We have 2 nights in Katoomba in mid September after visiting Sydney. I just realized that mountain temps might be cooler. What should we expect and what should we bring to wear?

Expect cool/cold early & late & take layers.

A shower proof wind jacket may be useful too. Our early Spring weather, probably like yours, can be unpredictable.

In Katoomba, the summer average temperature around 22°C at daytime and night 13 to 19°C, winter daytime temperature 10 to 11°C and night -1°C, have a nice trip in the Blue Mountains.

The Blue Mountains generally has a reputation for snow in winter, however, despite the cool temperatures there are only around 5 snow days per year in the upper mountains.

It is extremely rare to see snow below Lawson. It is not unusual to see white blankets of frost covering the ground in the early morning hours.

Of an evening, thick coverings of ice can form on car windscreens. The crisp cool air of winter makes the Blue Mountains an ideal location for Yulefest. Cosy log fires can be found in many fine establishments.