The study of the wind pattern around Sri Lanka is meaningful [6] because wind is the key factor of the atmosphere. However, observed surface and upper air wind data are sparse for the area [7, 2]. We modified the model developed by the National Observatory of Greece which predicted three-dimensional wind fields for the island of Sri Lanka at fifty levels, different heights, from the surface layer [1, 4]. The mass consistent law and three-dimensional variational function were solved subject to the Lagrange-multiplier method [3, 4]. The contour map indicates the behavior of the wind according to the model predictions. These maps illustrate the wind vector for any location on the island, even if surface wind stations are not present. We have selected the month of January for this discussion because it represents the North-East monsoon periods and affects the island strongly. Colombo upper air wind measurements and other atmospheric characteristics were used to simulate the model. High speed winds were captured at the summit of mountains and various wind  speeds were reported in mountain gaps and valleys. The quantitative comparison with observed wind speed has proven the model to be practical (Table 1). The north of the island has wind with low variations and the lee-side is over-estimated in the model. However, we did not account for sea breeze and mountain effects.

wind speed, mass consistent model, wind direction, simulation, wind maps.