Reduced Speed Ahead Signs warn motorists of upcoming speed limit reductions. These signs are used when engineering judgment deems them necessary for compliance with the reduced speed limit. Some factors taken into consideration when deciding if Reduced Speed Ahead Signs are needed include how far in advance speed limit signs can be seen and how much the speed is being reduced.
As you may have noticed, the signs above look different from the black and white rectangular signs that were used previously. That is because the speed reduction signs have been changed to warning signs rather than regulatory signs, and therefore the sign designs have also been changed.