Kailua in Summer
In summer (June, July and August), Kailua sees average daytime highs around 80°F and overnight lows near 74°F, with 3.5 in of rain over about 31 wet days across the season. It is the warmest season of the year and the driest season of the year.
Across summer, daytime highs hold fairly steady around 80°F. The sky is clear or mostly clear about 58% of the time across summer, and the air most often feels muggy.
Summer is Kailua's 3rd-best season to visit on our travel score. Kailua has little temperature swing across the year, so its calendar seasons blur — the season framing matters less here than for a place with four distinct seasons. For the whole year in context, see Kailua's year-round climate.
- Avg daytime high
- 80°F
- warmest season of the year
- Avg overnight low
- 74°F
- Rainfall
- 3.5 in
- 31 wet days
- Avg wind
- 14 mph
- Travel score
- 6.9
- 3rd-best season
- Months
- Jun · Jul · Aug
Temperature in Kailua in Summer
Across summer, daytime highs hold fairly steady around 80°F.
A typical summer day in Kailua reaches about 80°F and drops to 74°F overnight. The warmest of the three months is August, the coolest June.
Kailua 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.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 75° / 69° | 1.7 | 8.2 | 10.8 | 7.6 |
| Feb | 74° / 69° | 1.7 | 8.2 | 11.3 | 7.3 |
| Mar | 74° / 69° | 2.3 | 10.7 | 11.8 | 7.0 |
| Apr | 76° / 70° | 1.2 | 10.8 | 12.5 | 7.0 |
| May | 77° / 72° | 1.3 | 8.9 | 13 | 7.2 |
| Jun | 79° / 73° | 1.2 | 10.4 | 13.3 | 6.9 |
| Jul | 80° / 74° | 1.2 | 10.8 | 13.2 | 6.8 |
| Aug | 80° / 75° | 1.2 | 9.5 | 12.7 | 6.9 |
| Sep | 81° / 75° | 1.1 | 9.2 | 12.1 | 6.9 |
| Oct | 80° / 74° | 1.5 | 10 | 11.5 | 6.8 |
| Nov | 78° / 73° | 2.3 | 11.3 | 11 | 6.7 |
| Dec | 76° / 71° | 2.3 | 10.6 | 10.7 | 7.1 |
Cloud cover in Summer
The sky is clear or mostly clear about 58% of the time across summer.
Chance of precipitation in Summer
Kailua gets around 3.5 in of rain over 31 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 14 mph across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 h 12 min in early June to 12 h 30 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 7.0 kWh/m².
Hazard calendar for Kailua
In summer, Kailua overlaps its pacific hurricane season. The full year is below, with each hazard's peak months called out.
Kailua sits in the eastern Pacific hurricane zone; the season peaks August–September.
Is summer a good time to visit Kailua?
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.
summer is a reasonable time to visit Kailua for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Kailua in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Kailua sees daytime highs around 80°F and nights near 74°F. Pack sun protection. Worth having: light clothes, rain gear and a windbreaker. About 31 days see rain.
Sea temperature near Kailua in Summer
The nearest coast averages about 79°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 September at about 80°F and coldest in February near 75°F.
The water stays above 68°F all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 76 | 75 | 75 | 76 | 77 | 78 | 79 | 80 | 80 | 80 | 79 | 77 |
| Comfort | Warm | Refreshing | Refreshing | Warm | Warm | Warm | Warm | Warm | Warm | Warm | Warm | Warm |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 76 | Warm |
| Feb | 75 | Refreshing |
| Mar | 75 | Refreshing |
| Apr | 76 | Warm |
| May | 77 | Warm |
| Jun | 78 | Warm |
| Jul | 79 | Warm |
| Aug | 80 | Warm |
| Sep | 80 | Warm |
| Oct | 80 | Warm |
| Nov | 79 | Warm |
| Dec | 77 | Warm |
UV index in Kailua in Summer
Clear-sky midday UV across summer averages around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Kailua peaks around July 22 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 6 (high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 6 | 8 | 10 | 11 | 10 | 11 | 12 | 12 | 12 | 9 | 7 | 6 |
| Level | High | Very high | Extreme | Extreme | Very high | Extreme | Extreme | Extreme | Extreme | Very high | High | High |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 6 | High |
| Feb | 8 | Very high |
| Mar | 10 | Extreme |
| Apr | 11 | Extreme |
| May | 10 | Very high |
| Jun | 11 | Extreme |
| Jul | 12 | Extreme |
| Aug | 12 | Extreme |
| Sep | 12 | Extreme |
| Oct | 9 | Very high |
| Nov | 7 | High |
| Dec | 6 | High |
Where is Kailua?
Kailua sits at 21.4°N, 157.7°W, 33 ft above sea level, in United States. The nearest listed city is Kaneohe, 3.7 mi away.
Topography around Kailua
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Kailua.
Within 2 miles, the terrain around Kailua has only modest variations in elevation — a maximum elevation change of 545 ft around an average of 39 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,117 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 3,983 ft.
The land around Kailua is covered by water (33%) and artificial surfaces (26%) within 2 miles, water (56%) and trees (27%) within 10 miles, and water (86%) within 50 miles.
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
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 Kailua (21.4024°, -157.7405°, 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.