Background: I am managing a Project where I am responsible planning the construction of a visitor center on the peak of a mountain.
The Problem: During reading the brief, I have came across the following statement: "Poor weather conditions often make the peak inaccessible from November to March each year."
The Question: How would I adjust for the period between November to March? The statement above states "often," which I believe implies that some days between November to March will be accessible. However, how would I go about this? Do I simply assume the number of days which will be available for work by calculating number of days from November to March and finding the average?