You have the distance to each cell as the following:
[x,y,z] = ndgrid(-1:1);
R = [z(:),y(:),x(:)];
R(14,:) = []; % since you do not consider the center cell (0,0,0)
C = 1:26; % this coordinates with the (x,y,z) position in R
Now you need to get a normalized wind vector:
wind = [100,10,0];
nwind = normalize(wind,'norm');
Then finally, find the minimum euclidean distance between nwind and R. There are several ways to do this, here is one:
edist = sqrt(sum((nwind-R).^2,2));
[~,ind] = min(edist);
nextCell = C(ind); % the next cell to move to
And the output is:
nextCell =
22
