Weather plays an extremely important role in scrub seal operations. The ideal weather conditions for this treatment are:
Air and surface temperatures are above60oF (16oC) and rising for emulsified asphalts.
Humidity is 50 percent or lower
Little to no wind
No rain in the forecast
Effects of rain before emulsion has cured
Unsuitable conditions for scrub seal construction are:
Cool nights make it very tough for scrub seals to cure or gain strength. This is why there are usually seasonal limitations on scrub seal construction.
Strong wind can distort the fan pattern of the asphalt being sprayed which could lead to streaking and uneven distribution. An apron can be installed around the spray bar to minimize the effects of wind if necessary.
High humidity can lead to longer break times for emulsified asphalts.
Saturated roadways can lead to longer break times due to water still being in the roadway.
Rainfall could lead to asphalt running off the roadway which could lead to rock loss.