Isle of Portland (Dorset) weather

Headline:

Turning fresher with heavy, possibly thundery showers.

Today:

Isolated, possibly heavy, showers are expected through the day, chiefly towards the north and west. However, many places staying dry with bright or sunny spells. Temperatures around average for the time of year. Maximum temperature 22 °C.

Tonight:

Further showers will move in from the west overnight, some of which could be heavy at times. More isolated in the east with clearer spells. A cooler night for many. Minimum temperature 9 °C.

Thursday:

A showery day on Thursday. Showers turning thundery at times as they move their way eastwards. Some hail possible too. Slightly cooler than Wednesday, but warm in any sunny spells. Maximum temperature 21 °C.

Outlook for Friday to Sunday:

Temperatures staying below average into the weekend. Scattered showers continuing on Friday, but slowly becoming more settled again heading into the weekend with an increasing number of sunny spells.

This period is likely to start largely dry and settled across the UK, as a ridge of high pressure sets in. A few showers are likely in the far north and possibly the far southeast though. Conditions look like turning increasingly unsettled through next week, as low pressure gradually becomes dominant, squeezing the ridge off to the northeast. Most places are likely to see some rain or showers, particularly during the second half of next week, and these may be heavy with a risk of hail and thunder. It may become breezy if not windy at times too. Temperatures are likely to be near or a little below normal overall, with some chilly nights at first, but brief warm, humid spells are possible at times, especially in the south.

As we move into the start of meteorological autumn, it looks like it will start rather unsettled. However, signals for the prevailing weather patterns affecting the UK soon become weak, with something close to the climatological norm becoming most likely. This means a broad northwest-southeast split in conditions, with higher pressure becoming centred close to the south of the UK and lower pressure towards the north or northwest. The north and northwest will probably see the lion's share of the rain and any strong winds, whilst the south and southeast will probably see the driest and sunniest weather. Temperatures are likely to be a little above average overall. There is a chance that late season hot spells or heatwaves develop, especially in the south.