The lower Blue Mountains, such as Glenbrook experience a much warmer and more temperate climate than the upper Blue Mountains. Lower areas sit at altitudes around 160 to 450 metres, with typical winter averages near 16°C and summer averages reaching 29°C. Higher up, in towns like Katoomba and Mount Victoria (over 1000 metres), the climate is cooler and more variable, with winter averages around 5°C and summer averages close to 18°C. Temperatures generally decrease by about 2°C for every 300-metre increase in altitude. Rainfall also increases with elevation, with the upper mountains receiving roughly 1050 mm of rain per year making conditions wetter and mistier while the lower mountains average about 850 mm annually. Snow will occasionally fall in the upper Blue Mountains, but not often.
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