Casa de Oro-Mount Helix in Summer

In summer (June, July and August), Casa de Oro-Mount Helix sees average daytime highs around 78°F and overnight lows near 63°F, with 0.2 in of rain over about 2 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 Casa de Oro-Mount Helix's best season of the year to visit on our travel score. For the whole year in context, see Casa de Oro-Mount Helix's year-round climate.

Avg daytime high
78°F
warmest season of the year
Avg overnight low
63°F
Rainfall
0.2 in
2 wet days
Avg wind
5 mph
Travel score
8.9
best season of the year
Months
Jun · Jul · Aug

Temperature in Casa de Oro-Mount Helix 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 Casa de Oro-Mount Helix reaches about 78°F and drops to 63°F overnight. The warmest of the three months is August, the coolest June.

50°60°70°80°90°JunJulAug

Casa de Oro-Mount Helix 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° / 48°2.35.610.16.8
Feb64° / 48°2.9710.86.3
Mar65° / 50°1.95.811.86.8
Apr68° / 53°0.93.912.87.6
May70° / 56°0.4213.78.2
Jun74° / 60°0.10.614.19.2
Jul79° / 64°0.10.713.98.9
Aug81° / 65°0.10.513.28.7
Sep80° / 64°0.20.912.28.8
Oct76° / 59°0.62.511.28.7
Nov70° / 53°0.93.310.37.9
Dec64° / 48°1.95.29.96.8

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

Casa de Oro-Mount Helix gets around 0.2 in of rain over 2 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 hours in early June to 12 h 42 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 Casa de Oro-Mount Helix?

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.

8.9
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 Casa de Oro-Mount Helix for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Casa de Oro-Mount Helix in Summer

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

In summer, Casa de Oro-Mount Helix sees daytime highs around 78°F and nights near 63°F. Pack light clothes and sun protection.

light clothessun protection

Sea temperature near Casa de Oro-Mount Helix 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 at the nearest coast (about 13 mi away) is warmest in August at about 70°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
Jan60Cool
Feb59Cool
Mar60Cool
Apr61Cool
May63Cool
Jun65Cool
Jul68Refreshing
Aug70Refreshing
Sep69Refreshing
Oct67Cool
Nov64Cool
Dec61Cool

UV index in Casa de Oro-Mount Helix in Summer

LowModerateHighVery highExtreme

Clear-sky midday UV across summer averages around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Casa de Oro-Mount Helix peaks around June 22 at about 11 (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 — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 22UV 11Dec 17UV 3
UV index (midday)Level
Jan4Moderate
Feb5Moderate
Mar5High
Apr8Very high
May8Very high
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Casa de Oro-Mount Helix 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 Casa de Oro-Mount Helix is worst in September — around 26 µg/m³ PM2.5 (moderate), about 3.4× the cleanest month (May, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateSep 1625 µg/m³May 168 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb12Moderate
Mar12Moderate
Apr11Good
May8Good
Jun11Good
Jul11Good
Aug15Moderate
Sep26Moderate
Oct14Moderate
Nov12Moderate
Dec16Moderate
Location & terrain

Where is Casa de Oro-Mount Helix?

Casa de Oro-Mount Helix sits at 32.8°N, 117.0°W, 840 ft above sea level, in United States. The nearest listed city is El Cajon, 1.9 mi away.

Topography around Casa de Oro-Mount Helix

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Casa de Oro-Mount Helix.

Within 2 miles, the terrain around Casa de Oro-Mount Helix has significant variations in elevation — a maximum elevation change of 932 ft around an average of 643 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,762 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 6,430 ft.

The land around Casa de Oro-Mount Helix is covered by artificial surfaces (59%) and trees (31%) within 2 miles, artificial surfaces (40%) and shrubs (26%) within 10 miles, and shrubs (27%) and water (27%) within 50 miles.

2 miles
932 ft
10 miles
2,762 ft
50 miles
6,430 ft
treesshrubsgrasslandartificial surfacesbare terrainwater
Summer weather nearby: El Cajon 1.9 mi · Spring Valley 2.5 mi · Rancho San Diego 2.5 mi · La Mesa 3.1 mi · Bostonia 3.7 mi · Lemon Grove 3.7 mi · La Presa 4.3 mi · Winter Gardens 5.0 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 Casa de Oro-Mount Helix (32.764°, -116.9688°, elevation 840 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.