BBC monthly outlook
Summary
Stormy end of February but trending drier in March
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Saturday 29 February – Sunday 8 March
Stormy weekends bookend a calmer, cool week.
Storm Jorge will be moving across the UK this weekend bringing its full force to bear on Saturday. Strong winds for most of the country with heavy rain in the southwest and hill snow for North England and Scotland will make for quite the stormy day. Conditions will ease somewhat by Sunday, but it will still be quite breezy across the country, and snow is still likely in Scottish hills. Heading into the working week, Storm Jorge will abate as the weather turns a bit more benign for a time. The jet stream, a ribbon of fast-moving air in the upper atmosphere that drives weather systems, will dip south. Lately it has been over the UK giving us plenty of stormy weather in February, but as it heads south it will instead send those weather systems into Spain and Portugal. As a result, it will be a bit drier than it has been recently, but also feeling a bit colder than normal.
Some overnight frosts are likely this week making for some crisp mornings. It won't necessarily be completely dry though, especially in Scotland. Some rain is still likely in the west as well, which may drift into central and eastern areas occasionally. Heading into the first weekend of March, there are increasingly strong signals for yet another storm to move in from the west, bringing some wet and windy weather for the weekend. This would make the fifth consecutive weekend of unsettled weather! Confidence is only medium, however, as some models show a ridge of high pressure instead.
Monday 9 March – Sunday 15 March
Rain shifting north. More settled in the south.
Heading into the second full working week in March in the wake of the anticipated stormy weekend, we expect high pressure to build in by around midweek. This will mean that the weather pattern will change to a more settled, drier, and milder one. Temperatures will tend to be above average, but this will be most pronounced in the South as the high feeds in warmer sub-tropical air.
Low pressure will be pushed away to the north nearer to Iceland, but weak weather fronts will likely still be able to reach into Scotland and perhaps Northern Ireland. This will create a bit of a north-south split in the weather, with Wales and England being largely fine and dry while Scotland and Northern Ireland are wetter and windier. However, it will not be nearly as stormy as it has been, as these fronts are likely to be rather weak features.
The main uncertainty this week is how quickly high pressure will become established over the UK. It may take a bit longer than midweek, which would prolong the unsettled and cooler weather. The forecast models haven't quite made their minds up yet on when they might happen, but we do expect high pressure to be in place by the end of the working week.
Monday 16 March – Sunday 29 March
Staying settled at first but fronts returning.
By mid-March high pressure is expected to be firmly in place near or over the UK. The main uncertainty at this point is exactly where the ridge of high pressure will be centred. Settled weather is likely to be the norm for most, but Scotland will continue to see wetter and windier spells from weak fronts. If the high is a bit further west over the North Atlantic, wetter weather in Scotland will be able to creep into eastern areas as well, and a colder north-west wind will predominate. If the high is a bit too far northeast and closer to Scandinavia, this could send a colder easterly wind our direction as well.
However, if the high is centred near the south-west of the UK, as we expect it to be more often than not, the warmer sub-tropical air will be able to reach into the country and keep things on the milder side of average. Early spring high pressure centres can be tricky to forecast, as it is very easy for things to end up quite gloomy and grey under the high pressure. If it tends to be sunnier, temperatures will likely climb well above average. Towards the end of the month, low pressure systems are likely to begin to reach closer into the UK as the high declines. This will bring some wetter and windier weather into the northwestern parts of the country, but also increase the south-west winds, so more sub-tropical air will be fed into Wales and England.
Further ahead
We will take a closer look into the potentially stormy first weekend in March and pin down when drier weather will arrive as we head into meteorological spring.
https://www.bbc.co.uk/weather/outlook