Temporal Storm - only drifters spawned?

[RationallyParanoid]

Exactly what it says on the tin, folks!

I recently went through my first medium temporal storm in my new forever world, and only drifters spawned.
The previous storms graced me with drifters, bowtorn and shivers (absolute banger parties they were).
Is this a rare occurrence in game? I'm on v 1.21.5

I do play with mods, but the only thing that affects spawns is that I have Bells turned off (hate the blasted things and the noise they make).

[MKMoose]

This is expected during 10% of the storms.

From assets/survival/config/mobextraspawns.json, a pattern is chosen randomly by weight to determine the maximum quantities of each type of monster that are allowed to spawn:

spawnPatterns: {
	"default": { weight: 5, groupWeights: { drifter: 0.5, shiver: 0.25, bowtorn: 0.25 } },
	"drifterstorm": { weight: 1, groupWeights: { drifter: 1, shiver: 0, bowtorn: 0 } },
	"shiverstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0.6, bowtorn: 0 } },
	"bowtornstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0, bowtorn: 0.6 } },
	"shiverbowtornstorm": { weight: 1, groupWeights: { drifter: 0.25, shiver: 0.375, bowtorn: 0.375 } },
	"driftershiverstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0.6, bowtorn: 0 } },
}

[RationallyParanoid]

6 minutes ago, MKMoose said:

This is expected during 10% of the storms.

From assets/survival/config/mobextraspawns.json, a pattern is chosen randomly by weight to determine the maximum quantities of each type of monster that are allowed to spawn:

spawnPatterns: {
	"default": { weight: 5, groupWeights: { drifter: 0.5, shiver: 0.25, bowtorn: 0.25 } },
	"drifterstorm": { weight: 1, groupWeights: { drifter: 1, shiver: 0, bowtorn: 0 } },
	"shiverstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0.6, bowtorn: 0 } },
	"bowtornstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0, bowtorn: 0.6 } },
	"shiverbowtornstorm": { weight: 1, groupWeights: { drifter: 0.25, shiver: 0.375, bowtorn: 0.375 } },
	"driftershiverstorm": { weight: 1, groupWeights: { drifter: 0.4, shiver: 0.6, bowtorn: 0 } },
}

Aha! Thanks for the quick response 
Good to know I won't have to go sorting through my mods list