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Contents
- The climate of San Antonio
- The best time to visit San Antonio
- The worst time to visit San Antonio
- Spring weather in San Antonio
- Summer weather in San Antonio
- Autumn weather in San Antonio
- Winter weather in San Antonio
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average snowfall
- Average snowfall days
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Buildings in San Antonio, Texas, with a calm view of the bridges across the waterfront
The climate of San Antonio
San Antonio, located in Texas, USA, falls within the Köppen climate classification of Cfa, meaning it experiences a humid subtropical climate with no dry season. This geographical position lends itself to mild, moist winter months and hot, humid summers.
Throughout the year, San Antonio experiences a consistent range of temperatures. The lowest average monthly temperature of 44.2°F (6.8°C) typically settles in January, while the summer months of July and August peak with an average of 96.6°F (35.9°C). Humidity follows a similar pattern, with subsiding levels during cooler months and a surge during summer. Relative humidity rises from a January average of 64% to a May high of 73% before decreasing to a minimum of 59% in August.
Rainfall in San Antonio varies, with the highest averages occurring in May at 3.66" (93mm) and in September at 3.39" (86mm). In contrast, February and December both see relatively low rainfall with an average of only about 1 inch. The city enjoys over 10 hours of daylight throughout the year, with peak sunlight occurring in June (14 hours). Regarding wind, speeds range from a gentle 6.5mph (10.5km/h) in September to a brisk 9mph (14.5km/h) in May.
Throughout the year, San Antonio experiences a consistent range of temperatures. The lowest average monthly temperature of 44.2°F (6.8°C) typically settles in January, while the summer months of July and August peak with an average of 96.6°F (35.9°C). Humidity follows a similar pattern, with subsiding levels during cooler months and a surge during summer. Relative humidity rises from a January average of 64% to a May high of 73% before decreasing to a minimum of 59% in August.
Rainfall in San Antonio varies, with the highest averages occurring in May at 3.66" (93mm) and in September at 3.39" (86mm). In contrast, February and December both see relatively low rainfall with an average of only about 1 inch. The city enjoys over 10 hours of daylight throughout the year, with peak sunlight occurring in June (14 hours). Regarding wind, speeds range from a gentle 6.5mph (10.5km/h) in September to a brisk 9mph (14.5km/h) in May.
The best time to visit San Antonio
With warm temperatures, moderate humidity, and abundant sunshine, the optimal period for visiting San Antonio tends to fall in the spring, particularly between April and June. Daylight extends to approximately 13 hours in this period, coupled with up to 8.4 hours of sunshine. Despite an increased chance of rainfall, with averages from 1.85 to 2.09" (53mm), the weather remains pleasant. Average temperatures run from 72.7°F (22.6°C) to 85.6°F (29.8°C), making the city an appealing destination for outdoor activities and sightseeing.
The worst time to visit San Antonio
Visiting San Antonio could be less pleasurable between July and August. With temperatures soaring to an average high of 96.6°F (35.9°C) and humidity levels reaching up to 59%, the weather can feel oppressively hot and humid. These months also see the most prolonged daylight hours, extending beyond 13 hours, and thus have the potential for extreme warmth.
Spring weather in San Antonio
During the spring months of March, April, and May, San Antonio experiences rising temperatures, starting from an average low of 54.3°F (12.4°C) to a high of 85.6°F (29.8°C). Humidity also increases throughout spring, reaching 73% come May. Rainfall peaks in May with a monthly average of 3.66" (93mm), making it the wettest month of the year. Despite the rain, spring ushers in longer days with 12 to 13.6 hours of daylight, making it a delightful time for outdoor exploration.
Summer weather in San Antonio
Summers in San Antonio are marked by high temperatures, reaching an average of 92.1°F (33.4°C) in June and rising even further to 96.6°F (35.9°C) in August. Humidity drops slightly but remains relatively high, falling to 59%. Despite the rainfall being marginally lower (compared to spring), sudden summer showers are not uncommon and contribute towards 2.09" (53mm) in June and 1.5" (38mm) in August. Sunshine during the summer is also abundant, providing a pleasant balance to the heat.
Autumn weather in San Antonio
San Antonio's autumn months - September, October, and November - bring a gradual dip in temperatures. Average highs decrease from 89.1°F (31.7°C) in September to 69.8°F (21°C) in November. Humidity steadies around 66%, while the average rainfall hits a second peak in September, with 3.39" (86mm). The days shorten to between 11.4 and 10.7 daylight hours but still allow plenty of opportunities for tourists to enjoy the city.
Winter weather in San Antonio
Winter in San Antonio is mild, with December's lowest temperature averaging 46.9°F (8.3°C) and February's highest averaging 65.8°F (18.8°C). This period experiences the least humidity, with rates falling to an average of 64%. Although rainfall is lower compared to other seasons, December and February receive similar amounts, averaging around 1 inch. The limited daylight hours, averaging around 10.5 hours per day, and decreased sunshine hours might discourage outdoor activities. Still, the light chill and infrequent snowfalls make it a scenic time to visit.
