Freeze Point
"The freezing point of jet fuel is defined as the temperature at which the last crystal melts when warming a fuel that has been previously cooled until hydrocarbon crystals form".
It's been a while, but the majority of JetA1/ Avtur batches I tested had a freeze point in the -57 to -60 degrees C range (Australia). Can't recall seeing one in the minus 40's..
Octane