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Would that it were that simple.
Static cold temperature is really irrelevant because as you drive the tyres heat up and the pressure increases, so what you actually need to do is drive for 30 minutes as you would expect to drive for the rest of the journey then set the hot pressures.
This doesn’t work, though, if the first 30 minutes are pottering through town and the next bit is attacking B roads or speedy motorway work as the temperature difference and therefore pressure difference will be huge. So really you need to do a practice journey, check and set the pressures as you go, write them down, work out the mean and set them to that.
Getting the car up into our 1st floor flat is a bit tricky to make sure it's at room temperature.
Or, just apply a bit of SCIENCE.
https://www.continental-tires.com/car/tire-knowledge/winter-world/tire-pressure-in-winter
According to that: 10 degrees C is worth 1-2 PSI (0.07 to 0.14 bar).
So if it's ~5 deg C outside then just inflate them to ~3 PSI lower than recommended.