This paper describes the experience gained while parallelizing the glo
bal medium range weather forecasting application called T80 on a PARAM
machine based on a distributed memory parallel architecture. The T80
code employs the spectral method for horizontal directions and finite
differencing in the vertical direction and time marching. The parallel
implementation takes care of the easy portability of parallel code ac
ross various platforms and environments. The parallel code is optimize
d using i860 based assembly routines. The validation of the parallel c
ode has been accomplished by comparing the parallel T80 results with t
hose of the Gray for 2(nd) February 1993 initial data.