Honshu, map

In Mito, a Japanese city in the Ibaraki prefecture, one hour by train (Limited Express or tokkyu) from Tokyo, the climate is temperate, with quite cold but sunny winters, and hot, humid and rainy summers. Like the rest of Japan, the city is affected by the monsoon circulation: in winter the northwest cold currents will prevail, while in summer they will be replaced by hot and humid currents of tropical origin.
The city is in a relatively favorable position: given the relatively low latitude (we are on the 36th parallel) and the protection of the mountains (we are on the east side), in winter the currents of Siberian origin are felt little, so there are many sunny days, and usually it's not very cold during the day (although at night the temperature often drops below freezing), however, cold and windy periods, with highs around 5/7 °C (41/45 °F) or less, are possible. Snowfalls are usually light; on average, 18 centimeters (7 inches) of snow fall per year. The temperature rarely drops below -6 °C (21 °F), however, in 1963 and in 1984 it dropped to -11 °C (12 °F).
In summer, there are hot and muggy periods (though less intense than in Tokyo) but also periods of bad weather, windy and rainy, and sometimes (especially in June and July) a little cool, due to the northeast wind, called Yamase. August is the hottest month because of the thermal inertia of the sea.
Here are the average temperatures.
Mito - Average temperatures
Min (°C)-2-22712162022181250
Max (°C)9912182124283026211611
Min (°F)282836455461687264544132
Max (°F)484854647075828679706152

Precipitation is quite abundant (even though it does not rain as much as in other areas of Japan), in fact it amounts to 1,350 millimeters (53 inches) per year; winter is the driest season, while the rainiest months are September and October, also because of the contribution given by typhoons. In fact, from June to October (but especially from August to early October), Mito can be affected by typhoons.
Here is the average precipitation.
Mito - Average precipitation

The cherry blossoming in Mito occurs in early April.
The main tourist attraction of Mito is the Kairaku-en, the Japanese garden, considered one of the three most important, along with Kenroku-en in Kanazawa and Koraku-en in Okayama. Since it houses a plum forest, an interesting time to visit is that of the blossoming of plum trees, which normally occurs in late February and in March, when also the Mito Plum Festival (Mito Ume Matsuri) is held.

Kairakuen Garden

The sea in Mito, cold in winter, becomes acceptable for swimming in August and September, while in July it is still a bit cool, as you can see in the following table.
Mito - Sea temperature
Temp (°C)141212151719222423201714
Temp (°F)575454596366727573686357

The amount of sunshine in Mito is good in winter (in January there are no less than 6 hours of sunshine per day), while it is just mediocre or decent in the other seasons because of both the disturbances that occur in spring and autumn and of the summer monsoon. In summer, there are only 4 hours of sunshine per day in June and July, and 5 and a half in August.
Mito - Sunshine