  We study Coulomb blockade effects in the thermodynamic quantities of a weakly
disordered metallic grain coupled to a metallic lead by a tunneling contact
with a large conductance $g_T$. We consider the case of broken time-reversal
symmetry and obtain expressions for both the {\em ensemble averaged} amplitude
of the Coulomb blockade oscillations of the thermodynamic potential and the
correlator of its {\em mesoscopic fluctuations} for a finite mean level spacing
$\delta$ in the grain. We develop a novel method which allows for an exact
evaluation of the functional integral arising from disorder averaging. The
results and the method are applicable in the temperature range $\delta \ll T
\ll E_C$.
