Saitama is warmest in August, averaging 31° by day and 22° at night. The wettest month is June with 240 mm, and the year brings about 1605 mm in total.
Month by month
| Month | High | Low | Rain | Sea | Daylight | Good for |
|---|---|---|---|---|---|---|
| January | 8° | -3° | 43 mm | 15° | 9.8 h | Cool |
| February | 9° | -2° | 48 mm | 14° | 10.7 h | Cool |
| March | 14° | 1° | 118 mm | 14° | 11.7 h | Mild |
| April | 19° | 5° | 129 mm | 15° | 12.9 h | Mild |
| May | 23° | 12° | 152 mm | 18° | 13.9 h | Mild |
| June | 27° | 16° | 240 mm | 22° | 14.4 h | Rainy season |
| July | 30° | 21° | 220 mm | 25° | 14.2 h | Rainy season |
| August | 31° | 22° | 205 mm | 27° | 13.4 h | Rainy season |
| September | 28° | 18° | 198 mm | 26° | 12.2 h | Rainy season |
| October | 21° | 11° | 155 mm | 23° | 11.1 h | Mild |
| November | 17° | 5° | 66 mm | 19° | 10.1 h | Sightseeing |
| December | 10° | -1° | 31 mm | 17° | 9.6 h | Cool |
High and low are average daily maximum and minimum, rain is typical monthly total, sea is the average surface temperature, daylight is the hours between sunrise and sunset mid-month. Climate normals from NASA POWER and NOAA MUR — averages, not promises.
When to go
Beach weather: No month in Saitama combines swimming warmth with dry skies.
Walking the city: November — highs of 17–17° and no more than 66 mm of rain a month.
Wet season: June, July, August and September — up to 240 mm in a single month.