Primness and the diurnal cycle are clearly linked. The amount of light hitting the retina, or lack thereof, which ever way you prefer to think of things, acts as the physiological trigger to the pituitary gland :the master regulatory gland of the endocrine (hormonal) system. Primness occurs when the blood flow to the hair follicles subsides; the hair growth phase begins to end or stops completely; the inside of the hide looses its blue color as the rate of hair growth lessens and finally stops.
In colder climes the amount of sunlight is greatly reduced thatís one reason itís colder. This aspect of climate is the selective pressure that provides, via the forces of evolution, for heavier furred animals in these regions. In addition, the general nutritional status of the individual animal or population, will impact greatly on the quality of fur in a given year, region or set of circumstances. We often speak of this in terms of the energy balance; in years of adequate too plenty of food stuffs, the animals will have a higher energy balance, be healthier, have bigger litters which will have higher survival rates, grow faster and have the best fur possible based on their genetic make up. In poor years things are reversed and the general observation will be lower quality in fur and fewer animals. During transition years you get something in between.
Within a clime you will have a variety of factors, besides food stuffs that can affect the fur quality. Lots of snow can lead to earlier rubbing do to increased guard hair loss in the beds. Higher than normal temperature can lead to discomfort for heavily furred animals which will in turn show a tendency to an increase in mechanical damage to the fur and lower quality.
Hope this helps some.