I was travelling south on highway 14 with my family after visiting Devil’s Tower. 4/10 of a mile before the intersecion with I-90, we passed a sign saying that the speed was going to be reduced to 45mph (from 65) in 750 Fort Then we passed the 45 mph sign. 2/10 mile after I-90 we passed a second sign indicating the speed limit to be 45mph. 3/10 mile later another signed posted the speed at 45mph. 2/10 mile later, a sign indicated the speed is 30mph. There was no warning about the upcoming reduced speed. To emphasize, the 30mph change was the final of 5 signs within a 1 mile stretch of road with the other 4 indicating 45mph. Needless to say, I was going about 45mph when I passed this sign. 1/10 mile after the 30mph sign, an officer clocks our speed at 47mph, flashes his lights, and we pull over where he issues a traffic citation. A court date 9 business days in the future is given me when my I will need to be present or I can pay the fine by mail. I will be on vacation until 4 business days before the set date-this apparently has no bearing on the date. However, the officer is kind enough to provide a pre addressed envelope for my use in paying the fine by mail. As far as I am concerned, I was going the speed limit unless I am supposed to predict upcoming changes. In this case, I would have had to know the speed was going to drop 15mph less than 2/10 of a mile after seeing 3 signs posting 45mph as the limit. Is this legal? I am going to contest this citation. By the way, this was the only place on our trip of 3500 miles across Washington, Montana, Wyoming, and South Dakota where there was no posted warning about an upcoming speed reduction.