The weather forecast will be the major factor deciding the runways to be used. A “TTF METAR” is the best and most accurate guide and is normally accurate for three hours. So how do you work this out, simple google Metar yssy eg
https://en.allmetsat.com/metar-taf/a....php?icao=YSSY
METAR: YSSY 180500Z 15009KT 9999 VCSH FEW012 SCT020 BKN070 20/16 Q1014
That indicates a southerly so it’s likely 16 will be in use. There is also a TAF which has a longer outlook, a TAF is a Terminal Area Forecast and currently that indicates the wind will swing to a west to nor westerly at around 10pm tonight which would see 34 in use.
http://www.bom.gov.au/aviation/data/education/ttf.pdf Has moreinfo