Caiff y terfynau cyflymder dros dro o 50 milltir yr awr eu cyflwyno ar ddarnau bach o ffyrdd, sef rhwng 1.4km a 5.9km, yn y pum lleoliad canlynol:
The temporary 50 mph speed limits will be introduced at short stretches of road, between 1.4km to 5.9km in length, at the following five locations: