BBC monthly outlook
Summary
Unsettled and mild weather to come
Monday 3 December—Sunday 9 December
Wet and breezy but often mild in the south.
Cloudy at times with showers and some longer outbreaks of rain. Monday is expected to have a mixture of bright spells and banks of cloud with showers in places. There is a risk of some heavy showers over southern areas of Britain while northern Scotland will have a risk of more prolonged rain and upland snow in the morning.
After a chilly but bright start for many, Tuesday is expected to see rain and brisk winds spreading north-eastwards through the day and into the night with a risk of hill snow for a time over northern England and in Scotland.
The remainder of this week is likely to see changeable conditions with further rain spreading from the west at times. The south looks set to be mild. However, there are chances of somewhat brighter but chillier conditions spreading from the north-west next weekend.
Monday 10 December—Sunday 16 December
Very wet at times but generally mild.
In the second full week of December, we are likely to see a return of rain and brisk winds as low pressure areas re-emerge from the Atlantic. Generally, a lot of cloud is likely at times with outbreaks of rain spreading from west to east across the UK. Temperatures are expected to be mostly above the seasonal average. However, Scotland could be cold enough at times for some occasional snow mixed-in over hills. Indications are for wettest conditions to be over western areas of the UK, where high rainfall totals could produce local flooding. It is also likely to be windy at times, particularly over western areas of the UK.
There appears to be only a slight risk of colder easterly winds developing for a time around the middle of the week. Most likely, though, is for a generally mild, wet and breezy pattern.
Monday 17 December—Sunday 30 December
Wet, windy and mild.
Indications are that the second half of the month will be characterised by wet, windy and mild conditions with a strong jet stream moving in from the Atlantic at times. The jet stream is a ribbon of strong winds in the upper atmosphere which helps to drive in weather systems that bring wet and windy conditions to the UK. Western areas of the UK are expected to see the most rain. There are indications that rainfall could be well-above normal for December, bringing a risk of flooding.
Strong winds appear likely at times, perhaps most likely towards the end of the month. However, the positioning of the jet stream will dictate where the wettest conditions will be. There are chances that the jet stream lifts northwards for a time before Christmas to bring a brief drier period of weather to southern areas. After Christmas, there appears to be some risk that the jet stream drifts further south, bringing a risk of colder conditions into northern parts of the UK.
Anyone hoping for a white Christmas could end up being disappointed. However, it is still far too early to say for certain what weather we will have on 25th December. Even in some of the mild Decembers of the past few decades, short-lived cold spells did crop up and even produced short spells of snow. A green Christmas is not guaranteed...yet.
Next Update
We will take another look at the month ahead to see if we are still on track for a mostly wet, windy and mild December.
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