I found this damage interesting because
- There are high winds here (coastal area) but the frontal area of a sign seems pretty small
- I thought they would make signs out of more corrosion resistant materials
These are only a few of tens if not hundreds of downed signs in the area
https://www.road-signs.uk.com/post-calculator.shtml
Having a quick look into it, it’s clearly something that is calculated for but wind up North is clearly something else!