Meaning : In keeping with the season.
Example :
A hard but seasonable frost.
Seasonable clothes.
Not in keeping with (and usually undesirable for) the season.
A sudden unseasonable blizzard.Meaning : Done or happening at the appropriate or proper time.
Example :
A timely warning.
With timely treatment the patient has a good chance of recovery.
A seasonable time for discussion.
The book's publication was well timed.
Synonyms : timely, well timed, well-timed