%     read grads field

lon=96; lat=48;

xydim=lon*lat; tdim=4400;

field=zeros(tdim,lon,lat);

infile = ['filename.grads'];


fid = fopen(infile,'r');

for t=1:tdim
    
   xin= fread(fid,xydim,'float');
   
   for i=1:lat; 
       
        field(t,:,i) = xin(lon*(i-1)+1:i*lon);
        
   end
   
end


% plot example
clf

contourf( squeeze(field(1,:,:))' ); colorbar