First results from the extended Canadian middle atmosphere model are presented. The model extends from the surface to the middle thermosphere and includes relevant physical parameterizations. To simulate unresolved gravity waves a non-orographic gravity wave drag parameterization has also been implemented. Results from a two-year simulation are discussed and are shown to be in good qualitative agreement with upper atmosphere research satellite wind observations. The realistic features which are reproduced include the reversal of the mesospheric jets and the semiannual variation of the migrating diurnal tide in the low latitude mesosphere. ¿ 2000 American Geophysical Union