Hey there Vypr,
We recommend outside temperatures of 55-60*F at least when installing deadener to get full adhesion
The adhesive will still apply well below that but the butyl naturally becomes much more plyable and stickier when in warmer temperatures.
A quick solution on a colder day is to lay the open box of Mat out in the sun for an hour before installation, allowing it to warm up a great amount past ambient epecially with it being black in color.
That is, if there is sunlight //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif