Accessibility to the work site could be an issue due to changing weather conditions. For example, a jobsite may be a complete inaccessible due to mud during the middle of the work day due to thawing of the ground. However, in the early morning, before the sun comes up and before traffic is encountered, it is possible that the jobsite might be easily accessible. Therefore, workers must be made aware of each situation and foresight given to early movement of materials and staff in and out of the jobsite. Also, it may be necessary to stockpile materials on the roof prior to roofing installation as conditions and accessibility to the jobsite at the time of completing the work may make the delivery of materials impossible.