Iwata weather in September
In September, Iwata sees average daytime highs of 28°C and overnight lows near 22°C, with 247 mm of rain across 15.8 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 3rd-wettest month of the year here.
Highs ease over the month, from about 30°C in the first days to 26°C by the end. The sky is clear or mostly clear about 29% of the time in September, and the air most often feels muggy.
Daylight stretches from about 12 h 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Iwata's 9th-clearest and 10th-windiest month. For the whole year in context, see Iwata's year-round climate.
- Daytime high
- 28°
- 3rd warmest
- Overnight low
- 22°
- 10th coldest
- Rainfall
- 247 mm
- 15.8 wet days
- Daylight
- 12 h 12 min
- 5:37 AM – 5:49 PM
- Cloud cover
- 62%
- 9th clearest
- Wind
- 10 km/h
- 10th windiest
- Solar energy
- 4.09 kWh/m²
- Travel score
- 5.1
- out of 10
Iwata is city in Shizuoka prefecture, Japan.
- Founded
- 2005
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in September
Highs ease over the month, from about 30°C in the first days to 26°C by the end.
A typical September day in Iwata reaches about 28°C in the afternoon and slips back to 22°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 31°C. Set against its neighbours, September runs about 3°C cooler than August and about 5°C warmer than October.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 30 | 30 | 30 | 30 | 30 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 28 | 28 | 28 | 28 | 28 | 27 | 27 | 27 | 27 | 27 | 27 | 26 | 26 | 26 | 26 | 26 | 26 | 25 |
| Avg low (°C) | 24 | 24 | 24 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 22 | 22 | 22 | 22 | 22 | 22 | 21 | 21 | 21 | 21 | 21 | 21 | 20 | 20 | 20 | 20 | 20 | 19 | 19 | 19 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 30 | 24 |
| 2 | 30 | 24 |
| 3 | 30 | 24 |
| 4 | 30 | 23 |
| 5 | 30 | 23 |
| 6 | 29 | 23 |
| 7 | 29 | 23 |
| 8 | 29 | 23 |
| 9 | 29 | 23 |
| 10 | 29 | 23 |
| 11 | 29 | 22 |
| 12 | 29 | 22 |
| 13 | 28 | 22 |
| 14 | 28 | 22 |
| 15 | 28 | 22 |
| 16 | 28 | 22 |
| 17 | 28 | 21 |
| 18 | 27 | 21 |
| 19 | 27 | 21 |
| 20 | 27 | 21 |
| 21 | 27 | 21 |
| 22 | 27 | 21 |
| 23 | 27 | 20 |
| 24 | 26 | 20 |
| 25 | 26 | 20 |
| 26 | 26 | 20 |
| 27 | 26 | 20 |
| 28 | 26 | 19 |
| 29 | 26 | 19 |
| 30 | 25 | 19 |
How September really feels in Iwata
Once humidity and wind are folded in, September averages 5 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.
The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Iwata weather by month
How September compares with the rest of the year at a glance. September is the 3rd-warmest and 3rd-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 10° / 3° | 70 | 5.9 | 0.1 | 9.9 | 2.7 |
| Feb | 11° / 3° | 89 | 6.9 | 0.5 | 10.7 | 3.1 |
| Mar | 14° / 6° | 148 | 10.8 | 0.1 | 11.7 | 4.3 |
| Apr | 19° / 10° | 165 | 11.1 | 0 | 12.8 | 5.9 |
| May | 23° / 15° | 184 | 12 | 0 | 13.8 | 6.4 |
| Jun | 26° / 20° | 258 | 15.7 | 0 | 14.3 | 5.4 |
| Jul | 30° / 24° | 273 | 16.9 | 0 | 14.1 | 4.2 |
| Aug | 31° / 25° | 157 | 16.2 | 0 | 13.3 | 3.8 |
| Sep | 28° / 22° | 247 | 15.8 | 0 | 12.2 | 5.1 |
| Oct | 23° / 16° | 216 | 12.5 | 0 | 11.1 | 6.4 |
| Nov | 18° / 10° | 122 | 9.2 | 0 | 10.2 | 5.9 |
| Dec | 13° / 5° | 71 | 6.6 | 0 | 9.7 | 3.9 |
Cloud cover in September
The sky is clear or mostly clear about 29% of the time in September.
Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 57%.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 45 | 45 | 46 | 45 | 45 | 44 | 43 | 43 | 44 | 44 | 43 | 43 | 43 | 43 | 43 | 43 | 43 | 42 | 42 | 43 | 42 | 41 | 41 | 43 | 43 | 43 | 42 | 42 | 43 | 43 |
| Cloudier (%) | 55 | 55 | 54 | 55 | 55 | 56 | 57 | 57 | 56 | 56 | 57 | 57 | 57 | 57 | 57 | 57 | 57 | 58 | 58 | 57 | 58 | 59 | 59 | 57 | 57 | 57 | 58 | 58 | 57 | 57 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 45 | 55 |
| 2 | 45 | 55 |
| 3 | 46 | 54 |
| 4 | 45 | 55 |
| 5 | 45 | 55 |
| 6 | 44 | 56 |
| 7 | 43 | 57 |
| 8 | 43 | 57 |
| 9 | 44 | 56 |
| 10 | 44 | 56 |
| 11 | 43 | 57 |
| 12 | 43 | 57 |
| 13 | 43 | 57 |
| 14 | 43 | 57 |
| 15 | 43 | 57 |
| 16 | 43 | 57 |
| 17 | 43 | 57 |
| 18 | 42 | 58 |
| 19 | 42 | 58 |
| 20 | 43 | 57 |
| 21 | 42 | 58 |
| 22 | 41 | 59 |
| 23 | 41 | 59 |
| 24 | 43 | 57 |
| 25 | 43 | 57 |
| 26 | 43 | 57 |
| 27 | 42 | 58 |
| 28 | 42 | 58 |
| 29 | 43 | 57 |
| 30 | 43 | 57 |
Chance of precipitation in September
Iwata gets around 247 mm of rain over 15.8 wet days in September. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 53% and peaks near 55% on the wettest days.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 52 | 52 | 53 | 53 | 54 | 54 | 54 | 54 | 55 | 55 | 55 | 54 | 54 | 54 | 53 | 53 | 53 | 53 | 53 | 53 | 52 | 52 | 52 | 51 | 51 | 51 | 51 | 51 | 50 | 50 |
| Rain chance (%) | |
|---|---|
| 1 | 52 |
| 2 | 52 |
| 3 | 53 |
| 4 | 53 |
| 5 | 54 |
| 6 | 54 |
| 7 | 54 |
| 8 | 54 |
| 9 | 55 |
| 10 | 55 |
| 11 | 55 |
| 12 | 54 |
| 13 | 54 |
| 14 | 54 |
| 15 | 53 |
| 16 | 53 |
| 17 | 53 |
| 18 | 53 |
| 19 | 53 |
| 20 | 53 |
| 21 | 52 |
| 22 | 52 |
| 23 | 52 |
| 24 | 51 |
| 25 | 51 |
| 26 | 51 |
| 27 | 51 |
| 28 | 51 |
| 29 | 50 |
| 30 | 50 |
Humidity in September
Most of September feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the muggy band about 32% of days. Sticky, muggy-or-worse air turns up on roughly 68% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 3 | 3 | 4 | 4 | 5 | 5 | 6 | 7 | 7 | 8 | 9 | 10 |
| Comfortable (%) | 1 | 2 | 2 | 2 | 2 | 3 | 3 | 3 | 4 | 4 | 5 | 5 | 6 | 7 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 13 | 14 | 15 | 16 | 17 | 17 | 18 | 19 | 20 |
| Humid (%) | 7 | 7 | 7 | 8 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 18 | 19 | 20 | 22 | 23 | 24 | 25 | 26 | 28 | 29 | 30 | 31 | 32 | 34 | 34 | 34 | 35 |
