Weather requirements are typically equivalent to local plant-mixed asphalt requirements
Ambient Temp 45°F (7°C) and rising
Not during rain or impending rain
Recent rainfall can impact HIR due to the additional energy required to remove excess moisture
If an unrolled HIR mix is caught in a heavy rainstorm, it can be compacted to support temporary traffic. However, the mat will probably not achieve the proper density. The mat can be reworked and compacted when dry conditions allow.