He was on his way to a meeting in Pembrokeshire when he noticed the woman dangerously close to traffic.
Coleman is said to have driven around Haverfordwest for half an hour to see if the woman could recognise her home, before calling friends in the town to ask for help.
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Rain overnight turning light and patchy in the morning.
Most of us will have a pleasant and dry evening with a few late sunny spells, though the odd light shower is possible.
The Eisteddfod's intention to visit an area must be proclaimed at least a year and a day before the beginning of the festival.