What factors dictate the direction of movement of a line of TS ?
I am specifically thinking of YSSY and YBBN. My guess would be that it is mainly a combination of surface wind and winds up a bit higher, say 5000ft , but I’d like to know if there are other major factors, anyone know?
Cheers

While this comes from the other side of the planet and may or may not be applicable to the specific meteorology of the Australian east coast, in the USA the 18,000 winds are called the “steering winds” of storm systems. More specifically, meteorologists will look at the 500 millibar upper air chart (the winds following the 500 millibar constant pressure surface, which varies around an average of 18,000 feet-“ish”). This shows a good representation of the general vorticity (“spin”) in the atmosphere, since at that point roughly half the atmosphere is above and below.

Thanks for the replies everyone. The above responses are along the lines of what I’m seeking in that I am picturing small coastal systems effecting the airfield rather than cold front storms or large depressions.
ie, If I can see a line of cells 10nm west of the field on my radar while I’m holding and the surface wind is westerly, the 10,000ft wind forecast as northerly.....does that generally mean a SE direction of travel?
I understand every situation is different etc, just seeking others ideas, experience.
Thanks again

Ha, good catch! Yes, that is what I meant.

Thanks Underfire,
great site