BBC monthly outlook
Summary
Colder through mid-February but largely dry
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Wednesday 3 February – Sunday 7 February
Unsettled week with a colder weekend
From midweek through to the end of the working week, a low pressure system is expected to linger over the UK and bring quite a lot of unsettled weather. Heavy snow is expected most days for Scotland, generally above 200m, and occasionally into northern England too. Heavy rain is expected in the north and northeast as well with the low pressure centre often sat in the Midlands. Southern areas will be a bit more variable with occasional rain mixed with some sunny spells at times.
This weekend though, we are in for a change as high pressure builds to the north of Europe. This will gradually push the weak low over the UK southwards towards France. As the low moves south, a cold easterly wind will develop, first in Scotland and then spreading south through Saturday and Sunday.
The high will be bringing colder air from northwest Russia through the Baltic and North Seas and into the UK. As the colder air crosses the relatively warmer North Sea, heavy showers are likely to develop and move into eastern and central parts of Britain. With the colder polar airmass, these showers may fall as snow even to low levels, possibly as low as sea level. Western areas will tend to remain dry but cold once the low clears away to the south.
Confidence is reasonably high for the rest of this week, but there is still some uncertainty on how quickly the low will clear away to the south and it may linger through the weekend. The risk is for a milder and wetter weekend for southern areas.
Monday 8 February – Sunday 14 February
Colder, potentially snowy start to the week
In mid-February, high pressure is expected to remain over Scandinavia throughout the week, keeping things rather cold. This setup is similar to the classic "Beast from the East" from 2018, and there is potential for some heavy snow showers for eastern areas for the first half of the week. This is very sensitive to the strength of the high to the northeast, so it is still a bit too early to accurately predict snow amounts, but the greatest chances are in the eastern and central parts of Britain. We have high confidence that the high pressure system will develop, and it will turn colder than normal. The coldest days will tend to be around midweek as the air from Russia finally arrives in force.
Later in the week, the high in Scandinavia is expected to shift slightly further south and southeast, nearer to Belarus or western Russia. This shift should kill off any easterly winds through the North Sea, shifting them more southeast. This is still a cold flow for us in this setup, but much less cold than the first half of the week is expected to be. This weather pattern is also drier for the UK, so some crisp afternoon sunshine is expected. Without a cold flow over the relative warm North Sea, the risk of lowland snow showers is also lower.
The main risk to the mid-February forecast is for the easterly winds to linger for longer into the second half of the week if the high pressure system stubbornly remains over Scandinavia. This would make for a very cold, windy week across the country, but more so for eastern areas where it will feel very raw outside.
Monday 15 February – Sunday 28 February
Cold, dry middle of the month; milder later
For the second half of February, the drier and colder pattern from mid-February is expected to continue for the third week of the month. High pressure is likely to remain strong to the north of Europe and into northeast and eastern Europe, resulting in some colder air sticking around for the UK as low pressure systems travel south into the Mediterranean. There is a chance for a few brief mild spells to break up the cold as weak fronts find their way into the UK from the southwest, but these are expected to be short-lived 1-2 day events.
For the final week of February, high pressure to the north of Europe is expected to slowly decline and shift further away, allowing the jet stream, a ribbon of fast-moving air in the upper atmosphere that drives weather systems, to return to northern Europe. This type of pattern allows Atlantic weather systems to bring wetter but milder air in from the sub-tropical Atlantic as cold air becomes increasingly confined to Russia and Scandinavia.
There is some uncertainty on the exact timing of the pattern shift though, and these cold winter highs tend to be rather tenacious and slow to decline. The main risk for late February is that high pressure and colder air stick around through the end of the month and into early March, making for a cold but somewhat dry February overall.
https://www.bbc.co.uk/weather/outlook
