Icing is funny and unpredictable, and the weather information may not always be totally correct as things can change quite quickly.
I have encountered it in cloud just at and sometimes just below the "freezing level" and yet flown in cloud well above the forcast freezing level height and never got any.
The above was always in a multi engine with de-ice equipment.
You must plan to avoid icing unless your a/c is equipped to deal with it, even then I would always try to get out of the conditions ASAP.
In Northern Europe, two things really scare me in IMC conditions that is, ICE and HIGH GROUND, keep away from both
Stay safe
Tony