We present our resonant X-ray diffraction work to study the antiferromagnetic spin canting perpendicular to the hexagonal planes of the archetypal type-I multiferroic YMnO₃. We find the x-ray diffraction spectral shape at the Mn L<sub>2,3</sub> edges change as a function of temperature below T<sub>N</sub> for this material. Using a combination of phenomenological arguments and computations using the DFT-based FDMNES code, we attribute the difference spectra to be a result of interference of scattered amplitudes from the canted magnetic dipole and higher-order magnetoelectric multipoles.