A large difference between daytime and nighttime temperatures is common to the area at this time of year. The nighttime temperatures usually seem to range from mid 30s to the 50s, e.g. chilly. This can lead to another problem encountered at the War, hypothermia. This is a drop of the core temperature of the body, which can lead to coma and death if not treated. Treatment is to warm the person up as quickly as possible.
It is easier to avoid hypothermia by changing out of wet clothes, drying off, and getting warm. If a friend is wet (say after being out in the rain) and getting cold (since the temperature dropped 30 degrees in the last hour) help them out. Get them into dry clothes and get them warm. Strong drink (liquor) is not advised if they are still wet or cold. While they may seem to feel warmer, drinking alcohol speeds heat loss, which is what you are trying to avoid.