Long range forecast from Positive Weather solutions ,who have been more accurate than the Met Office !
June – Some warmth, occasional heavy rain / thunder
June will see some good temperatures, but any sustained warmth is likely to break down quite quickly, with spells of heavy and often thundery rain developing from time to time. Generally speaking it will be a very mixed month, and the nature of localised rainfall means that almost anywhere across the country could be susceptible to deluges and associated flash-flooding. Temperatures will reflect an average June, with some reasonable warmth for most areas - especially in southern regions - but also some lengthy cooler spells. On balance, rainfall totals appear just above the norm – more so in northern regions.
July – Drier South / Wetter North
July appears to offer a more definite pattern, with many parts experiencing fair or changeable conditions – some sun, though often with a lot of cloud. More unsettled weather at times will tend to spoil things for northern and western regions of Britain and Ireland, where wetter episodes may be commonplace. Meanwhile lengthy passages of drier weather can be expected too - especially towards the south and east, where it will often feel very warm. Even here however such periods are unlikely to last for very long before cooler and cloudier conditions return. Temperatures will be just above or average for most; rainfall looks set to be above the norm in some northern parts.
August – Dry, some warmth
August generally across much of the British Isles could be the most encouraging month of summer. Rainfall looks likely to be reduced across many areas. There will be some spells of good weather and in many southern parts it will often feel very warm and humid, especially during the first couple of weeks. A drier than average month will result across most parts of Britain and Ireland, with temperatures generally close to the norm for most regions. At this stage the most noteworthy aspect of the whole summer may concern a lack of rain, particularly for some southern and eastern regions. PWS will re-appraise this critical aspect of Summer 2011 forecast in its May update.