Rate hypothetical Sydney

Why do you think it would become colder if the mountain barrier between Sydney and the Australian desert were removed?

The ocean is cool, the desert is hot. Wouldn't a mountain range between the desert and the ocean increase the "effective distance" between the two? Meaning since Sydney is on the ocean side of the mountain range, it gets more "ocean weather" than it would were the mountain range not there?

A C from me - worse than the real Sydney.

C. Slight improvement over the real Sydney.

Another interesting hypothetical would be if the GDR's average elevation was a lot higher, i.e. to the scale of the European Alps or even the Andes. I'd imagine Sydney's climate would be wetter in summer (increased rainfall from easterly systems), drier in winter (less southwesterly rain) and warmer overall (increased foehn effect), though I'm not an expert so I might be wrong.

Wow, that's absolutely fucking even by your standards.

The reason Sydney even gets those hot record highs in the first place, is because of the downsloping winds that occur as a result of that very "mountain barrier". Any weather system/airmass that passes over the leeward side of the range, always becomes warmer and drier—no ifs, no buts, no maybes.

For instance, Penrith in Sydney's western suburbs recorded a prodigious 49° C; and this reading surpasses those even in the far west/outback of NSW (such as at Griffith), despite Penrith's coastal location—why? Because Griffith is windward to the prevailing westerlies, whereas Penrith is leeward.

Thought I sort of blew my fictional climate box, but glad that it was rather accurate. Though on a second thought, maybe the winter lows were too high (for the record lows)? I should've tweaked those down a notch a little. Lol. 

Anyway, about the last paragraph. When you wrote Penrith, I had Perth race into my mind -- Why is Perth so hot in the summer, also despite its coastal location and being on the windward side? I hope my question isn't . I understand that I may be missing something very crucial. And I know the subtropical ridge hangs around there in the summer, but I'm not sure if that solely heats things up there? Heck, same thing with Geraldton and other areas in the west, which seem to be hotter than the same latitude areas on the east coast (albeit nights are cooler, which makes sense because they lack humidity and clouds). What's the story behind the long, enviable hot summers in the Southwest WA anyway? 

Griffith is 300m higher than Penrith, no?

Föhn winds have large effect on records, yes, but they tend to have a very marginal effect on long term averages, and if anything just means the non-föhn days will be cooler in compensation.

I'm not very knowledgable on the inner workings of climatology and meteorology, and I don't claim or pretend to be either. I didn't claim Ethereal was wrong or that I was right. The whole comment was phrased as a question, just a suggestion.

I don't think it was as stupid of a suggestion as you're trying to make it out to be.

Ever noticed how Monaco and Nice's summer highs are a lot cooler than Marseilles and Montpellier? That's because the Alps effectively block Monaco and Nice off from the continent, locking them to the sea, whereas Montpellier and Marseille have a straight connection with Continental-European heatwaves. 

And looking at California, if you compare Santa Rosa with Concord, they're the same distance to the ocean, the difference being Santa Rosa has large mountains in the way between it and the California basin, whereas Concord doesn't. Santa Rosa averages 28'C highs in summer, Concord averages 30'C highs. Fairfield averages 32'C highs, still at a similar distance to the ocean, but with even less standing in the way of the California basin. 

It's bafflingly stupid to call me for suggesting something that's true in pretty much every single other part of the world.

^Small correction: Griffith's weather station is about 100 m higher than Penrith's, but that doesn't change a thing. Elevation means jack shit when we're talking 3+ °C temp differences, not to mention the fact that these elevations (lower hundreds) lay well below the Lifted Condensation Level (LCL), so lapse rates aren't particularly steep anyways.

Föhn winds only tend to affect certain days, in spikes. If the mountain barrier means that the rest of the days will be slightly colder, then it will obviously cancel out those few spikes of föhn heat. That's what you see in Norway. Their average monthly maximum temps are a lot warmer compared to their average monthly highs, than in Sweden.

Another problem with places that have tall mountain ranges right by the coast is that it isn't a coincidence that these places tend to have cold sea currents. If there are tall mountains by the coast, that typically means there will be a sharp elevation gradient in the sea. The steep elevation gradient doesn't typically simply stop at sea level. This makes it harder to identify how much the climate has to do with the mountains themselves vs how much they have to do with the corrolated cold water currents.

B-. Comfortable temps and good precip pattern, but still too warm in winter and much too cool in summer.