April is close to San Antonio's year-round average, with average highs near 28.6°C and lows around 14.2°C (mean 21.4°C). It is about average for rainfall, averaging 62 mm of rainfall and 65% relative humidity across the period.
April is close to San Antonio's year-round average. Across 45 years of records, the warmest April in San Antonio was 2011 — when the month averaged 25.3°C — while the coldest was 1997 at 17.5°C. Typical April days reach 28.6°C with nights near 14.2°C. The long-term trend is warming, about 0.3°C per decade.
April is about average for rainfall in San Antonio, averaging 62 mm of rainfall. The wettest April on record was 2004 with 195 mm, while the driest was 2011 at 1 mm.
Relative humidity in San Antonio during April averages 65%. The most humid April was 1992 at 82%, and the least humid was 1984 at 39%.
April receives about 5.4 kWh/m²/day of solar energy in San Antonio. The sunniest April was 1998 at 6.5 kWh/m²/day, and the cloudiest were 1990 and 2004 at 4.4.
Average wind speed in San Antonio during April is 3.1 m/s. The windiest April was 2011 at 3.9 m/s, while the calmest was 1992 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.3°C | 20.4°C | 21.5°C | 21.6°C | 22.8°C | +1.5°C |
| Avg High | 29.0°C | 27.6°C | 28.4°C | 28.6°C | 30.0°C | +1°C |
| Avg Low | 13.7°C | 13.2°C | 14.7°C | 14.5°C | 15.6°C | +1.9°C |
| Avg Rain | 42 mm | 77 mm | 64 mm | 61 mm | 62 mm | +20 mm |
April temperatures in San Antonio have risen by about 1.8°C between 1981–1985 and 2021–2025.
April has ranged from a record low of 0.5°C (1987) to a record high of 40.7°C (1984).
Rainfall in April is about average for rainfall, averaging 62 mm, with a wettest year of 195 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.2°C per decade while lows rose 0.4°C per decade, narrowing the gap between day and night.
One of the best times to visit San Antonio
April is one of the best times to visit San Antonio. Expect days averaging 28.6°C and nights around 14.2°C (mean 21.4°C) — close to San Antonio's yearly average — with moderate rainfall (62 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 31.3°C | 24.1°C | 16.8°C | 35.8°C | 4.3°C | 44 mm | 63% | 3.3 m/s | 5.6 |
| 2024 | 30.3°C | 23.4°C | 16.5°C | 34.4°C | 8.8°C | 55 mm | 66% | 3.2 m/s | 5 |
| 2023 | 28.0°C | 21.3°C | 14.6°C | 35.9°C | 9.8°C | 107 mm | 66% | 3.1 m/s | 4.9 |
| 2022 | 32.1°C | 24.5°C | 16.8°C | 37.1°C | 8.2°C | 31 mm | 58% | 3.6 m/s | 5.2 |
| 2021 | 29.5°C | 22.1°C | 14.6°C | 38.1°C | 7.6°C | 70 mm | 58% | 3.4 m/s | 4.9 |
| 2020 | 28.5°C | 21.3°C | 14.0°C | 36.9°C | 5.9°C | 65 mm | 67% | 3 m/s | 5.3 |
| 2019 | 28.5°C | 21.1°C | 13.7°C | 35.8°C | 4.5°C | 92 mm | 66% | 3.2 m/s | 5.8 |
| 2018 | 28.0°C | 20.3°C | 12.7°C | 33.4°C | 4.0°C | 21 mm | 61% | 3.1 m/s | 5.7 |
| 2017 | 28.6°C | 21.8°C | 15.1°C | 34.8°C | 9.2°C | 61 mm | 67% | 3.2 m/s | 5.7 |
| 2016 | 27.8°C | 21.3°C | 14.9°C | 33.3°C | 6.3°C | 113 mm | 70% | 2.7 m/s | 5.3 |
| 2015 | 26.1°C | 21.0°C | 15.9°C | 31.7°C | 8.4°C | 145 mm | 78% | 2.6 m/s | 4.5 |
| 2014 | 28.9°C | 21.4°C | 14.0°C | 37.5°C | 3.4°C | 19 mm | 57% | 3.2 m/s | 5.6 |
| 2013 | 27.7°C | 20.3°C | 12.8°C | 34.5°C | 4.5°C | 78 mm | 66% | 3.3 m/s | 5 |
| 2012 | 30.6°C | 23.1°C | 15.6°C | 38.0°C | 10.5°C | 6 mm | 64% | 3.2 m/s | 5.9 |
| 2011 🔥 | 33.7°C | 25.3°C | 16.9°C | 38.5°C | 7.5°C | 1 mm | 50% | 3.9 m/s | 6.3 |
| 2010 | 26.2°C | 19.9°C | 13.6°C | 31.7°C | 6.2°C | 71 mm | 73% | 3.3 m/s | 4.9 |
| 2009 | 27.7°C | 20.8°C | 13.8°C | 36.1°C | 4.9°C | 81 mm | 58% | 3.8 m/s | 5.5 |
| 2008 | 29.7°C | 22.0°C | 14.2°C | 34.0°C | 7.2°C | 44 mm | 59% | 3.4 m/s | 5.8 |
