Winter and spring: thermal margin and rapid changes
Spring usually broadens the choice, but aspect and altitude still need comparison. A comfortable city forecast does not necessarily describe an exposed wall. Activities with a specific rule retain that rule over general advice, while any notice or restriction must be checked before confirmation and again close to departure.
To compare two dates, record forecast temperature, precipitation probability, wind, daylight and estimated total duration. Apply the same list to each alternative, including approach and descent. This avoids choosing from a pleasant maximum temperature alone and preserves margin if the group moves more slowly than expected.

