pcolor video for loop with mask

Hi,

I'm trying to create a video time series of some map data using pcolor defined by some colormap and a black mask. The data I'm using (ex: water level) is binned by domains A, B, and C that represent different areas of the map with matrix coordinates X and Y. X and Y are not evenly spaced vectors so I can't use imagesc, which I would prefer to do but contourf might also work. I've set up a double for loop with the following code that includes VideoWriter:

aviobj = VideoWriter( strcat( 'Output\Videos', 'water_level', '.avi' ) );
aviobj.FrameRate = 6;

open( aviobj );

hFig = figure( 'Visible', 'Off' );
for j = 1:size( s.time.mapts );

    cla;
    hold on;

    ax1 = gca;

    for i = 1:length(domain);

    maximum( i, 1 ) = max( max( max( s.(domain{ i, 1 }).wlvl ) ) );
    minimum( i, 1 ) = min( min( min( s.(domain{ i, 1 }).wlvl) ) ) );

    mini = min( minimum );

        h1 = pcolor( s.(domain{ i, 1 }).xcord, s.(domain{ i, 1 }).ycord, ...
            squeeze( s.(domain{ i, 1 }).wlvl( :, :, j ) ) );
        shading interp;

        h2 = pcolor( squeeze( s.(domain{ i, 1 }).mxcord( :, :, j ) ), ...
            squeeze( s.(domain{ i, 1 }).mycord( :, :, j ) ), ...
            squeeze( s.(domain{ i, 1 }).mask( :, :, j ) ) );
        shading interp;

        set( h2, 'alphadata', squeeze( s.(domain{ i, 1 }).mask ), ...
            'alphadatamapping', 'none', 'facealpha', 'flat', ...
            'facecolor', 'black' );

    end

    caxis( [ mini maxi( k-4, 1 ) ] );
    cbx = colorbar( 'Location', 'SouthOutside' );
        set( cbx, 'NextPlot', 'replaceChildren' );
    colormap( squeeze( cmap( 1:(end-1), :, k-4 ) ) );

    set( ax1, 'XLim', [ 200000 340000 ], 'XTick', (200000:20000:340000), ...
        'XTickLabel', (200:20:340), ...
        'YLim', [ 50000 140000 ], 'YTick', (50000:30000:140000), ...
        'YTickLabel', (50:30:140), 'CLim', [ mini maxi( k-4, 1 ) ], ...
        'NextPlot', 'replaceChildren' );

    xlabel( ax1, 'X (km)' );
    ylabel( ax1, 'Y (km)' );
    xlabel( cbx, strcat( titlestr{ k-4, 1 }, unitsstr{ k-4, 1 } ) ); 

    box on;
    title( { strcat( titlestr{ k-4, 1 }, ' for Medium Flow: 7,000 cms' ); ...
        'July 31 - Sept. 1, 2005 (dt = 2 hrs.)' } );

    img = hardcopy( hFig, '-dzbuffer', '-r0' );
    writeVideo( aviobj, im2frame(img) );

    delete( cbx );

end

close(aviobj);

clear aviobj hFig

The problem is that only the last domain gets a black mask applied using the alphadatamapping properties. I've also tried just applying this code for the h1 pcolor plot with the same result. Alternatively, I tried adding black to the end of the colormap and specifying caxes, which works except that black ends up showing up the colorbar. I don't want that. The other thing I tried was to generate another invisible axes (ax2) and plot the mask overtop the data using NaNs for anything not masked but that also seemed not to work. Is there a simple way of applying a mask for loop to pcolor or preferably imagesc-like matrix coordinate data for all three areas of the map? FYI, the k index referes to the property being mapped (i.e. water level).

Thanks