Who is striking? How walkouts on Wednesday 14 December will affect you

The UK suffered its chilliest night in almost two years on Monday night and there's no sign of the cold snap easing yet. There's also no sign of a thaw in the row between workers and companies.

Countrywide disruption, which started on Tuesday with the 48-hour rail strike, goes up a notch on Wednesday when postal workers stage a national walk out as well.

Only one in five trains is set to run. No Christmas cards will be delivered.

So has everyone had enough of this disruption? Well, not necessarily.

The latest poll by Savanta Comres suggests a very small drop in overall public support - 61% backed the strikes at the end of October and 32% opposed them, while the poll last weekend shows 60% supporting the strikes and 35% against.

When you break down the figures into specific jobs, nurses have more public support than those working on the railways.

• Post and rail workers walk out on Wednesday as strikes build

This is my latest briefing for you - keeping you up to date with useful information about how the latest wave of strikes might affect your daily life.

So what will Wednesday look like?

Another Royal Mail strike

Postal workers will strike again on Wednesday and Thursday - only a few days after they last walked out.

Royal Mail claims the postal workers' support for the strikes is weakening - and that 11,000 crossed the picket line this month, compared with 3,000 in August. But the Communication Workers Union (CWU) is having none of it - it says it's all spin and plans more strike action in January.

Delivering our Christmas pressies on time is, admits Royal Mail "challenging". Hardly surprising when you consider the company is relying on 11,000 managers and agency workers to fill in for more than 100,000 striking posties.

On strike days:

• Royal Mail says it will not be able to deliver first and second class letters - but will try to deliver as many parcels and Special Delivery letters as possible

• People will not be able to claim compensation for late deliveries

• Letters will not be collected from post boxes

• Royal Mail delivery offices will be closed, as will customer service points

• Post offices will be open as normal for bill payments and banking - because they are separate from Royal Mail - although some services, such as posting letters, may be affected

The CWU also plans industrial action on 23 and 24 December.

The final suggested dates for sending Christmas post have been brought forward:

• First class mail is now Friday 16 December (instead of 21 December)

• Second class was Monday 12 December (instead of 19 December)

Rail disruption continues

Tuesday saw widespread disruption and significantly reduced train services across England, Wales and Scotland - and Wednesday is likely to be the same.

The RMT union is on strike until 23:59 on Wednesday.

The Transport Secretary Mark Harper says the tide of public opinion is turning against the strike. Is that true?

The Savanta Comres poll suggests a small drop in public support since the end of October. Then it showed 50% in support of, and 29% opposed, to strike action. The updated survey, from last weekend, showed 47% in support versus 34% opposed.

You are advised to avoid taking trains, but if you must travel:

• Make sure you check with your rail operator before setting out to see what trains are running

• Be prepared for no services at all on some routes

• Be prepared for no early morning or late night services on other routes

• Expect busy carriages with only one in five services operating between 07:30 - 18:30 GMT

On Thursday, timetables will be closer to normal, but early morning services are likely to be disrupted as trains and staff may be in the wrong place.

And then, on Friday, it starts all over again. The RMT is due to walk out for 48 hours until the end of Saturday.

The union is also planning further action over Christmas and in the New Year.

• When are the train strikes? - read our guide

• Which lines are affected? - information from Network Rail

Watch Make Sense of Strikes on iPlayer and find out more about why people are striking and whether industrial action works.

Driving tests cancelled

Civil servants in the Public and Commercial Services Union (PCS) - including driving examiners - are striking most days now until early January.

But the industrial action is regional - with different areas affected each week. This week, until Sunday 18 December, the walk out is in north-east England and Scotland.

Next week, it moves to north-west England and Yorkshire and the Humber.

Check the government website for full details.

Some vehicle testing and enforcement services might also be unavailable.

What strikes are happening on Thursday?

We will have another briefing for you from teatime on Wednesday - looking ahead to Thursday's disruption. Nurses in England, Wales and Northern Ireland are set to strike that day over pay.

The walkout will involve Royal College of Nursing (RCN) members in more than half of hospitals and community teams.

• Search for affected NHS organisations in your area

Under trade union laws, life-preserving care has to be provided - so all nursing staff would be expected to work in services such as intensive and emergency care.

• How will the nurses' strike affect patients? - read our guide

Check out our a full rundown of all the December and January strikes.

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