Obviously the wrong kind of wet snow / sleet / rain / snow pellets on
the tracks

A radio station called TalkSPORT the other morning had a massive rant
about standards of driving in light to moderate snow showers, or slushy
stuff that central london tends to get, unless the temp is really below
freezing. If there was any truth to what i heard, probably just as
well, a big snow event did not occur today in London