You could use the <A HREF="https://en.wikipedia.org/wiki/Bhattacharyya_distance">Bhattacharyya coefficient $w=e^{-d}$</A> $$d=\frac{1}{4} \ln \left [ \frac 1 4 \left( \frac{s^2}{m^2}+\frac{m^2}{s^2}+2\right ) \right ] +\frac{1}{4} \frac{(a-b)^{2}}{s^2+m^2}, $$ as the measure for the closeness of two Gaussian distributions (means $a,b$; variances $s^2$, $m^2$).