Monthly Outlook

A more unsettled and less warm period is expected during the coming week or two.

In the first half of September, high pressure may return to bring warmer and drier conditions again for a while.

Changeable and less warm

Temperatures will continue to moderate through the weekend. There will be a lot of dry weather with just a few hit-and-miss showers dotted around, aside from some more widespread rain over north and west Scotland. A weak ridge of high pressure across the UK will prevent that from spreading anywhere else.

Through the coming week, however, high pressure is likely to recede for a time, allowing Atlantic low pressure and frontal systems to move across the UK. This pattern will bring greater chances of occasional rain, which may be heavy in places, or showers and some isolated thunderstorms, with winds likely to become brisk at times as well. Some welcome rain should finally reach the south, and for the week overall, rainfall amounts should be near or above average for many areas.

Although the south may stay warmer than average for a couple of days, there will be a further cooling trend. For most regions, temperatures will be around average for the time of year. There is little chance of any notably hot days returning.

Unsettled conditions may continue

Although high pressure may try to reassert itself, unsettled weather is more likely than any return to a lasting dry period. Low pressure circulations and frontal systems are likely to impact the UK, brining further bouts of rain with scattered showers and brighter spells in between, and a chance of thunderstorms locally.

Rainfall amounts for the week are most likely to be near to above average. It is possible that high pressure may settle to the north-west, which might make the northern half of the UK, especially Scotland, drier than the south.

Chances of hot days will remain low but temperatures, although variable, should average out near normal across the northern UK and a little above for southern regions.

Potentially becoming drier and warmer

Confidence in the outlook is low for the first half of September, with longer-range models having no strong signals and depicting differing possibilities. Most probably, high pressure will build again across continental Europe at some point, and this may push warmer air towards the UK, with temperatures ending up higher than the September average. Although not approaching recent levels, there will be chances of a couple of very warm days in the south.

Conditions could stay changeable for a while but in some areas of the UK there may be increasing chances of some drier spells of a few days in a row returning, more likely for the southern UK than the north. The first week of September may have near-normal precipitation amounts overall, while the second week may be a little drier.

An alternate possibility is for high pressure to settle farther north, which would have a less-warm outcome, at least early in September, although even then there are few indications of any cool autumnal air arriving.

In Tuesday's update we will see if there is any more clarity on how pressure patterns will evolve heading into meteorological autumn, and whether it still looks like warming up again.