  The superconducting upper critical field $H_{c2}(T)$ of a two dimensional BCS
superconductor is calculated in the vicinity of a van-Hove singularity. The
zero temperature upper critical field is strongly enhanced at weak coupling
when the Fermi contour coincides with van-Hove points, scaling as $H_{c2}(0)
\propto T_c^{\sqrt{2}}$ compared to the usual result $H_{c2}(0) \propto
T_c^{2}$. The result can be interpreted in terms of the non-Fermi liquid decay
of normal state pair correlations in the vicinity of a van-Hove point.