| Muggy (%) | 26 | 27 | 28 | 28 | 29 | 30 | 30 | 31 | 31 | 32 | 32 | 32 | 33 | 33 | 34 | 34 | 35 | 35 | 35 | 36 | 35 | 35 | 35 | 35 | 34 | 33 | 33 | 31 | 30 | 29 |
| Oppressive (%) | 55 | 53 | 53 | 52 | 51 | 49 | 48 | 47 | 45 | 44 | 42 | 40 | 38 | 36 | 34 | 32 | 29 | 27 | 25 | 22 | 20 | 18 | 16 | 14 | 13 | 11 | 9 | 8 | 7 | 6 |
| Miserable (%) | 11 | 11 | 10 | 10 | 10 | 9 | 9 | 8 | 8 | 7 | 7 | 6 | 5 | 5 | 4 | 4 | 3 | 3 | 2 | 2 | 2 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| 1 | 0 | 1 | 7 | 26 | 55 | 11 |
| 2 | 0 | 2 | 7 | 27 | 53 | 11 |
| 3 | 0 | 2 | 7 | 28 | 53 | 10 |
| 4 | 0 | 2 | 8 | 28 | 52 | 10 |
| 5 | 0 | 2 | 8 | 29 | 51 | 10 |
| 6 | 0 | 3 | 9 | 30 | 49 | 9 |
| 7 | 0 | 3 | 10 | 30 | 48 | 9 |
| 8 | 1 | 3 | 11 | 31 | 47 | 8 |
| 9 | 1 | 4 | 12 | 31 | 45 | 8 |
| 10 | 1 | 4 | 13 | 32 | 44 | 7 |
| 11 | 1 | 5 | 14 | 32 | 42 | 7 |
| 12 | 1 | 5 | 15 | 32 | 40 | 6 |
| 13 | 1 | 6 | 16 | 33 | 38 | 5 |
| 14 | 1 | 7 | 18 | 33 | 36 | 5 |
| 15 | 1 | 7 | 19 | 34 | 34 | 4 |
| 16 | 2 | 8 | 20 | 34 | 32 | 4 |
| 17 | 2 | 9 | 22 | 35 | 29 | 3 |
| 18 | 2 | 10 | 23 | 35 | 27 | 3 |
| 19 | 3 | 11 | 24 | 35 | 25 | 2 |
| 20 | 3 | 12 | 25 | 36 | 22 | 2 |
| 21 | 4 | 13 | 26 | 35 | 20 | 2 |
| 22 | 4 | 13 | 28 | 35 | 18 | 1 |
| 23 | 5 | 14 | 29 | 35 | 16 | 1 |
| 24 | 5 | 15 | 30 | 35 | 14 | 1 |
| 25 | 6 | 16 | 31 | 34 | 13 | 1 |
| 26 | 7 | 17 | 32 | 33 | 11 | 0 |
| 27 | 7 | 17 | 34 | 33 | 9 | 0 |
| 28 | 8 | 18 | 34 | 31 | 8 | 0 |
| 29 | 9 | 19 | 34 | 30 | 7 | 0 |
| 30 | 10 | 20 | 35 | 29 | 6 | 0 |
Wind in September
Winds average 10 km/h in September.
Across September, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 11 | 11 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| 1 | 10 | calm |
| 2 | 10 | calm |
| 3 | 10 | calm |
| 4 | 10 | calm |
| 5 | 10 | calm |
| 6 | 10 | calm |
| 7 | 10 | calm |
| 8 | 10 | calm |
| 9 | 10 | calm |
| 10 | 10 | calm |
| 11 | 10 | calm |
| 12 | 10 | calm |
| 13 | 10 | calm |
| 14 | 10 | calm |
| 15 | 10 | calm |
| 16 | 10 | calm |
| 17 | 10 | calm |
| 18 | 10 | calm |
| 19 | 10 | calm |
| 20 | 10 | calm |
| 21 | 10 | calm |
| 22 | 10 | calm |
| 23 | 10 | calm |
| 24 | 10 | calm |
| 25 | 10 | calm |
| 26 | 10 | calm |
| 27 | 10 | calm |
| 28 | 10 | calm |
| 29 | 11 | calm |
| 30 | 11 | calm |
Sunrise & sunset in September
Daylight runs from about 12 h 48 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.
