I've found that a
PolarBottle will buy you a little more time than a standard, non-insulated bottle. I did a little experiment last December...
Temperature units are degrees Fahrenheit.
Code:
Elapsed Water Temp Outdoor
Time Polar | Generic Temp
---------------------------------------
0:00 106 106 5.2
0:40 79 61 6.0
1:25 59 33 6.8 Ice forming on top of generic bottle
2:10 39 31 7.7 Top/Sides of generic bottle frozen