Sydney has enjoyed a rare colder than average day with its second coldest sunny day for winter. A cold front moved through Sydney yesterday, bringing gusty westerly winds, but almost no immediate change in temperature. The effects of the cold front have been felt today, with a much colder airmass in place. Many Sydney residents would feel like they've done a trip to the Blue Mountains with the drop in temperatures and the very dry and crisp westerly winds. The relative humidity has been steadily dropping all day as the moist Sydney air gets pushed out to sea by the dry mountain air. The mercury has only been able to nudge 16.6 degrees in the city today, despite the stunning clear skies. This is the second coldest sunny day for winter, a meagre 0.3 degrees warmer than the coldest sunny day on 21st July. Western Sydney has been chillier with most suburbs only reaching 15 degrees. Meanwhile, the Blue Mountains have been even colder than Sydney with snow falling last night and early this morning. Blackheath was the first to report snow yesterday evening. Much of the Central Tablelands had snow, but most locations barely had a dusting. Wind chill has also been a factor in Sydney with much of the day feeling a couple of degrees colder than what the mercury would suggest. Tonight will be quite cold across the Sydney Basin, with light frost expected around Richmond and a risk elsewhere in the west. The city should have one its coldest nights of the year. Tomorrow will be fairly similar to today, although not quite as cold or as windy. On Thursday another cold front will move across, this time bringing more cloud and the chance of another cold and gusty day. From Friday, Sydneysiders who hate winter can breathe a sigh of relief with a warmer airmass pushing into New South Wales. Spring will take hold, meaning that there should only be the odd cool day after the upcoming beautiful weekend.