Updated 25th July
Covering the period 1st August - 23rd August
Cloudy first week away from the south-east, then often dry, sunny and warm in the west, cloudier and cooler at times in the east
Mean temperatures, relative to the 1981-2010 average, will be 1 to 2C above normal in most western areas, but generally between 0 and 1C above in eastern Britain.
Rainfall totals will be below normal in most parts of the UK, but the wet first week will raise rainfall totals close to the long-term average in Northern Ireland and north Wales.
Despite a cloudy first week of the period, it will be sunnier than average in most western parts of the UK, but with southern England, and the east of Scotland and England, having close to average sunshine.
Monday 1st August - Sunday 7th August
This week will begin and end on a fairly quiet note for most, but will be changeable in the middle.
On the 1st, a ridge of high pressure will cover the southern half of Britain, giving most parts a dry and bright day with plenty of sunshine in the south, but Northern Ireland and the north and west of Scotland will be cloudier, with some rain spreading in from the North Atlantic at times. Temperatures will be close to the seasonal average. On the 2nd and 3rd, cloudier and breezy conditions with some rain will spread slowly south-eastwards, but it will warm up in southern and eastern regions. Much of East Anglia and south-east England will be sunny, with highs of 25 to 27C in many places.
Between the 4th and 6th the weather will be unsettled with shallow low pressure in control of the weather, bringing some slow-moving belts of rain and, in between the rain belts, a mix of sunny intervals and scattered showers. Thunder is not expected to be widespread during this unsettled spell. However, high pressure will ridge into western areas on the 6th turning the weather drier in the west, and by the 7th, high pressure is expected to cover most of the country, bringing mostly dry conditions, albeit rather cloudy for many parts of the country, with a little drizzle from weak frontal systems. Coastal parts of the south-west are most likely to be sunny. Temperatures, after the warm interlude on the 2nd/3rd, will return close to the seasonal average.
Mean temperatures will mostly be within a degree of the 1981-2010 average but it will be about 1C warmer than average over much of eastern and southern England.
Rainfall totals will show a marked north-south split, with most of Scotland, Northern Ireland and northern England rather wetter than average (especially Northern Ireland), but it will be much drier than average across the southern third of England and in south-east Wales.
Sunshine totals will be above normal in East Anglia and most of south-eastern and central southern England, but mostly below normal elsewhere, especially Northern Ireland, south-west Scotland and north-west England.
Monday 8th August - Sunday 14th August
This period will be more settled with high pressure often ridging northwards from the Azores, and with Britain often on the eastern flank of the ridge. It will thus be drier than average almost everywhere, although isolated thundery downpours will develop on some afternoons, resulting in locally swollen rainfall totals. It will be warmer and sunnier than average over much of Scotland, Northern Ireland, Wales and the western side of England, but north-easterly winds will blow more frequently than usual, resulting in relatively cloudy and cool conditions spreading southwards down the eastern side of the country. This will affect eastern coastal parts of Scotland and will be more widespread across the eastern side of England.
The mean temperature for this week will be 1 to 2C above average across most of northern and western Britain, but southern and eastern England and the east coast of Scotland will have a close to or fractionally below average mean temperature. It will be drier than average everywhere, but sunshine will be quite variable; somewhat above average in the west, but near or rather below average in eastern and southern England.
Rest of the month
Monday 15th August - Tuesday 23rd August
There will be a weaker-than-usual westerly flow over the British Isles during this period, with pressure slightly above average, implying that western Britain, in particular, will end up rather warmer, drier and sunnier than average. Early in the period, with high pressure ridging further east, much of the country will have predominantly warm, dry and sunny weather, but it will turn less settled towards the end of the period with shallow and possibly thundery low pressure systems interrupting the fine weather.
Temperatures will mostly be 1 to 2C above normal in the west, but less than 1C above in the east. Rainfall totals will mostly be below normal but are more likely to be close to normal in southern England and south Wales. Sunshine will be above average, especially in the west and north.