Fountain Valley in Summer

In summer (June, July and August), Fountain Valley sees average daytime highs around 78°F and overnight lows near 64°F, with 0.1 in of rain over about 1 wet days across the season. It is the warmest season of the year and the driest season of the year.

Over the season highs climb from about 72°F in early June to 82°F by late August. The sky is clear or mostly clear about 84% of the time across summer, and the air most often feels comfortable.

Summer is Fountain Valley's best season of the year to visit on our travel score. For the whole year in context, see Fountain Valley's year-round climate.

Avg daytime high
78°F
warmest season of the year
Avg overnight low
64°F
Rainfall
0.1 in
1 wet days
Avg wind
5 mph
Travel score
9.0
best season of the year
Months
Jun · Jul · Aug

Temperature in Fountain Valley in Summer

Average highAverage lowShaded bands: 10–90% of days

Over the season highs climb from about 72°F in early June to 82°F by late August.

A typical summer day in Fountain Valley reaches about 78°F and drops to 64°F overnight. The warmest of the three months is August, the coolest June.

50°60°70°80°90°JunJulAug

Fountain Valley weather by month

How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan64° / 49°2.85.2106.8
Feb65° / 50°3.16.110.76.7
Mar66° / 53°1.85.111.77.0
Apr69° / 55°0.72.612.87.9
May71° / 58°0.31.513.78.3
Jun74° / 61°0.10.314.29.1
Jul79° / 64°0.10.4149.0
Aug81° / 65°0.00.113.38.9
Sep80° / 64°0.10.512.28.8
Oct76° / 60°0.61.911.28.8
Nov70° / 54°0.72.410.38.1
Dec65° / 49°1.94.99.86.9

Cloud cover in Summer

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 84% of the time across summer.

0%25%50%75%100%JunJulAug

Chance of precipitation in Summer

Any precipitation

Fountain Valley gets around 0.1 in of rain over 1 wet days across summer. The line is the day-by-day chance of measurable precipitation.

0%10%20%30%JunJulAug

Humidity in Summer

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%JunJulAug

Wind in Summer

Winds average 5 mph across summer.

0246810JunJulAug

Sunrise & sunset in Summer

DaylightNight

Daylight runs from about 14 h 06 min in early June to 12 h 48 min by late August. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJunJulAug

Solar energy in Summer

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across summer, about 7.7 kWh/m².

02468JunJulAug
Planning a trip in summer

Is summer a good time to visit Fountain Valley?

Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

9.0
Sightseeing
1st-best month of the year
8.3
Beach & pool
1st-best month of the year

summer is one of the better times to visit Fountain Valley for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Fountain Valley in Summer

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

In summer, Fountain Valley sees daytime highs around 78°F and nights near 64°F. Pack light clothes and sun protection.

light clothessun protection

Sea temperature near Fountain Valley in Summer

The nearest coast averages about 68°F across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 69°F and coldest in February near 59°F.

It's comfortable for a long swim from Jul 13 to Sep 28 — about 2.6 months when the water holds above 68°F.

60°65°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingcomfortable to swim
Sea temperature (°F)Comfort
Jan59Cool
Feb59Cool
Mar59Cool
Apr60Cool
May63Cool
Jun65Cool
Jul68Refreshing
Aug69Refreshing
Sep69Refreshing
Oct67Cool
Nov64Cool
Dec60Cool

UV index in Fountain Valley in Summer

LowModerateHighVery highExtreme

Clear-sky midday UV across summer averages 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 Fountain Valley peaks around June 23 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 23UV 10Dec 17UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar5Moderate
Apr7Very high
May8Very high
Jun10Extreme
Jul10Extreme
Aug10Extreme
Sep8Very high
Oct6High
Nov3Moderate
Dec3Moderate

Air quality in Fountain Valley in Summer

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Fountain Valley is worst in September — around 49 µg/m³ PM2.5 (poor), about 4.0× the cleanest month (May, 12 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateSep 1447 µg/m³May 1713 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb19Moderate
Mar19Moderate
Apr17Moderate
May12Moderate
Jun17Moderate
Jul19Moderate
Aug32Moderate
Sep49Poor
Oct21Moderate
Nov21Moderate
Dec18Moderate
Location & terrain

Where is Fountain Valley?

Fountain Valley sits at 33.7°N, 118.0°W, 33 ft above sea level, in United States. The nearest listed city is Huntington Beach, 4.3 mi away.

Topography around Fountain Valley

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

Within 2 miles, the terrain around Fountain Valley has only modest variations in elevation — a maximum elevation change of 69 ft around an average of 36 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 751 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 9,967 ft.

The land around Fountain Valley is covered by artificial surfaces (85%) within 2 miles, artificial surfaces (62%) and water (26%) within 10 miles, and water (40%) and artificial surfaces (25%) within 50 miles.

2 miles
69 ft
10 miles
751 ft
50 miles
9,967 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetland
Summer weather nearby: Huntington Beach 4.3 mi · Garden Grove 4.3 mi · Westminster 4.3 mi · Costa Mesa 5.0 mi · Santa Ana 5.6 mi · Newport Beach 6.2 mi · Stanton 6.8 mi · Tustin Legacy 7.5 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 Fountain Valley (33.7092°, -117.9537°, elevation 33 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.