Best time to visit Koshigaya
Month-by-month weather averages for Koshigaya.
Koshigaya, Saitama, Japan
°C
mm
- Average daily high and low
- Precipitation
- Good month
- Best month
- Made good or best by an event
| Month | Average daily high | Average daily low | Precipitation | Verdict |
|---|---|---|---|---|
| January | 9.5 °C / 49 °F | -0.2 °C / 32 °F | 46 mm / 1.8 in | neither best nor good |
| February | 10.5 °C / 51 °F | 0.9 °C / 34 °F | 62 mm / 2.5 in | neither best nor good |
| March | 14.5 °C / 58 °F | 4.6 °C / 40 °F | 100 mm / 3.9 in | good month |
| April | 19.1 °C / 66 °F | 9.6 °C / 49 °F | 119 mm / 4.7 in | good month |
| May | 23.9 °C / 75 °F | 15 °C / 59 °F | 130 mm / 5.1 in | good month |
| June | 26.6 °C / 80 °F | 19.3 °C / 67 °F | 148 mm / 5.8 in | good month |
| July | 30.5 °C / 87 °F | 23.6 °C / 74 °F | 160 mm / 6.3 in | neither best nor good |
| August | 32.2 °C / 90 °F | 24.9 °C / 77 °F | 112 mm / 4.4 in | neither best nor good |
| September | 27.9 °C / 82 °F | 21.1 °C / 70 °F | 165 mm / 6.5 in | neither best nor good |
| October | 22.1 °C / 72 °F | 14.7 °C / 58 °F | 180 mm / 7.1 in | good month |
| November | 16.9 °C / 62 °F | 8.1 °C / 47 °F | 83 mm / 3.3 in | good month |
| December | 11.8 °C / 53 °F | 2.3 °C / 36 °F | 61 mm / 2.4 in | good month |
Good and best months depend on more than temperature, rain and events. How they are chosen
Each activity on this page has its own good and best months, rated on twenty years of daily weather records. Which measures count, and how much, depends on the activity: humidity for exploring outdoors, wind for the beach, hiking and skiing, snow for skiing alone. Between them, the activities are rated on:
- Daytime highs
- Night-time lows
- How warm it feels
- Humidity
- How much of the day is sunny
- Hours of daylight
- Monthly rainfall
- How many days it rains
- Days of heavy rain
- Wind
- Snowfall and days with snow
- Major events, such as festivals
The chart shows the good and best months for exploring outdoors.
The event icon marks a month that an event lifts to good or best, such as a festival or a natural spectacle. Choose “Weather only” in the toolbar to rate the months on weather alone.
Best months by activity
Exploring outdoors
Mild days and nights, mostly dry and bright. The default for 'when should I go'.
- JJanuary: neither
- FFebruary: neither
- MMarch: good
- AApril: good
- MMay: good
- JJune: good
- JJuly: neither
- AAugust: neither
- SSeptember: neither
- OOctober: good
- NNovember: good
- DDecember: good
- Good
- March–June, October–December
Why these months
March · good
In its favour: share of daylight that is sunny 71%, precipitation 100 mm / 3.9 in, average daily high 14.5 °C / 58 °F, relative humidity 63%, days with heavy rain 3.5 days, wet days 10.3 days, average daily low 4.6 °C / 40 °F.
Against: feels like (high) 11.4 °C / 53 °F.
April · good
In its favour: feels like (high) 17.2 °C / 63 °F, average daily high 19.1 °C / 66 °F, share of daylight that is sunny 67%, precipitation 119 mm / 4.7 in, average daily low 9.6 °C / 49 °F, relative humidity 66%, days with heavy rain 3.8 days, wet days 11.7 days.
May · good
In its favour: feels like (high) 23.8 °C / 75 °F, average daily high 23.9 °C / 75 °F, share of daylight that is sunny 63%, average daily low 15 °C / 59 °F, precipitation 130 mm / 5.1 in, relative humidity 69%, wet days 11.6 days, days with heavy rain 4.5 days.
