The Met Office says East Anglia is at greater risk of disruption from snow and ice on Thursday in its latest yellow weather warning
There is a separate weather warning in place for Friday.
The Met Office says: "There is a chance of snow settling with disruption to road, rail and air services as well as interruptions to power supplies and other utilities - this more likely across East Anglia and southeast England."
A polar maritime airmass, with its origins over northern Canada, moves into northern Scotland on Wednesday and then south across the whole of the UK during Thursday.
- Yellow weather warning in force from 10am until 11.55pm on Thursday 12 January
The Met Office weather computer forecast model animation below suggests some of Thursday's rain may turn to snow for a time in the south of the Anglia region late in the day which may coincide with the evening rush hour.
The Met Office says rain moving eastwards across the south of the UK on Thursday may turn to snow in places.
Associated heavy rain and strong winds may prove additional hazards. As skies clear on Thursday night there is also potential for widespread ice to form quite rapidly on untreated surfaces.
- Yellow weather warning in force from 0.05 am until 11.55 pm on Friday 13 January
A further weather warning for the risk of snow has been issued for Friday as a cold northerly air stream sets in.
The Met Office warning says: "Further showers of snow, sleet and hail will continue across parts of the UK. 2 to 4 cm of snow may affect some lowland areas, while high ground may see locally 5 to 10 cm."
The Met Office added that disruption to transport networks seems likely either due to snow or ice.
Additionally, northwesterly gales and large waves will affect some eastern coastal areas, perhaps leading to local over-topping.