On the Horizon – Big changes coming up – UPDATE!

John gives us his latest thoughts on likely weather trends over the next few weeks. SEE UPDATE ON COMING WEEKEND…

MONDAY 13TH  NOVEMBER – SUNDAY 19TH NOVEMBER

Chopping and changing – Cold and frosty start… turning damper and milder for a time

Following a bright and crisp Remembrance Sunday, the new week starts with a sharp frost. After a fine start to Monday, cloud will spread across the sky, making it feel chilly. It may be the coldest day of the Autumn so far – with rain into the northwest of the UK later.

Weather fronts will be heading in across the UK over the following day or so, which means that through the midweek period we should expect some rain. Having said that, many southern and eastern parts of the UK will see relatively little wet weather compared with some northwestern areas. Temperatures will recover for a time with frost less likely. But some patchy morning fog may linger where winds stay lightest.

By the end of the week there are the first signs of another change.

…take your long-range app forecasts with a pinch of salt

A more energetic weather front will sweep across the UK. That brings the prospect of a longer spell of rain. It could get quite windy too, especially across northern areas.

It will then become chillier again and the showers that follow may begin to turn wintry over northern hills. Through the weekend, another wet weather system may well cross the UK from the west. There is a huge amount of uncertainty on this, and the path of such a system is crucial.

Why? Because on its northern flank, as it hits the cold air, we may see a period of significant snowfall – the first of the season for many. At this stage, northern parts of the UK are most prone to this possibility.

MONDAY 20TH NOVEMBER – SUNDAY 26TH NOVEMBER

The fridge door is opening… cold air creeps into the kitchen

I’m sensing quite a significant change across much of the northern hemisphere. The weather machine looks like slowing down – almost to a standstill. The normal procession of jet stream winds will become increasingly distorted into what’s termed a ‘blocked’ pattern.

So what? Well when this happens, warm and cold areas can begin to meander off course – warm air into the Arctic and colder air further south.

So instead of looking to the mild Atlantic for our weather, we must prepare for some of that much colder air to escape out of the Arctic and towards us – either directly from the north or in a loop from the east.

The day-to-day details will still  only be clearer nearer the time. So take your long-range app forecasts with a pinch of salt.

But the trends are now beginning to fall into place . Much colder weather will become established across the UK. It should be drier than in previous weeks. But what showers do occur, will fall as snow in some places, especially, of course, on the hills in northern parts of the UK. Frosts will become more widespread.

MONDAY 27TH NOVEMBER – SUNDAY 10TH DECEMBER

How long and strong will the cold hold?

With the likely advent of colder weather, the next dilemma is how harsh it might be and how long it will last. Again the computers will have big problems deciding when and if ‘normal service’ resumes and milder Atlantic weather systems sweep away the cold.
Current indications are that such systems will continue to be ‘blocked’ from doing so as we head into early December. So the chance of frost and, more importantly, snow remains higher than normal, initially at least.

We’ll update you on how severe and long-lived any wintry weather will be. But prepare for a big change after what’s been a relatively mild Autumn so far. Layers required, I’d suggest, for those Christmas markets.

“White Christmas?”, I hear you ask. Don’t be ridiculous! It’s FAR too soon to tell.