It comes after previously forecast snowfall failed to arrive in the city over the weekend.
A yellow weather warning for snow is in place until 11.59pm on Wednesday.
On its website, the Met Office writes: ‘Frequent snow showers may lead to travel disruption in places. Some places are likely to miss the showers altogether.
‘Some roads and railways likely to be affected with longer journey times by road, bus and train services. Small chance of longer travel delays in places with some stranded vehicles and passengers, along with delayed or cancelled rail and air travel.
‘Some injuries from slips and falls on icy surfaces.
‘Probably some icy patches on some untreated roads, pavements and cycle paths.
‘There is a slight chance that some rural communities could become cut off.
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‘There is a small chance that power cuts will occur and other services, such as mobile phone coverage, may be affected.’
The snow is currently light but how long will this continue?
Here is what the latest Met Office forecast says:
Portsmouth
6pm – cloudy – 0C
7pm – cloudy – 0C
8pm – overcast – 0C
9pm – overcast– 0C
10pm – overcast– -0C
11pm – overcast– 0C
Midnight – snow showers – -1C
1am – overcast – -1C
2am – overcast – -1C
3am – overcast – -1C
4am – overcast – -1C
5am – overcast – -1C
6am – cloudy – -1C
7am – cloudy – -1C