Weather in January
San Antonio, Texas, encounters cool New Year weather. Slight fluctuations in temperatures mark the start of the year. The city experiences the second-highest visibility in this month compared to the rest of the year with values peaking at 6 miles. Weather in January »
Weather in February
Transitioning from January to February brings a slight increase in temperature. This rise is apparent during the day and continues into the mild nights. San Antonio in February is characterized by gradual warming, an increase in the average hours of daylight, and a relatively low UV index. Weather in February »
Weather in March
March brings a noticeable transition from the cool, short days of winter to the longer, warmer days of spring in San Antonio. The city starts to receive a larger amount of sunshine during the day, and the average hours of sunlight extend from 11.2 to 12 hours. Weather in March »
Weather in April
April experiences more dynamic and occasionally unpredictable weather conditions. Following March, San Antonio becomes warmer and experiences a more humid atmosphere. The rise in temperature goes hand in hand with an increase in the number of rainfall days, spiking from 14.1 days in March to 14.7 days in April. Weather in April »
Weather in May
In May, San Antonio turns noticeably warmer, giving the residents a feel of the upcoming summer heat. Observing the daylight hours extending to 13.6 hours indicates the fast approach of the summer solstice toward the end of June. Yet, despite the increasing temperature, May experiences substantial rainfall, reaching its peak at 3.66in. Weather in May »
Weather in June
June offers the first taste of summer in San Antonio. From May to June, daylight hours extend further, reaching their highest value at 14 hours. However, despite the hot days, rainfall lessens to 2.09in in June compared to May. Characterized by more sunshine and fewer clouds, San Antonio indeed starts reflecting the summer season. Weather in June »
Weather in July
Embracing the heart of summer, San Antonio's July weather becomes extremely hot. With recorded average temperature highs soaring to 95.5°F (35.3°C), July is typically the hottest month in the city. In contrast to the intense heat, the number of rain days are decreased to 10.4 days. Weather in July »
Weather in August
Heading from July to August, San Antonio experiences even warmer weather conditions. However, there is a less noticeable increase in temperature as compared to previous months. Meanwhile, the atmosphere gets drier, and cloud percentage drops further to 23%. Weather in August »
Weather in September
With September, San Antonio transitions from the intense summer heat to relatively cooler days. However, this month sees a significant increase in average rainfall from 1.5in in August to 3.39in in September. Despite the onset of autumn, the city remains warm and attracts visitors seeking late summer vacations. Weather in September »
Weather in October
October offers a significant transition from the hot, dry climate of September. The cooler evenings provide a much-needed respite from the heat, indicating the onset of autumn properly. San Antonio during October experiences a marked decrease in average daylight hours from 12.3 hours to 11.4 hours. Weather in October »
Weather in November
November brings a significant change in San Antonio's weather. It transitions from the moderate fall climate to the cooler conditions that signal the start of winter. The decrease in temperature is complemented with reduced daylight hours, dropping to 10.7 hours. Weather in November »
Weather in December
December is the coolest month in San Antonio, Texas. The city transitions into wintry conditions, with shorter days and longer nights, in line with the winter solstice towards the end of the month. It's the only month to witness any snowfall, with a minimal average of 0.04in. Weather in December »
Updated: Jul 14, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the coldest time of year in San Antonio?
January, marked by an average high-temperature of 61.7°F (16.5°C) and a low-temperature of 44.2°F (6.8°C), is the coldest month in San Antonio.
How many days does it rain?
Throughout the year, there are 144.5 rainfall days, and 22.6" (574mm) of precipitation is accumulated.
When does it snow?
Months with snowfall are January, February and December.
When does it snow the most?
The months with the most snowfall are January and February, with an average 0.08" (2mm) of accumulated snow.
How much does it snow?
Throughout the year, there are 0.7 snowfall days, and 0.2" (5mm) of snow is accumulated.
What is the driest month?
The month with the least rainfall is February, when the rain falls for 10.7 days and typically collects 0.98" (25mm) of precipitation.
When it does not snow in San Antonio?
March through November are months without snowfall.
When is Daylight Saving Time (DST)?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
What is the most humid month?
May is the most humid month, with an average relative humidity of 73%.
What is the wettest month?
The month with the most rainfall is May, when the rain falls for 16.4 days and typically aggregates up to 3.66" (93mm) of precipitation.
When are the longest days?
With an average of 14h and 0min of daylight, June has the longest days of the year.
What is the month with the highest UV index?
June through August, with an average maximum UV index of 7, are months with the highest UV index.
What month has the most sunshine?
With an average of 10.3h of sunshine, July has the most sunshine of the year in San Antonio.
What time of the year is the hottest?
The month of August sees the average highest temperatures, reaching 96.6°F (35.9°C) at the peak and 75.7°F (24.3°C) at the low.
What is the least humid month in San Antonio?
August is the least humid month, with an average relative humidity of 59%.
What is the month with the shortest days?
With an average of 10h and 18min of daylight, December has the shortest days of the year.
What is the month with the least sunshine?
With an average of 5.3h of sunshine, December has the least sunshine of the year.
What is the month with the lowest UV index?
With an average maximum UV index of 3, December is the month with the lowest UV index.
