San Marcos weather in April

In April, San Marcos sees average daytime highs of 78°F and overnight lows near 59°F, with 3.3 in of rain across 9 wet days and about 12.7 hours of daylight. It is the 7th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 75°F in the first days to 81°F by the end. The sky is clear or mostly clear about 37% of the time in April, and the air most often feels dry.

Daylight stretches from about 12 h 18 min at the start of April to 13 h 06 min by month's end. Set against the rest of the year, April is San Marcos's 7th-clearest and 1st-windiest month. For the whole year in context, see San Marcos's year-round climate.

Daytime high
78°
7th warmest
Overnight low
59°
6th coldest
Rainfall
3.3 in
9 wet days
Daylight
12 h 42 min
6:10 AM – 6:54 PM
Cloud cover
53%
7th clearest
Wind
9 mph
1st windiest
Solar energy
5.45 kWh/m²
Travel score
6.9
out of 10

San Marcos is city in and county seat of Hays County, Texas, United States, that extends into Caldwell and Guadalupe counties.

Density
684/km²
people per km²
Founded
1808

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 75°F in the first days to 81°F by the end.

A typical April day in San Marcos reaches about 78°F in the afternoon and slips back to 59°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 69°F and 86°F. Set against its neighbours, April runs about 7°F warmer than March and about 6°F cooler than May.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17556
27556
37556
47656
57656
67656
77656
87657
97757
107757
117757
127758
137858
147858
157858
167859
177959
187959
197959
207960
218060
228060
238060
248061
258061
268161
278161
288162
298162
308262

How April really feels in San Marcos

Once humidity and wind are folded in, April averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

April sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

San Marcos weather by month

How April compares with the rest of the year at a glance. April is the 7th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan61° / 42°2.57.410.35.4
Feb65° / 46°2.47.610.96.2
Mar71° / 52°3.09.411.86.8
Apr78° / 59°3.3912.76.9
May85° / 66°4.511.413.55.3
Jun90° / 72°3.29.813.93.9
Jul94° / 74°1.86.413.73.2
Aug94° / 74°2.46.413.13.0
Sep88° / 69°3.08.212.24.7
Oct80° / 60°3.27.511.37.1
Nov69° / 50°2.8710.57.0
Dec62° / 43°2.87.910.15.7

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 15% of April, with mostly cloudy or overcast conditions the remaining 48%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14852
24951
34951
44951
55050
65149
75248
85248
95347
105347
115446
125446
135545
145446
155446
165446
175446
185446
195446
205347
215347
225347
235248
245248
255149
265248
275149
285050
295050
305050

Chance of precipitation in April

Any precipitation

San Marcos gets around 3.3 in of rain over 9 wet days in April. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 30% and peaks near 34% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
132
232
332
431
531
631
730
830
929
1029
1128
1228
1328
1427
1527
1627
1728
1828
1928
2029
2129
2230
2330
2431
2531
2632
2732
2833
2933
3034

Humidity in April

DryComfortableHumidMuggyOppressiveMiserable

Most of April feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, April lands in the dry band about 40% of days. Sticky, muggy-or-worse air turns up on roughly 22% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1481920130
2481920140
3481819140
4471819150
5471819150
6471820160
7461820160
8461820160
9451720170
10451721170
11441721180
12431721181
13421722191
14421722191
15411722201
16401723201
17391623211
18381623211
19381623221
20371623231
21361623232
22351623242
23351523252
24341523252
25331523263
26331423273
27321423284
28311322294
29311322295
30301222306

Wind in April

Winds average 9 mph in April, the windiest month of the year.

Across April, daily wind ranges from about 9 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 18 min at the start of April to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 48 minutes over April. Sunrise moves from 6:28 AM to 5:56 AM, and sunset from 6:45 PM to 7:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.36:286:45
212.36:276:45
312.36:266:46
412.46:256:46
512.46:236:47
612.46:226:48
712.56:216:48
812.56:206:49
912.56:196:49
1012.56:176:50
1112.66:166:51
1212.66:156:51
1312.66:146:52
1412.76:136:52
1512.76:116:53
1612.76:106:54
1712.86:096:54
1812.86:086:55
1912.86:076:55
2012.86:066:56
2112.96:056:57
2212.96:046:57
2312.96:036:58
2413.06:026:59
2513.06:016:59
2613.06:007:00
2713.05:597:01
2813.15:587:01
2913.15:577:02
3013.15:567:03

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 5.45 kWh/m².

For context, solar energy here swings from a low near 2.69 kWh/m² to a high of 6.69 kWh/m² in July across the year — April's 5.45 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
14.9Bright
25.0Bright
35.0Bright
45.1Bright
55.1Bright
65.1Bright
75.2Bright
85.2Bright
95.3Bright
105.3Bright
115.3Bright
125.4Bright
135.4Bright
145.4Bright
155.5Bright
165.5Bright
175.5Bright
185.5Bright
195.5Bright
205.5Bright
215.6Bright
225.6Bright
235.6Bright
245.6Bright
255.6Bright
265.6Bright
275.6Bright
285.6Bright
295.6Bright
305.6Bright
Planning a trip in April

Is April a good time to visit San Marcos?

Our two travel scores rate April for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.9
Sightseeing
3rd-best month of the year
6.5
Beach & pool
4th-best month of the year

April is a reasonable time to visit San Marcos for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for San Marcos in April

From April's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In April, San Marcos sees daytime highs around 78°F and nights near 59°F. Worth packing: light clothes, rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

UV index in San Marcos in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in San Marcos peaks around August 11 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 4 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateAug 11UV 11Dec 20UV 4
UV index (midday)Level
Jan4Moderate
Feb6High
Mar7High
Apr10Very high
May10Extreme
Jun10Extreme
Jul10Extreme
Aug11Extreme
Sep9Very high
Oct6High
Nov5Moderate
Dec4Moderate

Air quality in San Marcos in April

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where April falls, not just the annual average.

Air quality in San Marcos is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.9× the cleanest month (December, 6 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1416 µg/m³Dec 136 µg/m³
PM2.5 (µg/m³)Level
Jan6Good
Feb7Good
Mar8Good
Apr9Good
May14Moderate
Jun14Moderate
Jul17Moderate
Aug12Good
Sep10Good
Oct6Good
Nov6Good
Dec6Good
Location & terrain

Where is San Marcos?

San Marcos sits at 29.9°N, 97.9°W, 617 ft above sea level, in United States. The nearest listed city is Kyle, 8.1 mi away.

Topography around San Marcos

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of San Marcos.

Within 2 miles, the terrain around San Marcos has only modest variations in elevation — a maximum elevation change of 289 ft around an average of 643 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 751 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,814 ft.

The land around San Marcos is covered by trees (42%), artificial surfaces (31%) and grassland (23%) within 2 miles, trees (41%) and grassland (39%) within 10 miles, and trees (48%) and grassland (42%) within 50 miles.

2 miles
289 ft
10 miles
751 ft
50 miles
1,814 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
April weather nearby: Kyle 8.1 mi · New Braunfels 17 mi · Canyon Lake 19 mi · Seguin 22 mi · Cibolo 28 mi · Austin 29 mi · Schertz 30 mi · University of Texas 30 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for San Marcos (29.8833°, -97.9414°, elevation 617 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).