10.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 40% on September 9.
Daily Chance of Precipitation
To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. San Antonio experiences significant seasonal variation in monthly rainfall.
The rainy period of the year lasts for 11 months, from December 29 to November 29, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around September 13, with an average total accumulation of 4.4 inches.
The rainless period of the year lasts for 1.0 months, from November 29 to December 29. The least rain falls around December 17, with an average total accumulation of 0.4 inches.
Average Monthly Rainfall
The length of the day in San Antonio varies over the course of the year. In 2018, the shortest day is December 21, with 10 hours, 32 minutes of daylight; the longest day is June 21, with 13 hours, 44 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 6:32 AM on March 31, and the latest sunrise is 1 hour, 13 minutes later at 7:45 AM on October 27. The earliest sunset is at 5:48 PM on November 30, and the latest sunset is 2 hours, 47 minutes later at 8:35 PM on July 2.
Daylight saving time (DST) is observed in San Antonio during 2018, starting in the spring on April 1, lasting 6.8 months, and ending in the fall on October 28.
Sunrise & Sunset with Twilight and Daylight Saving Time
San Antonio experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 6.7 months, from April 14 to November 6, during which time the comfort level is muggy, oppressive, or miserable at least 21% of the time. The muggiest day of the year is September 4, with muggy conditions 84% of the time.
The least muggy day of the year is January 30, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed in San Antonio experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 5.6 months, from March 10 to August 30, with average wind speeds of more than 8.1 miles per hour. The windiest day of the year is July 4, with an average hourly wind speed of 9.8 miles per hour.
The calmer time of year lasts for 6.4 months, from August 30 to March 10. The calmest day of the year is December 6, with an average hourly wind speed of 6.3 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in San Antonio is from the east throughout the year.
Best Time of Year to Visit
To characterize how pleasant the weather is in San Antonio throughout the year, we compute two travel scores.
The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best times of year to visit San Antonio for general outdoor tourist activities are from early March to late May and from early October to late November, with a peak score in the last week of October.
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit San Antonio for hot-weather activities is from early May to mid July, with a peak score in the first week of June.
For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.
Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.
Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.
Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.
Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.
Temperatures in San Antonio are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.
Time Spent in Various Temperature Bands and the Growing Season
Growing Degree Days
The average daily incident shortwave solar energy experiences significant seasonal variation over the course of the year.
The brighter period of the year lasts for 4.2 months, from April 10 to August 16, with an average daily incident shortwave energy per square meter above 6.7 kWh. The brightest day of the year is June 13, with an average of 7.4 kWh.
The darker period of the year lasts for 2.6 months, from November 12 to February 1, with an average daily incident shortwave energy per square meter below 4.6 kWh. The darkest day of the year is December 19, with an average of 3.9 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of San Antonio are 25.639 deg latitude, -100.058 deg longitude, and 1,234 ft elevation.
The topography within 2 miles of San Antonio contains only modest variations in elevation, with a maximum elevation change of 197 feet and an average elevation above sea level of 1,228 feet. Within 10 miles contains only modest variations in elevation (3,196 feet). Within 50 miles contains large variations in elevation (11,742 feet).
The area within 2 miles of San Antonio is covered by cropland (68%) and shrubs (28%), within 10 miles by cropland (58%) and shrubs (26%), and within 50 miles by shrubs (43%) and cropland (29%).
This report illustrates the typical weather in San Antonio, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There is only a single weather station, General Mariano Escobedo International Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of San Antonio.
At a distance of 16 kilometers from San Antonio, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.
The station records are corrected for the elevation difference between the station and San Antonio according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
Please note that the station records themselves may additionally have been back-filled using other nearby stations or the MERRA-2 reanalysis.
Time zones for aiports and weather stations are provided by AskGeo.com .