Average temperature
San Antonio, TX
The warmest month (with the highest average high temperature) is August (96.6°F).
The month with the lowest average high temperature is January (61.7°F).
The month with the highest average low temperature is August (75.7°F).
The coldest month (with the lowest average low temperature) is January (44.2°F).
Average pressure
San Antonio, TX
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.07"Hg - Average pressure in March:
30.01"Hg - Average pressure in April:
29.91"Hg - Average pressure in May:
29.9"Hg - Average pressure in June:
29.89"Hg
- Average pressure in July:
29.94"Hg - Average pressure in August:
29.91"Hg - Average pressure in September:
29.94"Hg - Average pressure in October:
29.99"Hg - Average pressure in November:
30.1"Hg - Average pressure in December:
30.11"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed
San Antonio, TX
- Average wind speed in January:
8mph - Average wind speed in February:
8.6mph - Average wind speed in March:
8.8mph - Average wind speed in April:
8.9mph - Average wind speed in May:
9mph - Average wind speed in June:
8mph
- Average wind speed in July:
7.6mph - Average wind speed in August:
7.1mph - Average wind speed in September:
6.5mph - Average wind speed in October:
7.5mph - Average wind speed in November:
7.7mph - Average wind speed in December:
7.7mph
The windiest month (with the highest average wind speed) is May (9mph).
The calmest month (with the lowest average wind speed) is September (6.5mph).
Average humidity
San Antonio, TX
The month with the highest relative humidity is May (73%).
The month with the lowest relative humidity is August (59%).
Average rainfall
San Antonio, TX
- Average rainfall in January:
1.14" - Average rainfall in February:
0.98" - Average rainfall in March:
1.54" - Average rainfall in April:
1.85" - Average rainfall in May:
3.66" - Average rainfall in June:
2.09"
The wettest month (with the highest rainfall) is May (3.66").
The driest month (with the least rainfall) is February (0.98").
Average rainfall days
San Antonio, TX
- Average rainfall days in January:
9.1 days - Average rainfall days in February:
10.7 days - Average rainfall days in March:
14.1 days - Average rainfall days in April:
14.7 days - Average rainfall days in May:
16.4 days - Average rainfall days in June:
13.1 days
- Average rainfall days in July:
10.4 days - Average rainfall days in August:
9.8 days - Average rainfall days in September:
17 days - Average rainfall days in October:
9.8 days - Average rainfall days in November:
9.5 days - Average rainfall days in December:
9.9 days
The month with the highest number of rainy days is September (17 days).
The month with the least rainy days is January (9.1 days).
Average snowfall
San Antonio, TX
The months with the highest snowfall are January and February (0.08").
The months with the least snowfall are March, April, May, June, July, August, September, October and November (0").
Average snowfall days
San Antonio, TX
- Average snowfall days in January:
0.3 days - Average snowfall days in February:
0.3 days - Average snowfall days in March:
0 days - Average snowfall days in April:
0 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0 days - Average snowfall days in November:
0 days - Average snowfall days in December:
0.1 days
The months with the highest number of snowfall days are January and February (0.3 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October and November (0 days).
Average daylight / Average sunshine
San Antonio, TX
- Average daylight in January:
10h and 3min - Average daylight in February:
11h and 1min - Average daylight in March:
12h and 0min - Average daylight in April:
12h and 5min - Average daylight in May:
13h and 4min - Average daylight in June:
14h and 0min
- Average daylight in July:
13h and 5min - Average daylight in August:
13h and 1min - Average daylight in September:
12h and 2min - Average daylight in October:
11h and 2min - Average daylight in November:
10h and 4min - Average daylight in December:
10h and 2min
The month with the longest days is June (Average daylight: 14h and 0min).
The month with the shortest days is December (Average daylight: 10h and 18min).
- Average sunshine in January:
6h and 2min - Average sunshine in February:
6h and 4min - Average sunshine in March:
6h and 3min - Average sunshine in April:
7h and 2min - Average sunshine in May:
8h and 0min - Average sunshine in June:
9h and 2min
- Average sunshine in July:
10h and 2min - Average sunshine in August:
9h and 5min - Average sunshine in September:
8h and 2min - Average sunshine in October:
7h and 2min - Average sunshine in November:
5h and 2min - Average sunshine in December:
5h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).
Average sunshine days
San Antonio, TX
- Average sunshine days in January:
20.3 days - Average sunshine days in February:
15.3 days - Average sunshine days in March:
13.9 days - Average sunshine days in April:
12.9 days - Average sunshine days in May:
11.8 days - Average sunshine days in June:
14.2 days
- Average sunshine days in July:
18.1 days - Average sunshine days in August:
19.8 days - Average sunshine days in September:
11.8 days - Average sunshine days in October:
17.8 days - Average sunshine days in November:
18.3 days - Average sunshine days in December:
19 days
The month with the most sunshine days is January (20.3 days).
The months with the least sunshine days are May and September (11.8 days).
Average UV index
San Antonio, TX
The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover
San Antonio, TX
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 23).
Average visibility
San Antonio, TX
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
San Antonio, Texas, USA
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