Days shrink by about 66 minutes over September. Sunrise moves from 5:25 AM to 5:47 AM, and sunset from 6:11 PM to 5:29 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 12.8 | 12.7 | 12.7 | 12.7 | 12.6 | 12.6 | 12.5 | 12.5 | 12.5 | 12.4 | 12.4 | 12.4 | 12.3 | 12.3 | 12.3 | 12.2 | 12.2 | 12.1 | 12.1 | 12.1 | 12.0 | 12.0 | 12.0 | 11.9 | 11.9 | 11.8 | 11.8 | 11.8 | 11.7 | 11.7 |
| Sunrise (AM) | 5:25 | 5:26 | 5:27 | 5:28 | 5:28 | 5:29 | 5:30 | 5:31 | 5:31 | 5:32 | 5:33 | 5:34 | 5:34 | 5:35 | 5:36 | 5:37 | 5:37 | 5:38 | 5:39 | 5:39 | 5:40 | 5:41 | 5:42 | 5:42 | 5:43 | 5:44 | 5:45 | 5:46 | 5:46 | 5:47 |
| Sunset (PM) | 6:11 | 6:10 | 6:08 | 6:07 | 6:06 | 6:04 | 6:03 | 6:01 | 6:00 | 5:58 | 5:57 | 5:55 | 5:54 | 5:52 | 5:51 | 5:49 | 5:48 | 5:46 | 5:45 | 5:43 | 5:42 | 5:40 | 5:39 | 5:37 | 5:36 | 5:35 | 5:33 | 5:32 | 5:30 | 5:29 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 12.8 | 5:25 | 6:11 |
| 2 | 12.7 | 5:26 | 6:10 |
| 3 | 12.7 | 5:27 | 6:08 |
| 4 | 12.7 | 5:28 | 6:07 |
| 5 | 12.6 | 5:28 | 6:06 |
| 6 | 12.6 | 5:29 | 6:04 |
| 7 | 12.5 | 5:30 | 6:03 |
| 8 | 12.5 | 5:31 | 6:01 |
| 9 | 12.5 | 5:31 | 6:00 |
| 10 | 12.4 | 5:32 | 5:58 |
| 11 | 12.4 | 5:33 | 5:57 |
| 12 | 12.4 | 5:34 | 5:55 |
| 13 | 12.3 | 5:34 | 5:54 |
| 14 | 12.3 | 5:35 | 5:52 |
| 15 | 12.3 | 5:36 | 5:51 |
| 16 | 12.2 | 5:37 | 5:49 |
| 17 | 12.2 | 5:37 | 5:48 |
| 18 | 12.1 | 5:38 | 5:46 |
| 19 | 12.1 | 5:39 | 5:45 |
| 20 | 12.1 | 5:39 | 5:43 |
| 21 | 12.0 | 5:40 | 5:42 |
| 22 | 12.0 | 5:41 | 5:40 |
| 23 | 12.0 | 5:42 | 5:39 |
| 24 | 11.9 | 5:42 | 5:37 |
| 25 | 11.9 | 5:43 | 5:36 |
| 26 | 11.8 | 5:44 | 5:35 |
| 27 | 11.8 | 5:45 | 5:33 |
| 28 | 11.8 | 5:46 | 5:32 |
| 29 | 11.7 | 5:46 | 5:30 |
| 30 | 11.7 | 5:47 | 5:29 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 4.09 kWh/m².
For context, solar energy here swings from a low near 2.63 kWh/m² to a high of 5.38 kWh/m² in May across the year — September's 4.09 kWh/m² falls in the middle.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 4.7 | 4.6 | 4.6 | 4.5 | 4.5 | 4.5 | 4.4 | 4.4 | 4.3 | 4.3 | 4.3 | 4.2 | 4.2 | 4.1 | 4.1 | 4.1 | 4.0 | 4.0 | 4.0 | 3.9 | 3.9 | 3.9 | 3.8 | 3.8 | 3.8 | 3.7 | 3.7 | 3.7 | 3.6 | 3.6 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 4.7 | Bright |
| 2 | 4.6 | Bright |
| 3 | 4.6 | Bright |
| 4 | 4.5 | Bright |
| 5 | 4.5 | Bright |
| 6 | 4.5 | Bright |
| 7 | 4.4 | Bright |
| 8 | 4.4 | Bright |
| 9 | 4.3 | Bright |
| 10 | 4.3 | Bright |
| 11 | 4.3 | Bright |
| 12 | 4.2 | Bright |
| 13 | 4.2 | Bright |
| 14 | 4.1 | Bright |
| 15 | 4.1 | Bright |
| 16 | 4.1 | Bright |
| 17 | 4.0 | Bright |
| 18 | 4.0 | Moderate |
| 19 | 4.0 | Moderate |
| 20 | 3.9 | Moderate |
| 21 | 3.9 | Moderate |
| 22 | 3.9 | Moderate |
| 23 | 3.8 | Moderate |
| 24 | 3.8 | Moderate |
| 25 | 3.8 | Moderate |
| 26 | 3.7 | Moderate |
| 27 | 3.7 | Moderate |
| 28 | 3.7 | Moderate |
| 29 | 3.6 | Moderate |
| 30 | 3.6 | Moderate |
Hazard calendar for Iwata
In September, Iwata sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Iwata sits in the Pacific typhoon belt; the season peaks July–October.
