Los Altos weather in April

In April, Los Altos sees average daytime highs of 65°F and overnight lows near 48°F, with 1.6 in of rain across 5.7 wet days and about 12.9 hours of daylight. It is the 7th-warmest and 6th-wettest month of the year here.

Highs climb over the month, from about 63°F in the first days to 68°F by the end. The sky is clear or mostly clear about 45% of the time in April, and the air most often feels dry.

Daylight stretches from about 12 h 24 min at the start of April to 13 h 30 min by month's end. Set against the rest of the year, April is Los Altos's 8th-clearest and 2nd-windiest month. For the whole year in context, see Los Altos's year-round climate.

Daytime high
65°
7th warmest
Overnight low
48°
6th coldest
Rainfall
1.6 in
5.7 wet days
Daylight
13 hours
5:40 AM – 6:37 PM
Cloud cover
47%
8th clearest
Wind
5 mph
2nd windiest
Solar energy
6.24 kWh/m²
Travel score
6.8
out of 10

Los Altos is city in Santa Clara County, California, United States.

Density
1,829/km²
people per km²
Founded
1952

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 63°F in the first days to 68°F by the end.

A typical April day in Los Altos reaches about 65°F in the afternoon and slips back to 48°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 57°F and 76°F. Set against its neighbours, April runs about 3°F warmer than March and about 5°F cooler than May.

40°50°60°70°80°151015202530
Avg high (°F)Avg low (°F)
16347
26347
36347
46347
56347
66447
76447
86447
96447
106447
116447
126448
136448
146548
156548
166548
176548
186648
196649
206649
216649
226749
236749
246749
256749
266849
276850
286850
296850
306850

Los Altos weather by month

How April compares with the rest of the year at a glance. April is the 7th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan57° / 43°3.68.99.74.2
Feb59° / 45°3.88.910.64.7
Mar62° / 47°2.99.111.75.6
Apr65° / 48°1.65.712.96.8
May70° / 52°0.83.4147.9
Jun76° / 55°0.20.914.59.1
Jul80° / 58°0.00.214.39.0
Aug81° / 59°0.00.213.48.9
Sep79° / 58°0.10.412.39.0
Oct73° / 54°0.92.9118.5
Nov63° / 48°1.75.7106.3
Dec57° / 43°3.38.99.54.2

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 45% 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 40%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15446
25446
35446
45545
55545
65545
75545
85545
95545
105644
115743
125743
135842
145941
155941
166040
176139
186139
196238
206238
216436
226436
236436
246436
256535
266535
276634
286634
296634
306634

Chance of precipitation in April

Any precipitation

Los Altos gets around 1.6 in of rain over 5.7 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 19% and peaks near 23% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202530
Rain chance (%)
123
223
323
423
523
622
722
822
922
1022
1122
1221
1321
1420
1520
1619
1719
1818
1918
2017
2117
2216
2316
2415
2515
2615
2714
2814
2914
3013

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 97% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10982
11982
12982
13982
14982
15973
16973
17973
18973
19973
20964
21964
22964
23964
24964
25955
26955
27955
28955
29955
30955

Wind in April

Winds average 5 mph in April.

Across April, daily wind ranges from about 5 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 24 min at the start of April to 13 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 66 minutes over April. Sunrise moves from 6:02 AM to 5:21 AM, and sunset from 6:24 PM to 6:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.46:026:24
212.46:016:25
312.45:596:26
412.55:586:27
512.55:566:28
612.65:556:28
712.65:536:29
812.65:526:30
912.75:506:31
1012.75:496:32
1112.85:476:33
1212.85:466:34
1312.85:446:35
1412.95:436:36
1512.95:416:37
1613.05:406:37
1713.05:386:38
1813.05:376:39
1913.15:366:40
2013.15:346:41
2113.25:336:42
2213.25:326:43
2313.25:306:44
2413.35:296:45
2513.35:286:46
2613.35:266:47
2713.45:256:48
2813.45:246:48
2913.45:226:49
3013.55:216:50

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 6.24 kWh/m².

For context, solar energy here swings from a low near 2.29 kWh/m² to a high of 7.96 kWh/m² in June across the year — April's 6.24 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.6Bright
25.6Bright
35.7Bright
45.7Bright
55.8Bright
65.8Bright
75.8Bright
85.9Bright
95.9Bright
106.0Bright
116.0Intense
126.1Intense
136.1Intense
146.2Intense
156.2Intense
166.3Intense
176.3Intense
186.3Intense
196.4Intense
206.5Intense
216.5Intense
226.5Intense
236.6Intense
246.6Intense
256.7Intense
266.7Intense
276.7Intense
286.8Intense
296.8Intense
306.8Intense
Planning a trip in April

Is April a good time to visit Los Altos?

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

6.8
Sightseeing
7th-best month of the year
2.7
Beach & pool
7th-best month of the year

April is a reasonable time to visit Los Altos for sightseeing.

What to pack for Los Altos in April

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

In April, Los Altos sees daytime highs around 65°F and nights near 48°F. Pack sun protection. About 6 days see rain.

sun protection

Sea temperature near Los Altos in April

The nearest coast averages about 54°F in April — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 14 mi away) is warmest in August at about 59°F and coldest in April near 54°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

52°54°56°58°60°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°F)Comfort
Jan54Bracing
Feb54Bracing
Mar54Bracing
Apr54Bracing
May54Bracing
Jun55Bracing
Jul57Bracing
Aug59Bracing
Sep59Bracing
Oct58Bracing
Nov56Bracing
Dec55Bracing

UV index in Los Altos in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Los Altos peaks around June 23 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 23UV 10Dec 15UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun10Extreme
Jul10Extreme
Aug10Very high
Sep6High
Oct5High
Nov2Moderate
Dec2Moderate

Air quality in Los Altos 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 Los Altos is worst in August — around 25 µg/m³ PM2.5 (moderate), about 2.5× the cleanest month (June, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateAug 1824 µg/m³Jun 1110 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb18Moderate
Mar16Moderate
Apr12Moderate
May10Good
Jun10Good
Jul11Good
Aug25Moderate
Sep17Moderate
Oct20Moderate
Nov18Moderate
Dec13Moderate
Location & terrain

Where is Los Altos?

Los Altos sits at 37.4°N, 122.1°W, 157 ft above sea level, in United States. The nearest listed city is Mountain View, 1.9 mi away.

Topography around Los Altos

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

Within 2 miles, the terrain around Los Altos has only modest variations in elevation — a maximum elevation change of 505 ft around an average of 177 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,002 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,452 ft.

The land around Los Altos is covered by artificial surfaces (48%) and trees (47%) within 2 miles, trees (43%) and artificial surfaces (28%) within 10 miles, and water (36%), trees (25%) and grassland (23%) within 50 miles.

2 miles
505 ft
10 miles
3,002 ft
50 miles
4,452 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
April weather nearby: Mountain View 1.9 mi · Palo Alto 4.3 mi · Sunnyvale 4.3 mi · East Palo Alto 6.2 mi · Menlo Park 6.2 mi · Cupertino 6.2 mi · Santa Clara 8.7 mi · Redwood City 9.3 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 Los Altos (37.3852°, -122.1141°, elevation 157 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).