Monthly Outlook

High pressure will deliver a lot of dry weather to the UK though the end of April and into early May, aside from some showers early in the coming week.

Before the middle of May unsettled and chillier conditions will probably develop, with temperatures near or below average, but warmer weather may return after mid-month, although still changeable.

A lot of dry weather. Occasional showers

With high pressure dominating, the weekend is going to remain mainly dry across the UK. Saturday will have a lot of sunshine across most areas, but south-west England is going to be breezy. There will be a tendency for cloud to increase on Sunday, with a few isolated showery outbreaks possible, chiefly over Northern Ireland and the north and west of Scotland, but many areas will be dry and warm.

Early in the coming week high pressure may become centred just to the west of the UK, allowing a front to move southwards and bring a scattering of sharp but hit-and-miss showers on Monday, with isolated thunderstorms possible.

The position of high pressure is uncertain through the rest of the week but it will most likely become centred near or over Scotland. This should hinder the approach of Atlantic frontal systems, so there should be a lot of dry weather from Tuesday to Thursday, with sunshine at times.

England and Wales will be breezy, especially towards southern coasts, and east to north-easterly winds will make eastern coasts cooler. Scotland and Northern Ireland should be calmer, with chances of overnight and early morning fog patches.

By Friday and into the May Bank Holiday weekend there are hints that high pressure could recede enough again to allow outbreaks of rain to develop, most probably in western areas - across parts of Scotland, Northern Ireland, Wales and south-west England.

Turning cooler and more unsettled

The position of high pressure remains important for weather conditions during early May but becomes less clear. High pressure anomalies could start somewhere near the UK, with rather low precipitation amounts and daytime temperatures a little above normal. With some calm conditions there could be a few chilly and foggy nights.

However, there are signs of a change, with high pressure receding more to the north-west and low pressure developing closer to the UK.

This should result in a change to cooler, wetter and breezier conditions at times, with temperatures more likely to be near or a little below average overall. It could get chilly enough for wintry showers over higher elevations in the northern UK.

Although this shift to more changeable weather is the most probable outcome, the timing is uncertain.

Changeable but possibly warmer later

The most likely pattern through this period keeps low pressure systems near the UK. As a result, there should be periods of wet and windy weather, with near-seasonal precipitation amounts. Eventually, the north of the UK could become wetter than the south. That would be due to high pressure building more strongly from the south-west, perhaps bringing a drier trend to southern regions.

This development would also bring a shift in wind patterns, with south-westerly flows becoming more common. As a result, the expectation is for an overall rise in temperatures, which should average out above normal before the end of the forecast period.

Temporary chillier interludes would remain possible between weather systems in this scenario, especially in the north of the UK.

In Tuesday's update we will re-examine the high-pressure dominance, and see if there is any greater clarity on the expected change to more low pressure presence and unsettled weather.