April Weather in San Marcos, United States

Last updated: February 24, 2025

April in San Marcos, United States showcases a striking blend of temperatures and weather patterns. With a maximum reaching 35°C (94°F) and a mild average of 20°C (69°F), the month provides a warm respite, although temperatures can dip as low as 3°C (38°F). Rainfall is a notable feature, with a total precipitation amount of 89 mm (3.5 in) spread across 9 days, contributing to the region's 76% humidity. This combination of warmth and moisture creates a unique spring climate, making April a vibrant time for both residents and visitors.

April Temperature in San Marcos

In April, San Marcos begins to shake off the winter chill, with temperatures rising noticeably across the board. The minimum temperature nudges up to 3°C (38°F), providing a stark contrast to the deeper winter months, while the average climbs to a pleasant 20°C (69°F). This month marks a pivotal transition, as the maximum temperature can reach an inviting 35°C (94°F), hinting at the sweltering summer that lies just ahead. Overall, April is characterized by a gradual warming trend, making it a delightful time for outdoor activities as the city basks in increasingly temperate conditions.

April Weather in San Marcos: Daily Temperature Highs, Lows, and Averages

The chart illustrates April temperature patterns in San Marcos, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec525363687681848579706055
Data source: Temperature data for San Marcos generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

April Precipitation in San Marcos

In April, San Marcos experiences a notable increase in precipitation, with 89 mm (3.5 in) of rain recorded over 9 days. This uptick reflects a consistent upward trend in rainfall from the earlier months, as January's 48 mm and February's 60 mm gradually transformed into March's 67 mm. The arrival of spring is marked by heightened moisture levels, paving the way for lush landscapes and vibrant blooms. As the region transitions into May, which sees even heavier rainfall at 149 mm (5.9 in), it’s clear that April serves as a pivotal month in San Marcos’ annual precipitation cycle, bridging the gap between the milder rains of early year and the more intense downpours of late spring.

April Precipitation Trends in San Marcos

The chart displays monthly precipitation patterns in San Marcos, with values for each month alongside April's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how April's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec4860678914910280111112944973
Data source: Precipitation data for April generated using information from the Copernicus Climate Change Service.
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April Humidity in San Marcos

In April, San Marcos experiences a humidity level of 76%, a slight dip from the 74% recorded in March. This trend marks a transition into the more humid months as the year progresses; humidity begins to rise again in May, reaching 81%. Overall, the spring months exhibit shifting humidity patterns, peaking in the winter with 79% in both January and February, before gradually declining into the summer heat of July, which sees a significant drop to 66%. Thus, April serves as a bridge between the cooler, more humid months and the warmer, drier summer, making it a unique point in the weather rhythm of San Marcos.

April Average Humidity in San Marcos

This chart illustrates the average monthly humidity levels in San Marcos, with April's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how April's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec79%79%74%76%81%76%66%58%65%74%81%86%
Data source: Humidity data for April generated using information from the Copernicus Climate Change Service.

April UV Index in San Marcos

As we step into April in San Marcos, the UV Index escalates to an extreme level of 11, marking a significant increase from the previous months. This trend continues from March's high of 9, and offers a stark reminder of the sun's intensity during spring. With a rapid burn time of just 10 minutes, residents and visitors are urged to take extra precautions under the relentless sun. The intense UV radiation in April is a precursor to the summer months, where this extreme exposure continues through to September. Staying informed about the UV Index is crucial for skin safety, particularly during these peak spring and summer months. For more detailed information on UV levels and safety recommendations, check out San Marcos UV Index.

Maximum UV Index Levels in San Marcos for April

The chart shows the monthly maximum UV Index (UVI) for San Marcos in April, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec589111112121211965
Data source: San Marcos April UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

April Sunshine in San Marcos

As April unfolds in San Marcos, the city basks in an impressive 260 hours of sunshine, marking a delightful increase from the previous months. This uplift not only reflects the gradual warming of the spring season but also sets the stage for even brighter months ahead. Notably, the sunny days tend to escalate dramatically as the year progresses, peaking in July with 348 hours. The trend showcases spring’s gradual transition into the summer months, making April a perfect time for outdoor activities and soaking up the sun. The consistent rise in sunshine from January's modest 170 hours highlights San Marcos as a favored destination for sun-seekers, eager to embrace the vibrant atmosphere that accompanies its luminous skies.

Monthly Sunshine Duration in San Marcos: April Highlighted

The April sunshine duration represents the total number of hours San Marcos experiences direct sunlight during the month of April, excluding cloudy or obstructed periods. This chart compares the sunshine duration of April with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec170h165h229h260h282h329h348h329h277h270h230h223h
Data source: San Marcos April Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Marcos During April

In San Marcos, the likelihood of sunny weather in April is relatively modest, with a 41% chance of sunshine. This represents a slight dip compared to the preceding months, particularly the brighter January, which boasts a 58% chance. As spring unfolds, the chances of sunshine continue to lessen through March and into April, hinting at a transitional phase before the summer heat sets in. Interestingly, the region experiences a notable uptick in sunny days as summer approaches, with May seeing a 29% likelihood and July dropping to 31%, underscoring the unpredictable nature of early spring weather. Thus, while April may not promise an abundance of sunlight, it still holds its own amid the fluctuating weather patterns characteristic of San Marcos.

