That movie endless summer has it backwards. Surfing almost everywhere is better in the winter. It's just that winter in Hawaii is pretty warm.
Where I live we surf in the great lakes in late winter, starting about now actually till end of April.
While you're in the water with a wetsuit, it's not too bad. Water can't get too far below 0ºC but the air temperatures are often way below freezing, and the windchill can be brutal, because lake surfing is dependent on wind.
Getting out of my 5mm wet-suit in a parking lot in February taught me what it really means to be cold.
Since then, conditions I would have thought of as cold are much more tolerable.
Now if I have to take out the trash in the winter and there's fresh clean snow on the ground, instead of wrestling with winter boots I just go barefoot.
The secret to not feeling cold is that when you're cold, just let yourself be cold through and through. Don't fight it.