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UK Long Range Weather Forecast

UK Long Range Weather Forecast

Our Long Range Forecast provides you with the expected weather over the next 3 – 4 weeks. . Using longer range forecasting techniques we can provide a solid guide as to the expected weather and possible trends in temperatures and rainfall..

Longer Term Forecast and Trends – Tuesday 25th August to Monday 21st September 2015


The rest of August will maintain rather changeable and often unsettled conditions with some temporary, drier and brighter conditions but equally there will remain a lot of unsettled conditions too. However, the signal for improving conditions into the opening week of September remains and a fine and settled start to September is still expected with increasing amounts of dry weather, albeit with still rather cool temperatures. As the remainder of September progresses a progression towards rather ‘typical’ September weather is expected which is likely to signal increasing amounts of wet and windy weather, but with some drier and brighter weather at times.


 Average Mean Temperature for the Forecast Period: 17C


WEEK 1 (25th to 31st August):

Summary: Generally little change with further unsettled conditions expected.

Temperatures are forecast to be near or perhaps slightly below average by 1C or 2C during this week, especially during spells of rain and showers. There is little or no risk of any very warm or hot weather during this week and to end August. Rainfall totals are likely to average out near to average with some further spells of rain and showers at times, especially across more northern areas, whilst southern areas continue to experience a greater risk of drier conditions. High confidence to suggest that August will end with further changeable conditions dominating across most areas. Spells of rain and showers will be interspersed with some temporary drier and brighter conditions, but emphasis is on quite cool and often unsettled conditions.


WEEK 2 (1st to 7th Sept):

Summary: Generally drier and more settled into early September.

Temperatures are forecast to be near or perhaps slightly below average still, but only by a 1C or 2C at very most. It will feel pleasant though in any sunshine as fine and settled conditions generally dominate, though some chilly nights are possible. Rainfall totals are expected to be slightly below or below average given that overall a drier than average week is expected as high pressure develops to produce dry and fine conditions. Rainfall totals may trend back to nearer average to end the week as more unsettled conditions potentially develop, but overall a dry week is currently expected. Medium to high confidence now for the opening week of September to produce some fine and settled conditions as high pressure develops. This will signal mainly dry conditions with some bright or sunny spells, albeit with no significant rise in temperatures. Nights may well be quite chilly and some mist and fog may also be possible given the time of year now.


WEEK 3 (8th to 14th Sept):

Summary: Increasingly unsettled and potentially autumnal, generally remaining quite cool as well.

Temperatures are forecast to be near to, or perhaps slightly below average by around 1C or 2C at the moment given some signs that signal cooler conditions developing as we progress towards mid-September. Rainfall totals are likely to recover back to nearer average values than compared with the previous week with a greater risk of rain and showers developing through the week as low pressure systems become more influential. Low to medium confidence for now, but after a possible fine and dry start to September, there are signs that as the month progresses it will start to become more unsettled and potentially more autumnal with low pressure and cooler conditions developing by the time we approach the middle of the month.


WEEK 4 (15th to 21st Sept):

Summary: A generally ‘typical’ mid-to-late period of September weather is currently expected which signals generally average temperatures, so increasingly cool and potentially quite autumnal at times with a risk of wet and windy conditions.

Temperatures, at the moment, are likely to be near to average overall which will signal increasingly cool weather, but a few warmer days still remain possible. Some chilly nights may also be possible too. Rainfall totals are forecast to be near to average, though perhaps trending slightly above average across more northern regions. Periods of wet and windy weather may well be interspersed with some temporary drier conditions, hence, overall, near average rainfall totals are currently expected. Low confidence for now to suggest rather typical and average mid-to-late September weather will be in evidence after mid-month which signals a likely mixture of some rain and showers with some temporary drier, brighter and locally warmer days too.