Is the weather condition a factor to consider when choosing a driving speed?

In the photo you are driving along a winding road through a forest, with a double solid line on the bend. The question is whether the weather conditions are a factor which you take into account when choosing your speed. Yes, always - answer C.

The Road Traffic Act states that a driver is obliged to drive at a speed which ensures control over the vehicle, taking into account the conditions in which traffic takes place, in particular: the shape of the terrain, the condition and visibility of the road, the condition and load of the vehicle, the weather conditions and the traffic volume. The weather conditions are listed directly, without any extra condition - that is why answer B, which makes this depend on heavy traffic, is wrong, and answer A simply contradicts the Act. Rain makes the braking distance longer and brings a risk of skidding on a layer of water, fog reduces visibility, snow and ice can make braking several times longer, and a strong crosswind pushes the car out of its lane. In such conditions you drive more slowly than the sign allows and increase your following distance from the vehicle in front; exceeding the "safe speed" is a petty offence even when you are not exceeding the speed limit.

Legal basis: Art. 19 para. 1 of the Road Traffic Act (Prawo o ruchu drogowym)