Is the size of the double arrow sign (W1-7) changing?
In short, no.
Some folks have recently heard the double arrow sign is going to be a different size. The National MUTCD, the NYS Supplement, and the National Standard Highway Signs and Markings books show the standard size is still 48” x 24”.
If you wanted to put up a larger sign due to visibility or other safety concerns, the size would be 60” x 30”, still a ratio of 2:1 in width to height.
Resources
Cornell Local Roads Program MUTCD page
(shows how to order both documents that make up the MUTCD in New York State)
Standard Highway Signs and Markings
FHWA
