Across northern England and the Midlands between 28 November and 5 December average temperatures will be around or less than 2C (35F), according to the Met Office.

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The National Grid is also asking people with smart meters to lower their energy use on Wednesday to take pressure off the grid during the current cold snap.

Here we look at how best to heat your home to stay warm as temperatures plummet.

What temperature should I have the heating on?

The World Health Organisation recommends heating your home at 18C (64F) in the winter, while the Energy Saving Trust suggests anything between 18C and 21C (70F).

But this varies for children, the elderly and clinically vulnerable.

According to the Lullaby Trust, although it may be tempting to turn up the heat to keep newborn babies warm, the room they sleep in should be neither too hot nor too cold to avoid the risk of sudden infant death syndrome.

Babies' rooms should therefore be between 16C (61F) and 20C (68F) - as research suggests they are better off sleeping in cooler conditions where possible.

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Age UK advises older people to heat the rooms they spend most time in at around 21C and the rest of their home to at least 18C.

Temperatures below 12C (54F) risk hypothermia in the elderly, while anything above 24C (75F) can increase the possibility of strokes or heart attack, the charity says.

Should I open windows to avoid mould?

Opening windows while the heating is on means you might be unable to reach the temperature you've set on the thermostat - and will waste money on your bills.

But research suggests opening your windows for five to 15 minutes a day improves air quality and avoids health risks associated with mould.

Try to ventilate your home at points in the day when you don't have the heating on.

If you have an air purifier, you may not need to open the windows to ventilate your home, however.

Are curtains or blinds better - and should I keep them closed?

While both curtains and blinds help with overall insulation, heat can escape through blind slats, making curtains better insulators.

But during hotter periods blinds are more energy efficient - so you should make your decision based on year-round temperatures where you live.

Temperatures drop when it gets dark, so closing curtains and blinds at night - and when you're not home - will help keep the heat in.

For people with wood or laminate floors, rugs can also help with insulation.

Should I leave the heating on when I'm away?

You only need to keep your heating on when you're not at home if temperatures are due to drop around freezing.

This is because water could freeze inside your pipes and cause a flood.

British Gas recommends keeping your thermostat on at least 7C (44F) when you're not home during these periods - particularly if you are away for more than a day.

Pets are rarely left on their own for more than a day - so it's unnecessary to keep your heating on for them.

Does foil behind a radiator really work?

Yes. Foil reflects heat, so placing some behind your radiator will push it back into the room, heating it up faster and helping to retain warmth.

Make sure you wrap the foil around a thin sheet of card and cover it completely to avoid any fire risk.

Making it T-shaped so it can fit around the brackets of your radiator will make it even more efficient.

You can also buy ready-made foil insulation.

Ovens, draft excluders and other tips

Ovens take a while to cool down after they've been used, so keeping the door open after you've finished cooking means you can recycle the extra heat to keep the kitchen warm.

You can also buy draft excluders you can cut to the length of your doors to help fill in gaps that are letting heat escape.

The Energy Saving Trust also reminds people to bleed their radiators around twice a year to make sure they're working efficiently.