Percentage of Sunny Days in April in San Marcos

The chart illustrates the percentage of sunny days in San Marcos throughout the year, with April highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often San Marcos experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec58%44%50%41%29%42%31%37%59%52%57%37%
Data source: San Marcos April chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Marcos in April

As April unfolds in San Marcos, residents enjoy a delightful 12 hours of daylight, a continuation of the longer days that began in March. This marks a significant increase from the 10 hours of daylight seen in January, setting the stage for a vibrant spring. With daylight gradually extending through the month, April mirrors the transitional phase between the brisk chill of winter and the sun-drenched days of summer. Following this month, daylight will further increase to 13 hours in May, highlighting a trend of gradually lengthening days that peak in June at 14 hours—ideal for outdoor activities and soaking up the sunshine. As the year progresses, daylight begins to shorten again, but April stands out as a pivotal time of growth and brightness in San Marcos.

Average Daylight Hours in San Marcos for April

The chart illustrates the variation in daylight duration in San Marcos throughout the year, with April highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 26m11h 7m12h12h 54m13h 40m14h 2m13h 50m13h 9m12h 17m11h 23m10h 37m10h 13m
Data source: San Marcos daylight hours, calculated by summing the hours between sunrise and sunset for each day.

April Winds in San Marcos

In April, San Marcos experiences a gentle yet invigorating breeze, with an average wind speed of 3.9 m/s (9 mph), mirroring the mild conditions of February and March. This month stands out as the last peak before a gradual decline in wind speeds leading into the summer months. Notably, April maintains a consistent velocity, suggesting a transitional phase as warmer days approach. The overall trend reveals a seasonal ebb and flow; following this lively April wind, the speeds dip slightly in May, eventually reaching their lowest levels in the summer heat. As residents and visitors enjoy the beauty of spring, the refreshing April winds serve as a reminder of the invigorating change inherent in this vibrant time of year.

Average April Wind Speed in San Marcos

The chart displays monthly wind speed patterns in San Marcos, with values for each month shown alongside April's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how April's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.43.94.13.9 m/s3.62.92.52.72.53.13.23.4
Data source: San Marcos April wind data, generated using information from the Copernicus Climate Change Service.

How April Weather in San Marcos Compares to Other Months

The weather in San Marcos changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of April's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in San Marcos and find detailed weather information for every month.

April and January in San Marcos exhibit stark differences in weather patterns. April typically features a much warmer climate, with average temperatures around 20°C (69°F) and highs reaching up to 35°C (94°F). In contrast, January is considerably cooler, with average temperatures sitting at 11°C (52°F) and even dipping to a minimum of -7°C (19°F). Precipitation is more frequent in April, occurring on 9 days and totaling 89 mm (3.5 in), while January sees less rain with only 48 mm (1.9 in) over 6 days. Both months have similar humidity levels, hovering around 76% in April and slightly higher at 79% in January. For more detailed insights, you can visit San Marcos weather in January.

April and February showcase a distinct contrast in weather patterns. In April, temperatures range from a minimum of 3°C (38°F) to a maximum of 35°C (94°F), with an average temperature of 20°C (69°F). This month also experiences higher precipitation amounts, totaling 89 mm (3.5 in) over approximately 9 days, accompanied by a humidity level of 76%. In contrast, February features much colder temperatures, with a minimum of -15°C (6°F) and a maximum of 31°C (87°F), averaging 12°C (54°F). Precipitation is lower at 60 mm (2.4 in), spread over 10 days, and humidity levels are slightly higher at 79%. For more details on February weather, you can check San Marcos weather in February.

In comparing the weather between March and April, we see a notable increase in temperatures as spring progresses. April's minimum temperature starts at a milder 3°C (38°F), with averages reaching up to 20°C (69°F) and maximums peaking at 35°C (94°F). In contrast, March experiences cooler conditions, with minimums dropping to -3°C (27°F) and an average of 17°C (64°F), maxing out at 33°C (91°F). Precipitation levels also differ, with April receiving more rain at 89 mm (3.5 in) across 9 days, compared to March's 67 mm (2.6 in) over 11 days. Humidity remains relatively similar, with April at 76% and March at 74%. For those interested in more details, you can check out San Marcos weather in March.

In comparing the weather of April and May, we notice a significant increase in both temperature and precipitation. April features a minimum temperature of 3°C (38°F) and an average of 20°C (69°F), reaching a maximum of 35°C (94°F), accompanied by 89 mm (3.5 in) of rain over 9 days with a humidity of 76%. In contrast, May sees a rise in the minimum temperature to 10°C (51°F) and an average of 25°C (76°F), peaking at 36°C (98°F). Furthermore, May experiences a greater amount of rainfall, totaling 149 mm (5.9 in) over 14 days and slightly higher humidity at 81%. For a detailed look at the weather patterns in May, visit San Marcos weather in May.

