Nevada is somewhat ambiguous on frost and thaw travel restrictions. One reference suggests "Frost Laws" are in effect from February 1 through (about) April 30. Nevada provides a map (frost law map), but it is lacking details or any substantive guidance.
Nevada's online DOT site is less than informative on this topic.
Shipment Routes: http://www.state.nv.us/nucwaste/trans/pic3/3pic06.htmCalculate Oversize/Overweight Load Regulations and Prices Instantly with Oversize.io