Biwa shouldn't be to different then Kyoto weather wise (Biwa is only about 70km NE) and always just had a nip in the air (which was desired since it will still be in the mid to high 30s in TH)
Originally Posted by
Pseudo Nim
As long as you're in the lowlands, which I think Biwa is, you should be fine (Yamanakako is quite high up in the mountains, so it's significantly colder there, resulting in late blooms).