Kailua-Kona, HI weather in September
Expect warm, mostly dry weather in Kailua-Kona in September, with highs near 87°F and lows near 75°F. Rain falls on about 6 days.
- Normal high
- 87°F
- Normal low
- 75°F
- Wet days
- 6
- 1.8 in total
- Daylight
- 12.3 h
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 87°F | 87°F |
| Normal low | 75°F | 75°F |
| Chance of a wet day | 19% | 18% |
| Sunrise / sunset | 6:08 am / 6:39 pm | 6:14 am / 6:13 pm |
| Daylight | 12.5 h | 12.0 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Hawaii time (no daylight saving)).
What kind of days to expect
- Comfortable dayshigh 65-80°F (temperature only: no humidity station nearby)0 of 30
- Beach dayshigh 80-95°F, under 0.05 in of rain (temperature and rain only)25 of 30
- Hot dayshigh 90°F or more2 of 30
- Wet daysat least 0.01 in of rain or melted snow6 of 30
- Notable rainat least 0.10 in4 of 30
- Freezing nightslow 32°F or below0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 1.8 in; a dry September brings about 0.5 in and a wet one about 2.3 in (25th and 75th percentiles). About 1 day brings half an inch or more.
How September varies from year to year
- Warmest September, 1991-20202015: average high 91°F
- Coolest September2010: average high 85°F
- Wettest September2015: 8.8 in
- Driest September2002: no measurable precipitation
- Highest reading96°F (September 25, 2015)
- Lowest reading65°F (September 26, 2019)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 87°F | 87°F | 86°F |
| Normal low | 76°F | 75°F | 75°F |
| Wet days | 5 | 6 | 4 |
| Comfortable days | 0 | 0 | 0 |
| Daylight | 12.8 h | 12.3 h | 11.7 h |
Highs change by 0°F from August and -1°F into October.
How Kailua-Kona ranks in September
- Normal high118th warmest of 378 cities; 3rd of 7 in Hawaii
- Wet days103rd driest of 378
What to pack for Kailua-Kona in September
- Light, breathable clothing – highs near 87°F
- A swimsuit – about 25 beach days
Heating and cooling
September has 0 heating degree days and 480 cooling degree days (base 65°F), 10% of the year's total heating and cooling demand.
Questions
How hot is Kailua-Kona in September?
The normal high is 87°F and the normal low is 75°F. From 1991 to 2020 the hottest September reading was 96°F (September 25, 2015).
Does it rain a lot in Kailua-Kona in September?
About 6 days in September have at least 0.01 in of precipitation, and the normal total is 1.8 in. The wettest September in 1991-2020 was in 2015 (8.8 in); the driest was in 2002, with no measurable precipitation.
Is September a good time to visit Kailua-Kona?
September ranks 12th of 12 months on our comfort score for Kailua-Kona (48 out of 100). It has almost no comfortable days (judged by temperature only) and about 2 days at 90°F or hotter. The best months are January, February and March.
Where the numbers come from
- Temperature and frost dates: Kailua Kona Ke-Ahole Airport (USW00021510), 7.7 mi NNW of the city center, 43 ft . NOAA normals and daily records, 1991-2020.
- Rain, snowfall and snow depth: Honokohau Harbor 68.14 (USC00511880), 3.4 mi NW of the city center, 30 ft . NOAA normals and daily records, 1991-2020.
- Not available for this location: humidity and wind by hour, cloud cover and daily humidity and wind (no station close enough or similar enough in elevation).