Iamas International Association of Meteorology and Atmospheric Sciences Association Symposia and Workshops

This study attempts to use a full spectrum of in-situ and remotely-sensed observations from meteorological satellite to examine the characteristics of the rainstorm that wreaked havoc on the stateofthe-art velodrome that stood out at the new National Stadium complex, Abuja, Nigeria, on Saturday, October, 2003, two hours to the closing ceremony of 8th All African Games and socio-economic implication of such damage. Deive and statistical analyses were used to illuminate the features involved in the study. With the aid of meteorological data and satellite imagery obtained from the Nigerian Meteorological office, it was observed that the storm cold clouds started as small in-situ cells of cumulonimbus clouds in the early hours of afternoon over the rocky high ground areas of the central part of Nigeria. Synoptically, features observed also from the NWP products( i.e. chart) show that the storm was initiated due to large thermal forcing over the area, down stream convergence of winds from the ocean observed both at 10m and 900m. Also the evidence of positive vorticity values due to cyclonic turning created around Abuja at 850Hpa chart may have influenced the storm. The storm was not a well defined organized and propagating type due to absence of African Easterly Jets (AEJ) during the period. Also, Inter-tropical discontinuity (ITD) or Inter-Tropical Convergence Zone (ITCZ) was already dropping southward with the area relatively stable. The main source of energy came from insolation, high reflective surfaces provided by the rocky hills that outcrops most of the region. The presence of these hills energized the system. The stadium is located at the windward or valley of two prominent hills (Zuma and Aso), hence the storm may have become more violent as it descends these hills. The maximum gustiness of the storm over the stadium was much greater than 60 knots. The absence of adequate outlets at the velodrome coupled with this gustiness may have been responsible for its destruction; as vortex was likely to have been created inside the velodrome. The rainstorm did not only destroyed property and facilities but also the velodrome of the newly-built stadium being the worst hit. The 8000 seating capacity bowl was shredded into pieces of rags by the heavy winds that accompanied the thunderstorm. Consequently, the multi-million naira worth of structure had to be repaired by the construction company at no cost to the nation.