\begin{eqnarray}
    IF \ (q_{sat} < q_{air}) \ THEN \ (IF \ (T_a > 0) \ THEN \ toveg=TRUE, \ tosnow = FALSE ) \\
    IF \ (q_{sat} < q_{air}) \ THEN \ (IF \ (T_a < 0) \ THEN \ toveg= FALSE, \ tosnow=TRUE )  
\end{eqnarray}
