May weather forecastSan Antonio, TX
May
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. An increase in humidity radiates an elevated sense of warmth. The generous rainfall and increased sunshine promotes faster-growing flora, adding vibrant colors to the cityscape.Temperature
May's arrival coincides with a marginal rise in the average high-temperature, moving from April's 79.7°F (26.5°C) to a still warm 85.6°F (29.8°C). Throughout May nights, San Antonio experiences a consistent temperature average of 67.3°F (19.6°C).Heat index
For May, the heat index is computed to be a sweltering 95°F (35°C). Exercise enhanced safety steps, heat cramps and heat exhaustion are probable. Heatstroke could be a result of sustained activity.The heat index's values are generally associated with conditions in shade and light breezes. Under direct sunshine, the heat index values might be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', takes into account both air temperature and humidity to illustrate what people actually feel. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. Sunshine, when direct, has the potential to intensify weather effects, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Young individuals usually face greater risks than adults as their sweat production is less. Also, their larger skin surface relative to their small bodies and the high heat generation due to their activity contributes to their vulnerability.
The body's inherent cooling system operates through perspiration, wherein evaporating sweat offsets excessive heat. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. When heat gain surpasses the level the body can shed, body temperature begins to increase, and consequently, overheating and dehydration can occur, with varying severity.
Humidity
With an average relative humidity of 73%, May is the most humid month.Rainfall
May is the month with the most rainfall. Rain falls for 16.4 days and accumulates 3.66" (93mm) of precipitation.Snowfall
March through November are months without snowfall.Daylight
In San Antonio, the average length of the day in May is 13h and 38min.On the first day of the month, sunrise is at 6:51 am and sunset at 8:10 pm. On the last day of May, sunrise is at 6:34 am and sunset at 8:28 pm CDT.
Sunshine
In May, the average sunshine is 8h.UV index
The average daily maximum UV index in May is 6. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for the ordinary person.Note: In May, a daily UV index of 6 turns into the following recommendations:
Embrace precautions and observe sun safety norms. Evasion of sunburn is a necessity. Stay out of direct sunlight and seek shade between 10 a.m. and 4 p.m., when UV radiation is strongest, but remember that shade devices may not offer full sun protection. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
San Antonio, TX
- Average high temperature in May: 85.6°F
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).
- Average low temperature in May: 67.3°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 in May
San Antonio, TX
- Average pressure in May: 29.9"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 in May
San Antonio, TX
- Average wind speed in May: 9mph
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 in May
San Antonio, TX
- Average humidity in May: 73%
The month with the highest relative humidity is May (73%).
The month with the lowest relative humidity is August (59%).
Average rainfall in May
San Antonio, TX
- Average rainfall in May: 3.66"
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 in May
San Antonio, TX
- Average rainfall days in May: 16.4 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 in May
San Antonio, TX
- Average snowfall in May: 0"
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 in May
San Antonio, TX
- Average snowfall days in May: 0 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 in May /
Average sunshine in May
San Antonio, TX
- Average daylight in May: 13h and 36min
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 May: 8h and 0min
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 in May
San Antonio, TX
- Average sunshine days in May: 11.8 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 in May
San Antonio, TX
- Average UV index in May: 6
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 in May
San Antonio, TX
- Average cloud cover in May: 46
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 in May
San Antonio, TX
- Average visibility in May: 6mi
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).
