Often with a change of month comes a change of weather. And weather models this morning suggest this phrase will hold true.

Looking back over the last ten years August has been the wettest summer month on five occasions. Given that June rainfall was just 38% of average and July rainfall currently (as I write this on 25th) just 28% of average, it is not surprising that August could potentially be the wettest summer month.

The Atlantic looks like it will have cranked back into action by the first week of August bringing us a period of more unsettled weather – a more mobile westerly flow which means cooler conditions than we experienced during most of July.

The first week looks the most unsettled – no huge rainfall totals though there will be rain or showers around, some of them potentially thundery. Temperatures in the low 20s – though up to 25C on any brighter days.

The second week could start quite thundery with potential for a heavy downpour. After this I would expect the Azores high to ridge northwards settling down the weather to give possibly the best weather of the month during the third week – temperatures still in the low to mid 20s with lots of sunshine around and cool nights.

As the high pressure shifts, bringing a more east or south-easterly flow, days could become briefly very warm at the start of the fourth week. However the high pressure could start to drift north as the wider pattern begins to respond to a very active US hurricane season. Though it is a long way off all that extra energy in the Atlantic will begin to feed through to us at the end of the month, turning things unsettled again in time for the August Bank Holiday. September could be very wet indeed.

So in summary the buzzword for August is average overall with decent sunny summer’s days coupled with the odd rainy or showery day. No return of the heatwave – but also not the washout of the last few summers.

Average max temp: 22.5C (normal)
Average min temp: 12.5C (slightly below normal)
Rainfall: 57mm (normal) – this estimated total could be quite conservative in the event of any potent thunderstorms

Scott Whitehead
@wanstead_meteo
http://www.wansteadweather.co.uk