def calculate_fog_probability(min_temperature, fog_temperature):
    """
    Calculate fog probability using Craddock & Pritchard method.
    Provide forecasted minimum temperature and calculate fog temperature.

    ≥ +1	        Widespread fog
    = 0.5	        Risk for fog at end of night
    = 0	            Fog patches around sunrise
    -0.5 to -1.5    Fog patches on favorable spots
    ≤ -2            No fog

    Source: http://www.skystef.be/calculator-fog.htm

    :param min_temperature: forecasted minimum temperature in celsius
    :type min_temperature: float
    :param fog_temperature: calculated fog temperature in celsius
    :type fog_temperature: float
    :return: fog probability on a scale of 1 to 5 where 5 has wide spread fog
    :rtype: int
    """
    difference = fog_temperature - min_temperature

    if difference >= 1:
        return 5
    elif .5 <= difference < 1:
        return 4
    elif -.5 <= difference < .5:
        return 3
    elif -1.5 < difference < -.5:
        return 2
    else:
        return 1