Apparently the city's humid subtropical climate is much like New York City's with humid and hot summers; and seriously cold and snowy winters. It starts to rain a lot in in July and August. Akita in winter sees about 148 inches of snow! The temperature breakdowns are as follows:
Spring (March - May): March is quite chilly, but as the cherries blossom and spring comes to an end in May, the temperatures rise to a pleasant 20 degrees Celsius.
Summer (June - August): Things remain pleasant for the first half of June, and then it begins to rain, things get humid and sticky, which is terrible with the temperature reaching 25 degrees Celsius. It get stickier and wetter into July and August when daily averages are about 30 degrees Celsius. Nights are about 10 degrees Celsius cooler though.
Autumn (September - November): September is welcome after the rains, especially the nights, but is October when the mercury falls hard, 18 degrees Celsius in the day, 10 degrees Celsius at night. November is straight up chilly at night at 4 degrees Celsius.
Winter (December - February): Nights are almost always below 0, and the days rarely get warmer than 4 degrees Celsius. Add wind chill factors and things are quite terrible.
The best season to visit, despite the heat and high prices, is summer, when the city is basically exploding with reasons to have festivals. If its scenic beauty you want, and cheaper prices, families would be better off visiting in spring, when they should head out into the countryside.