A large number or amount of something that happens at the same time.
Spates can be good or bad, depending on what is happening.
Examples:
There were spates of rain all day long.
She had spates of good luck last week.
Spates of birds flew over our heads.
He had spates of sneezing during the allergy season.
There were spates of laughter at the funny movie.
Spates of snow covered the ground in winter.