晴れた日にはピクニックに行くほど楽しいことはない。

to clear up; to clear away; to be sunny; to stop raining; to refresh (e.g. spirits); to be cleared (e.g. of a suspicion); to be dispelled; to be banished

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

picnic

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

to go; to move (in a direction or towards a specific location); to head (towards); to be transported (towards); to reach; to proceed; to take place; to pass through; to come and go; to walk; to die; to pass away; to do (in a specific way); to stream; to flow; to continue; to have an orgasm; to come; to cum; to trip; to get high; to have a drug-induced hallucination

degree; extent; bounds; limit; indicates approx. amount or maximum; upper limit

enjoyable; fun

thing; matter; incident; occurrence; event; something serious; trouble; crisis; circumstances; situation; state of affairs; work; business; affair; after an inflectable word, creates a noun phrase indicating something the speaker does not feel close to; nominalizing suffix; pretending to ...; playing make-believe ...; alias; aka; nickname; alternative name; also known as

not; emphatic suffix