Autocross tires + storing in cold weather

So I know your supposed to keep autocross tires above freezing but over this winter we had a set in a heated shop and one night the shop breaker popped and the shop got cold enough to freeze inside. Im guessing right around the -15 degrees celcius mark, outside was -42 degrees but Im hoping it held heat decently but it did manage to freeze all the water jugs I had in the shop.

Curious what actually is the danger for this?are these tires now throw aways or just maybe not quite as grippy as they wouldve been? The tires were brought back up to zero slowly and during this whole thing the car wasnt moved. I dont see any cracking or damage on them. Tires are Toyo RTR's

They certainly aren't throw away now, but they likely will be a bit off the pace of fresh and unfrozen.  I.E. good for locals and whatnot but if you are in a chase for a trophy at Lincoln you might want another set by then.

What happens to the trucks of tires driving through Minnesota to the tires rack warehouse in Saint Paul. All those new tires must be trash now. 

I'd love to see a lab test that shows if theres any measurable grip lose between tires summers kept at "ideal" temps vs those uncovered in a garage all winter.

I was always thought it was the UVs that did all the damage not necessarily storage temps.

Fueled by Caffeine said:

What happens to the trucks of tires driving through Minnesota to the tires rack warehouse in Saint Paul. All those new tires must be trash now. 

The key is if they are cold shocked after they have been scrubbed. If they are, most likely they are permanently damaged at the molecular level. But prior to the first scrub and a proper heat cycling they should be more resilient. 

KyAllroad (Jeremy) said:

They certainly aren't throw away now, but they likely will be a bit off the pace of fresh and unfrozen.  I.E. good for locals and whatnot but if you are in a chase for a trophy at Lincoln you might want another set by then.

If he's in a chase for a trophy at Nationals he probably wants to have tires made with technology from this decade so a new set is in order anyway in that case. One day of being cold, not driven on, and slowly brought back up to temp should have no real impact on them.

Thanks, Yeah Im not too worried about them being as grippy as possible. Mostly just want to make sure its okay to run on them or am I going to be risking tire seperation

For a track trials type event last year I put a brand new set of A7s on the Exocet and did two short HPDE sessions in the morning to get the tires ready for afternoon timed runs.  Ran three solid timed runs and it started to rain.  Thought I was done for the day and put the practice set of two year old Hoosiers back on the car.  They had been through two winters in the garage just stacked in the corner.  The weather cleared and I got another two runs in on the old tires and took a second off the new A7 times. 

I think the falloff on old tires is more due to heat cycling than freezing.  Exocets don't weight much and so don't get the tires very hot so tires seem to last forever.

I always had my re71rs just stored away in the garage during winter.  They survived 2 winters with being beat on in the summer.  Ran them until about bald, they always seemed to be ok.