April and June showcase a significant shift in weather patterns. April experiences cooler temperatures, with a minimum of 3°C (38°F) and an average of 20°C (69°F), while June boasts warmer conditions, starting at a minimum of 17°C (63°F) and reaching an average of 27°C (82°F). Both months have similar humidity levels at 76%, but June tends to be sunnier and hotter, with maximum temperatures hitting 37°C (100°F) compared to April's peak of 35°C (94°F). Additionally, June sees slightly more precipitation at 102 mm (4.0 in) over 12 days, compared to April's 89 mm (3.5 in) over 9 days. For more details, check out San Marcos weather in June.

April and July present a stark contrast in weather patterns. In April, temperatures vary more significantly, with a minimum of 3°C (38°F) and an average of 20°C (69°F), soaring to a maximum of 35°C (94°F). The month also experiences higher humidity at 76% and 89 mm (3.5 in) of precipitation over 9 days. In contrast, July offers a more stable warmth with a minimum temperature of 17°C (63°F), an average of 29°C (84°F), and a peak of 41°C (106°F). Despite being slightly drier with 79 mm (3.1 in) of precipitation also over 9 days, July boasts lower humidity at 66%, making for a more sultry atmosphere. For a detailed overview, check out San Marcos weather in July.

April and August present contrasting weather patterns. In April, temperatures fluctuate significantly, with minimums around 3°C (38°F) and maxima reaching 35°C (94°F), resulting in an average temperature of 20°C (69°F). This month also sees considerable precipitation, with about 89 mm (3.5 in) over 9 rainy days and relatively high humidity at 76%. In contrast, August boasts warmer temperatures, with a minimum of 20°C (68°F) and a maximum soaring to 40°C (104°F), leading to a higher average of 29°C (85°F). Rainfall in August is slightly higher at 111 mm (4.4 in), albeit over fewer days (7), and humidity drops to a more comfortable 58%. For more detailed insights, you can check the San Marcos weather in August.

April and September present distinct weather patterns. In April, temperatures range from a cooler minimum of 3°C (38°F) to an average of 20°C (69°F) and can reach highs of 35°C (94°F). The month is marked by relatively high humidity at 76% and moderate precipitation, with 89 mm (3.5 in) falling over about 9 days. In contrast, September boasts a warmer climate with minimum temperatures starting at 11°C (53°F) and an average of 26°C (79°F), occasionally peaking at a staggering 38°C (100°F). This month experiences slightly more rainfall at 112 mm (4.4 in) over 11 days, but the humidity is lower at 65%. For a closer look at the specifics, you can visit San Marcos weather in September.

April and October share similar temperature ranges, with both months featuring a minimum temperature around 3°C (38°F) and a maximum reaching up to 35°C (94°F in April and 96°F in October). The average temperature in April is slightly lower at 20°C (69°F), compared to October's 21°C (70°F). Precipitation is relatively consistent between the two months, with April receiving 89 mm (3.5 in) over 9 days and October seeing a slight increase to 94 mm (3.7 in) over 10 days. Humidity levels are also comparable, with April sitting at 76% and October slightly lower at 74%. For more detailed information, visit San Marcos weather in October.

April and November present contrasting weather patterns, showcasing a transition from warmth to cooler temperatures. In April, the average temperature reaches a pleasant 20°C (69°F) with highs climbing to 35°C (94°F), while November experiences a significantly cooler average of 15°C (60°F) and nighttime lows dropping to -3°C (26°F). Precipitation is more common in April, with 89 mm (3.5 in) of rain over 9 days, compared to November's 49 mm (1.9 in) over just 6 days. Interestingly, humidity levels are slightly higher in November at 81%, compared to April's 76%. For more specific details on November weather, you can refer to San Marcos weather in November.

April and December present contrasting weather patterns, with April experiencing a much warmer average temperature of 20°C (69°F) compared to December's average of 13°C (55°F). In April, temperatures can soar to a maximum of 35°C (94°F), while December's highs reach 29°C (84°F). Additionally, April sees more precipitation, totaling 89 mm (3.5 in) over about 9 days, versus December's 73 mm (2.9 in) over 7 days. Humidity levels are relatively high in both months, with April at 76% and December at 86%, contributing to a distinctly different climate experience. For more detailed information, you can explore San Marcos weather in December.

Compare San Marcos's Climate with Cities Worldwide

Conclusion: What to Expect From April Weather in San Marcos

April in San Marcos ushers in a delightful transition from the cooler months, with temperatures beginning to rise significantly. The average warmth creates a pleasant atmosphere, yet it remains accompanied by notable humidity levels, offering a perfect blend of springtime refreshment. This month also sees more rain than some of its predecessors, with frequent precipitation making the landscape lush and vibrant. Compared to other months, April stands out for its combination of warmth and moisture, inviting visitors to experience the beauty of nature in full bloom. For a deeper understanding of San Marcos weather throughout the year, visit San Marcos Climate.