There is a great demand to improve predictions of high‐impact weather across the African continent. This is because of the high frequency of intense convective storms that often produce severe flooding, strong winds and lightning, combined with the vulnerability of people, infrastructure and businesses to such hazards. The skill of numerical weather prediction over Africa is still low, even for lead times of less than 24 hours. Therefore, there is a particular need to deliver nowcasting of events as they occur. However, there remains a widespread lack of provision of nowcasting across Africa and virtually no use of automated nowcasting systems or tools. This limits the ability of national meteorological services to issue warnings and therefore potentially prevent the loss of life and significant financial losses. Coverage by meteorological radars is still very limited, but geostationary satellites provide regular high resolution data of the often large and long‐lived storms. As such, there is an opportunity to improve satellite‐based nowcasting capability in Africa. Work being undertaken as part of the Global Challenges Research Fund African SWIFT (Science for Weather Information and Forecasting Techniques) project is starting to improve the nowcasting of African convective systems and so the ability to provide timely warnings of extreme weather providing a wide range of benefits.

The transition periods in Ghana are quite interesting because of the hazards they create to the general public and especially the aviation industry. Strong winds accompany rain storms to rip off roofs of buildings. Dust haze will reduce visibility and affect activities of flight operations. Flight routes and destinations will have to be changed for safety measures. Meteorologists in Ghana have studied the synoptic features that trigger these activities. These features include the ITB (Inter Tropical Boundary), the Equatorial Trough and the nature of airmass affecting the West African sub region. Weather Transition Periods in GhanaMichael Padi* Ghana Meteorological Agency, Airport-Accra, Ghana winds that mostly affect the country are of continental in nature and northerly, mostly north easterlies. The direction from which the surface wind is blowing at that time determines the strength or intensity of the hazy condition. It defines the transparency of the atmosphere and it has been realized that when the north easterlies affect the country, visibility reduces drastically but when the airmass is directly northerly, though the atmosphere use to be quite dry but not so dusty as compared to the former.Evidence from satellites, GoogleEarth reveals that the nature of the surface over Niger, which is directly northeast of Ghana, looks quite sandy while directly north of the country, which is Mali, looks a little bit rocky. For these reasons, winds originating or tracking Niger looks dustier than those from Mali.The above listed weather conditions (major rainy season, the minor rainy season and the little dry season) do not apply to the entire country but depends on the geographical location and the season. They all occur simultaneously within a year, so weather forecasting for the country has been based on certain local elements in order to arrive at a very high accuracy.The major technique is the location of the Inter Tropical Boundary (ITB) over the West African sub region for which Ghanaian Weather Forecasters and Meteorologists devised in making predictions easier for the country. Because of the geographical location of the country, it is either affected by a maritime air mass or a continental air mass or both at the same time. This led to the exploration of the ITB, a location on the surface of the earth believed to be the boundary or a position where both dry and moist air masses converge on the West African sub region. Experimentally, the ITB has also been realized to coincide with areas on the surface which has dew point temperature of 15°C.Surface weather charts from ECMWF and NOAA had been the products used by Ghanaian meteorologists most of the time in making their weather predictions. The products have been very helpful and are

This study examines the recent changes in extreme rainfall events over Accra, Ghana. For this study, an extreme rainfall event is defined as a day with rainfall equal to or exceeding the 1980-2019 95 th percentile. Knowing extreme rainfall events help to identify the years with the likelihood of rainfall-related disasters in Accra. In addition, it helps to identify the years with the likelihood of drought or severe dryness which are critical for the livelihoods and economic activities of the people. The study used rainfall data from rain gauge for Accra and satellite-derived winds at the 850 hPa level over southern Ghana from 1980 to 2019. It compares these climatic parameters for both pre-2000 and post-2000 to find out the changes that have occurred throughout the study period. Results show that the frequency and magnitude of extreme rainfall have generally increased during the post-2000 period than during the pre-2000 period, causing increases in mortalities and damages to properties. Seasonally, extreme rainfall events were most intense in July during the pre-2000 period but have changed to June during the post-2000 period. Notably, more intense rainfall events have also occurred during post-2000 winter than pre-2000 winter, consistent with increased warming in the study area. Monthly mean meridional winds at the 850 hPa level were stronger (weaker) in the northerly (southerly) direction during the pre-2000 period but have changed to be stronger (weaker) in the southerly (northerly) direction during the post-2000 period.

If adequate measures are not taken to protect the water bodies in Ghana, the rivers will dry up and those left will be highly polluted and the country will have to import drinking water from the neighbouring countries and from abroad for human consumption. Also, lots of lives and property would be lost through flooding in most cities in every rainy season if certain habits like building on water ways and dumping of rubbish into drains are not discouraged.