June · good
In its favour: feels like (high) 28.6 °C / 83 °F, share of daylight that is sunny 54%, average daily high 26.6 °C / 80 °F, average daily low 19.3 °C / 67 °F, relative humidity 76%.
Against: precipitation 148 mm / 5.8 in, wet days 13.4 days, days with heavy rain 4.8 days.
October · good
In its favour: feels like (high) 22.2 °C / 72 °F, average daily high 22.1 °C / 72 °F, share of daylight that is sunny 62%, average daily low 14.7 °C / 58 °F, relative humidity 75%.
Against: precipitation 180 mm / 7.1 in, wet days 12.5 days, days with heavy rain 4.8 days.
November · good
In its favour: feels like (high) 15.2 °C / 59 °F, share of daylight that is sunny 70%, average daily high 16.9 °C / 62 °F, precipitation 83 mm / 3.3 in, days with heavy rain 2.5 days, wet days 9.3 days, average daily low 8.1 °C / 47 °F, relative humidity 71%.
December · good
In its favour: precipitation 61 mm / 2.4 in, share of daylight that is sunny 78%, wet days 6.6 days, days with heavy rain 1.9 days, relative humidity 66%.
Against: feels like (high) 8.6 °C / 47 °F, average daily high 11.8 °C / 53 °F, average daily low 2.3 °C / 36 °F.
An activity is listed only where it applies: skiing at ski destinations, beach and swimming at beach destinations. The nearest ski area is 丸沼高原スキー場, Marunuma Kogen Ski Resort, 109 km away.
Weather averages
Monthly averages over twenty years, 2006–2025. Highs, lows and precipitation are in the chart at the top.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels like (high) | 5.3 °C | 6.5 °C | 11.4 °C | 17.2 °C | 23.8 °C | 28.6 °C | 34.7 °C | 36.8 °C | 30.7 °C | 22.2 °C | 15.2 °C | 8.6 °C |
| Days with heavy rain | 1.4 days | 1.9 days | 3.5 days | 3.8 days | 4.5 days | 4.8 days | 5.3 days | 2.9 days | 5.2 days | 4.8 days | 2.5 days | 1.9 days |
| Time rain usually falls | 4 pm | 10 am | 11 am | 11 pm | 6 am | 8 am | 3 pm | 3 pm | 3 am | 5 am | 6 am | 8 am |
| Sunshine per day | 8.4 h | 8.3 h | 8.5 h | 8.8 h | 8.8 h | 7.9 h | 8.3 h | 9.7 h | 7.8 h | 7 h | 7.2 h | 7.6 h |
| Relative humidity | 61% | 61% | 63% | 66% | 69% | 76% | 78% | 75% | 77% | 75% | 71% | 66% |
Air quality
Averaged over a shorter period (2022–2025) than the twenty-year averages above, and not counted towards good or best months.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Air pollution (PM2.5) 2022–2025 | 17.1 µg/m³ | 14.3 µg/m³ | 19.7 µg/m³ | 22.3 µg/m³ | 20.8 µg/m³ | 26.7 µg/m³ | 30 µg/m³ | 19.1 µg/m³ | 17.7 µg/m³ | 17 µg/m³ | 21.5 µg/m³ | 19.5 µg/m³ |
| Air pollution (PM2.5, daily peak) 2022–2025 | 38.7 µg/m³ | 31 µg/m³ | 36.6 µg/m³ | 39.3 µg/m³ | 35.1 µg/m³ | 43.3 µg/m³ | 48.8 µg/m³ | 31.5 µg/m³ | 31 µg/m³ | 33.5 µg/m³ | 45.2 µg/m³ | 45.5 µg/m³ |
- Good 15 µg/m³ or less
- Fair 15 to 25 µg/m³
- Moderate 25 to 37.5 µg/m³
- Poor 37.5 to 50 µg/m³
- Very poor 50 to 75 µg/m³
- Extremely poor over 75 µg/m³
Each figure is compared with the World Health Organization's guideline for a day's air, 15 µg/m³ or less, and with its interim targets above that. The words are ours: the WHO does not name its steps. The figures are modelled monthly averages, so single days can be well above them. The daily peak is the average of each day's highest hour, shaded on the same scale.