The ideal temperature for applying water-based concrete stain is 70 degrees Fahrenheit. You can apply the stain in temperatures as low as 45 degrees, but lower temperatures can cause slower drying time. The temperature can be as high as 90 degrees for stain application, but higher temperatures can prevent the stain from penetrating the concrete well.
Acid-based concrete stain should be applied when the concrete temperature is between 59 and 70 degrees Fahrenheit. The staining process will experience similar issues to water-based stains if the temperature is too high or too low.
High humidity can slow the drying time for concrete stains significantly. Windy conditions can cause the stain to dry too quickly and not penetrate the concrete well. Make sure the concrete is thoroughly cleaned and dried before staining and allow the work to cure for 24 to 48 hours before sealing.