Even in Poland in winter, there are very few occasions when a CAT III
ILS approach would be necessary.
Unfortunately there are quite a lot of diversions, however it's not wintertime when it's bad but in spring/autumn.
Plus remember that not all airlines train their crews to CAT III minima (for the
few times when it proves necessary), or have aircraft certified to those limits.
We could use some CAT III runways with 13 aircraft based in Poland (all a/c and flight deck crew qualified for CAT IIIb)...