| 2007 | 23.9°C | 18.0°C | 12.2°C | 29.6°C | 1.1°C | 77 mm | 76% | 3 m/s | 4.9 |
| 2006 | 32.2°C | 24.6°C | 17.0°C | 38.8°C | 10.5°C | 36 mm | 61% | 3.2 m/s | 5.8 |
| 2005 | 27.8°C | 20.5°C | 13.2°C | 36.2°C | 5.3°C | 12 mm | 62% | 3.1 m/s | 5.9 |
| 2004 🌧️ | 24.8°C | 19.4°C | 14.1°C | 29.2°C | 5.3°C | 195 mm | 80% | 3 m/s | 4.4 |
| 2003 | 28.8°C | 21.5°C | 14.3°C | 34.8°C | 3.6°C | 4 mm | 65% | 3.1 m/s | 5.4 |
| 2002 | 30.7°C | 24.1°C | 17.5°C | 39.2°C | 10.6°C | 68 mm | 69% | 3.3 m/s | 5.3 |
| 2001 | 28.3°C | 22.1°C | 15.9°C | 32.8°C | 8.7°C | 57 mm | 73% | 3.4 m/s | 4.6 |
| 2000 | 29.6°C | 22.0°C | 14.4°C | 36.7°C | 5.2°C | 70 mm | 62% | 3.2 m/s | 5.5 |
| 1999 | 30.4°C | 23.0°C | 15.6°C | 37.5°C | 7.2°C | 31 mm | 63% | 3.2 m/s | 5.4 |
| 1998 | 28.5°C | 20.2°C | 11.9°C | 34.6°C | 6.0°C | 13 mm | 57% | 3 m/s | 6.5 |
| 1997 ❄️ | 23.9°C | 17.5°C | 11.0°C | 32.5°C | 1.7°C | 141 mm | 75% | 3 m/s | 5.1 |
| 1996 | 30.3°C | 21.3°C | 12.2°C | 39.0°C | 2.9°C | 50 mm | 50% | 3.5 m/s | 6.2 |
| 1995 | 28.9°C | 20.8°C | 12.7°C | 35.8°C | 6.6°C | 60 mm | 65% | 3.1 m/s | 5.8 |
| 1994 | 27.8°C | 20.9°C | 14.0°C | 36.3°C | 3.8°C | 88 mm | 69% | 3.2 m/s | 5.5 |
| 1993 | 27.1°C | 19.5°C | 11.9°C | 33.7°C | 5.3°C | 65 mm | 66% | 3.2 m/s | 5.4 |
| 1992 | 24.4°C | 18.6°C | 12.8°C | 28.0°C | 4.8°C | 110 mm | 82% | 2.4 m/s | 5.3 |
| 1991 | 27.9°C | 21.4°C | 14.9°C | 34.0°C | 6.0°C | 120 mm | 73% | 2.6 m/s | 5.1 |
| 1990 | 26.9°C | 20.7°C | 14.5°C | 33.9°C | 5.1°C | 87 mm | 74% | 3.4 m/s | 4.4 |
| 1989 | 29.0°C | 21.4°C | 13.7°C | 37.0°C | 4.2°C | 65 mm | 65% | 2.9 m/s | 5.5 |
| 1988 | 29.4°C | 21.1°C | 12.9°C | 36.1°C | 4.3°C | 37 mm | 52% | 2.8 m/s | 5.9 |
| 1987 | 27.0°C | 18.9°C | 10.8°C | 35.4°C | 0.5°C | 17 mm | 60% | 2.5 m/s | 5.9 |
| 1986 | 31.5°C | 23.9°C | 16.4°C | 36.1°C | 10.9°C | 32 mm | 60% | 3.3 m/s | 4.8 |
| 1985 | 27.3°C | 20.8°C | 14.3°C | 34.5°C | 5.6°C | 90 mm | 71% | 2.8 m/s | 5.2 |
| 1984 | 31.2°C | 22.6°C | 14.0°C | 40.7°C | 7.5°C | 11 mm | 39% | 3.3 m/s | 6.3 |
| 1983 | 27.8°C | 19.3°C | 10.9°C | 37.3°C | 3.4°C | 4 mm | 57% | 3.4 m/s | — |
| 1982 | 29.0°C | 21.4°C | 13.8°C | 37.6°C | 5.9°C | 54 mm | 61% | 3.2 m/s | — |
| 1981 | 28.5°C | 22.6°C | 16.8°C | 33.1°C | 8.8°C | 70 mm | 71% | 3.1 m/s | — |
Actual recorded April data for each year, 1981–2025 — sourced from NASA POWER.
The average high in April is around 28.6°C with lows near 14.2°C (mean 21.4°C), based on 45 years of NASA POWER data.
April averages 62 mm of rainfall in San Antonio, about average for rainfall. The wettest on record was 195 mm in 2004.
The hottest April reached 40.7°C in 1984. The coldest dipped to 0.5°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average April temperatures have risen by about 1.8°C. Daytime highs moved from 28.8°C to 30.2°C and overnight lows from 14°C to 15.9°C over the same span.
April is close to San Antonio's year-round average and about average for rainfall, so plan for around 28.6°C daytime highs and 14.2°C at night.
Not quite — April is the 6th coolest month in San Antonio, averaging 21.4°C.
For April in San Antonio, pack light layers you can adjust through the day, with typical highs of 28.6°C and lows of 14.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in April averages 65% — moderately humid.
Average wind speed in April is 3.1 m/s. The windiest April on record averaged 3.9 m/s (2011).
The wettest April on record was 2004 with 195 mm. On average, April sees 62 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in San Antonio behaves each April, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for April specifically, along with year-by-year records and how the month has changed over the decades.
