Rainfall totals for the UK were appreciably above average during the month of July. All regions reported at least 90% of the 1971-2000 average and rainfall deficiencies across most of southern Britain have moderated. However, spatial variations in rainfall within some regions were considerable with below average totals reinforcing meteorological drought conditions in parts of central England.

Relative to the monthly average, river runoff rates are significantly healthier than in the late spring but depressed flows continue to characterise rivers in parts of central and southern England. After almost six months with very meagre infiltration, the hydrological impact of the drought is now clearly evident in the low, to very low, groundwater levels across most of the major aquifer outcrop areas.

Rainfall

At the national scale, July rainfall was above average for the 5th successive year. Much of north-east Britain was especially wet with rainfall exceeding twice the July average in some areas (e.g. the Cairngorms). Provisional data indicate that Scotland reported its highest May-July rainfall whilst, in the March-July timeframe, England registered its lowest rainfall for 15 years. Rainfall deficiencies over the last five months are most notable in the Midlands and Yorkshire (provisionally reporting their 4th and 5th lowest March-July rainfall respectively since 1921). Some parts of the Midlands have recorded only 2 months with above average rainfall in the last 20 months.

Groundwater deficits still high

Soils are close to saturation across most of northern Britain but soil moisture deficits remain considerably above the early August average across the outcrops of most major aquifers. The dryness of the soils precluded any significant groundwater replenishment during July and, generally, groundwater level recessions continued

Jamie Hannaford from the Centre for Ecology & Hydrology said, "With end-of-July soil moisture deficits remaining close to record maxima in parts of central England a substantial delay in the seasonal recovery in runoff and recharge rates may be expected. The autumn rainfall will be very influential in determining whether drought stress will extend into 2012."

Met Office Outlook

UK Outlook for Weds 17 Aug to Fri 26 Aug 2011:
The period starts rather wet and unsettled over many parts, with spells of rain moving erratically eastwards towards the weekend. Near-average temperatures for most will be tempered towards the northwest by the brisk wind here at times. Meanwhile, southeastern parts of the country look favoured for the warmest weather, however this comes coupled with an increasing chance of heavy or thundery showers at times up to and over the weekend. At the same time, other parts of the UK should see fairer weather, with a few showers but also some bright or sunny spells. The final week of the period should again see unsettled weather spread into the northwest, with the UK as a whole most likely seeing a return to unsettled conditions, with winds from the westerly quadrant.

UK Outlook for Sat 27 Aug to Sat 10 Sep 2011:
A generally unsettled period, with little in the way of dominant weather patterns. Both rainfall and sunshine amounts for the UK should be near-average for late summer, with the southeast of England the one exception to this, being most likely wetter and cloudier than normal. Mean, minimum and maximum temperatures will most likely be below average across the country, perhaps closest to normal in some central and western parts, whilst the southeast may even fall well-below normal at times.

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Rainfall figures below - National Environmental Research Council - Centre for Ecology and Hydrology.

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