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This work investigates six static stability measures a over West Africa Using National Center for Environmental Prediction (NCEP) and National Center for Atmospheric Research (NCAR) reanalysis in summer (June to September JJAS) for the period 1979-2005 the mean vertical distribution of the stability measures for different climatic zones over West Africa were computed at different tropospheric layers between 1000 and 70 hPa Five of the six stability measures considered here show a decrease in the mean troposphere by a factor of about three and seven from 925 hPa to 300 hPa This contributes to identify the mean features of the vertical structure of the West Africa troposphere circulation An Empirical Orthogonal Function ( EOF) analysis reveals that the JJAS stability measures variability is almost entirely controlled by one entirely positive EOF The first 2 EOFs represent more than 90% of the total variance and are sufficient to describe the spatial variability of the summer mean stability measure The relationship of the stability measure field to the convection represented by Outgoing Longwave Radiation (OLR) field was investigated by means of a Canonical Correlation Analysis (CCA) The correlations are stronger in areas where the first and second CCA pair of sigma and OLR have correlations of 72% and 65% respectively The first CCA pair mostly determine the arid and semi-and area whereas the second is related to the Guinea coast and wet equatorial region Crown Copyright (C) 2010 Published by Elsevier B V All rights reserved