Results from a series of boundary layer measurements carried out at Ashchurch, Worcestershire during July 1976 are combined with those from the 1973 Minnesota experiment. This data set provides a more complete description of the behaviour of some turbulence statistics through the depth of the convective boundary layer and into the stable air of the free atmosphere. Although the two experimental regions differ quite markedly topographically, the two sets of data are found to merge together quite well in the middle of the boundary layer and do not reveal any systematic differences that might be attributable to surface effects. The vertical profiles of turbulence statistics are compared, where possible, with other results from numerical models and laboratory experiments.

Lake Victoria in East Africa is one of the world's largest freshwater lakes and is used on a daily basis by thousands of fishermen. Each year, severe storms on the lake cause multiple boating accidents which often result in fatalities. Recent initiatives have seen an effort to reduce accidents by issuing storm warnings when severe weather is expected. Here the Met Office global Unified Model is evaluated along with a 4 km limited-area model which has been set up to assist forecasters in the region to issue these warnings. Findings indicate the 4 km model is capable of producing more realistic strong wind speeds and rain rates than the global model. Case studies relating to fatal boating accidents on 1 March and 4 March 2012, showed improved warning signals of severe storms in the 4 km model compared to the global model. Objective comparisons between model and observations were conducted on 2 months of data. An objective method was used to determine 'storm'/'no storm' in the model forecasts. These were then compared against cloud top temperature from IR satellite and lightning data from the arrival time difference (ATD) radio ground network to determine whether each model was successful at forecasting storm/calm events. The 4 km model was able to capture more storm hits (thus had fewer storm misses), but also gained more false alarm events. Overall, the objective analysis showed that both models had some predictive skill and both were an improvement on a persistence forecast.

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Bridging the gap between rapidly moving scientific research and specific forecasting tools, Meteorology of Tropical West Africa: The Forecasters’ Handbook gives unprecedented access to the latest science for the region’s forecasters, researchers, and students and combines this with pragmatic approaches to forecasting. It is set to change the way tropical meteorology is learned and will serve to drive demand for new forecasting tools. The Forecasters’ Handbook builds upon the legacy of the African Monsoon Multidisciplinary Analysis (AMMA) project, making the latest science applicable to forecasting in the region. By bringing together, at the outset, researchers and forecasters from across the region, and linking to applications, user communities, and decision-makers, The Forecasters’ Handbook provides a template for finding much needed solutions to critical issues such as building resilience to weather hazards and climate change in West Africa.

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