Is September a good time to visit Iwata?
Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
September is a reasonable time to visit Iwata for sightseeing.
What to pack for Iwata in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Iwata sees daytime highs around 28°C and nights near 22°C. Pack light clothes and rain gear. About 16 days see rain.
Sea temperature near Iwata in September
The nearest coast averages about 26°C in September — 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 27°C and coldest in February near 16°C.
It's comfortable for a long swim from May 25 to Nov 29 — about 6.2 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 16 | 16 | 16 | 17 | 19 | 22 | 25 | 27 | 26 | 23 | 21 | 19 |
| Comfort | Cool | Cool | Cool | Cool | Cool | Refreshing | Warm | Warm | Warm | Refreshing | Refreshing | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 16 | Cool |
| Feb | 16 | Cool |
| Mar | 16 | Cool |
| Apr | 17 | Cool |
| May | 19 | Cool |
| Jun | 22 | Refreshing |
| Jul | 25 | Warm |
| Aug | 27 | Warm |
| Sep | 26 | Warm |
| Oct | 23 | Refreshing |
| Nov | 21 | Refreshing |
| Dec | 19 | Cool |
UV index in Iwata in September
Clear-sky midday UV in September peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Iwata peaks around July 20 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 3 | 4 | 5 | 7 | 9 | 10 | 10 | 10 | 9 | 6 | 4 | 3 |
| Level | Moderate | Moderate | Moderate | High | Very high | Very high | Extreme | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 4 | Moderate |
| Mar | 5 | Moderate |
| Apr | 7 | High |
| May | 9 | Very high |
| Jun | 10 | Very high |
| Jul | 10 | Extreme |
| Aug | 10 | Very high |
| Sep | 9 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 3 | Moderate |
Air quality in Iwata in September
Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.
Air quality in Iwata is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 9 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 11 | 14 | 19 | 21 | 19 | 16 | 12 | 11 | 10 | 11 | 10 | 9 |
| Level | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 11 | Good |
| Feb | 14 | Moderate |
| Mar | 19 | Moderate |
| Apr | 21 | Moderate |
| May | 19 | Moderate |
| Jun | 16 | Moderate |
| Jul | 12 | Good |
| Aug | 11 | Good |
| Sep | 10 | Good |
| Oct | 11 | Good |
| Nov | 10 | Good |
| Dec | 9 | Good |
Where is Iwata?
Iwata sits at 34.7°N, 137.8°E, 5 m above sea level, in Japan. The nearest listed city is Fukuroi, 8.0 km away.
Topography around Iwata
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Iwata.
Within 3 km, the terrain around Iwata has only modest variations in elevation — a maximum elevation change of 36 m around an average of 6 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 262 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,576 m.
The land around Iwata is covered by artificial surfaces (53%) and cropland (37%) within 3 km, water (35%) and artificial surfaces (31%) within 16 km, and trees (45%) and water (44%) within 80 km.
Japan travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B
- 100 V · 50 / 60 Hz
- Prices
- ≈ 65% of US
- price level, 2025
- GDP per capita
- $35,951
- 2025
- Happiness
- 6.1 / 10
- World Happiness, 2025
- Safe drinking water
- 99%
- of population, 2024
- Homicide rate
- 0.2
- per 100k, 2023
- Road deaths
- 3.6
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Very low
- EF EPI 446
- 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 Iwata (34.7°, 137.85°, elevation 5 m), 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).