So you've heard, it's going to turn cold next week.

But why are we hearing so much about it, when will it arrive, how will it affect Scotland and how long is it going to last?

All questions I know you're bursting to ask, so I thought I'd answer them for you.

This cold spell is a little different to others we've had this winter. Most of our cold weather has come from unsettled spells associated with low pressure systems coming in from the Atlantic. We've also had unusually cold westerly winds at times this winter because eastern Canada has been colder than usual. While that air has been warmed by the Atlantic by the time it has reached us, it's still been cold enough for snow.

Because most of the cold air has come from the west and north west so far this winter, places like Ayr and Glasgow have seen more snow days than previous winters, and this is also why Dundee and Aberdeen have seen very little - due to the shelter from the Grampians.

This cold event is different because it's down to something called sudden stratospheric warming (SSW), which occurred several miles above the North Pole just over a week ago. In just a few days, the temperature rose about 50 degrees in the stratosphere.

The sudden rise in temperature is due to lower level winds reaching higher altitudes around the Arctic. This process can eventually break up and slow down the upper level westerly jet which circles the Arctic, and sometimes, as on this occasion, force the winds to turn easterly instead. These easterly winds then slowly descend towards the surface over the course of a week or so, and result in dramatic changes in weather type, for example in Europe, the easterlies can bring very cold air out of Russia.

In the winter several minor stratospheric warming events take place, but it's only every few years that a major warming event takes place, such as this one.

So, what's happening at the surface, you know, where we live?

Well those of you that have been getting my updates on Twitter, Facebook or on the TV will probably know by now.

A large area of high pressure (settled weather) which normally sits over the Azores in the Atlantic has been on the move this week. It drifted across Scotland on Wednesday and Thursday giving us a lot of dry and sunny weather, but it's now centred over Scandinavia. Because winds in high pressure go around the centre in a clockwise direction, the air has started getting dragged out of Siberia. Temperatures in Siberia have been around -30C to -25C by day this week, and this very cold air has started to move west towards Europe.

For the UK, the proper cold air spreads in from the North Sea on Sunday night with the risk of some light wintry flurries along the east coast for the likes of Angus, Fife and Aberdeenshire. Snow showers are likely to become heavier and more frequent into next week, from around Tuesday. In Scotland with an easterly wind, the worst is always more likely in eastern areas, although some will get further west, especially through the lowlands.

In situations like this, where very cold air is travelling across the relatively warmer North Sea, we can get a bit of a 'lake effect', where heavy snow showers become frequent and merge into longer spells of snow at short notice, something I will be monitoring closely throughout next week.

I can see you scratching your head, yes, what about it? It's snow, it's cold, right? Yes, but it could be the wrong type of snow for some of you. While snow will have most of your running for the sledge and getting the mittens on to build snowmen, just wait.

Sledging will be ok, but for those of you trying to make a snowball or roll the body of snowman, you may be disappointed. Because the air coming in will be so cold, the snow will be dry and powdery rather than our usual wet stuff. This means the snow doesn't stick together as well, and we are left just to throw it in the air for fun instead.

Enough about the snow, how cold will it get and will it beat any records?

This is likely to be the coldest air to sweep the UK for a few years and falls into the very unusual category for the south and southeast of England.

For us in Scotland, temperatures by day will start around 4C early next week, and drop to nearer freezing by midweek. Even though the air is very cold, the overnight temperatures for most will probably not be too exceptional, due to the fact it will be windy and fairly cloudy. The wind and the dryness of the air will lead to a significant wind chill.

If somewhere in the Highlands does get a night of lighter winds with clear skies later in the week, it could drop to -15C or below.

This really will be the icing on the cake to a winter which has had far more cold spells than recent winters, when the weather has been more about wind, rain and storms.

But the big question, could this cold spell be a record breaker? There could be some individual location records broken in the next few weeks, but the March record still looks safe, at least through next week. The record low for March is -22.8C, which was observed at Logie Coldstone, Aberdeenshire back in 1958.

Well, that's open to a lot of debate. We watch many forecast computer models which usually show a theme, but can also show very different individual outcomes as time goes on.

So there's no hard and fast answer to this, but there is good agreement for this cold and wintry spell to last for a few weeks, but stay tuned for all the latest.

This could be a winter bite we're talking about for some time after...