Creating a selective meshgrid

I am trying to create a meshgrid of lat/lon coordinates, but because the resolution of the points is so fine, my computer runs out of memory and MATLAB aborts the process (see below):

    nc=ncgeodataset(['CMC_reg_TMP_TGL_2_ps10km_',yyyymmdd,'00_P',...
        chhh,'.grib2']);

    nc.variables
    dirvar=nc.geovariable(nc.variables(2));
    dir=dirvar.data(1,:,:);
    g=dirvar.grid_interop(1,:,:);
    [glon,glat]=meshgrid(g.lon',g.lat);
    
    Out of memory. Type HELP MEMORY for your options.
    

My end goal is to be able to extract a smaller grid of points from this giant meshgrid, can anyone think of a way to bypass that and just create the meshgrid to the specifications I need. The lat/ lon boundaries are: Lat: 45.37 to 53.07, Lon: -108.73 to -93.98.

I am on MATLAB R2011b FYI.

[Matt J]

Why not just start with the smaller destination grid?