Everyone’s opinion of perfection is a bit different but we won’t let that get in the way of our quest to find which part of Australia has the best weather. My study identified Rockhampton in Queensland as having the best climate. Who would have thought… It’s the beef capital of Australia and the cows were really onto something. Let’s look into how we came to this conclusion.
Through some research and a bit of personal preference I have selected the below criteria:
- Humidity (Dew point of 18°C or less)
- Temperature (18°C – 35°C)
- Cloud (Mostly blue skies – 4/8 oktas or less)
- Wind (less than 19 km/h or 10 knots)
You can read more about the logic behind the selection of this criteria here.
Spoiler alert! There are surprisingly few perfect days in Australia based on the above criteria which came as a bit of a shock to me. We might need to tweak our criteria a bit but we will get to that. If you want to have a bit of fun yourself playing with the criteria I will link my number crunching excel at the end so you can play with your own criteria.
Apologies now for all the tables, I needed them to get to the bottom of why perfect days were so few and far between. Fear not though, if you want a fast way through this article then skip over the “What happens if we Tweak the criteria” section and jump straight to the conclusion. Happy reading!
The Method – A Different approach for finding Perfection
Traditional weather metrics use maximums, minimums and averages which aren’t always representative of what’s happening on a daily basis. Maximums and minimums are often random extremes and averages are always in the middle and influenced by those extremes.
We are trying a different approach where we look at each day over a 3 year period (2019 – 2021) and see how many days meet our selected criteria.
For our dataset we will use Aviation weather data (METAR’s) taken from airports around Australia. In terms of data it doesn’t get much better as these observations are taken every 30 minutes in a highly standardised format. We can get our hands on the data thanks to Iowa State University who archive the data and make it available for free. Big thanks to them!
We are only focus on daytime temperatures at 09:00, 12:00 and 15:00 because these are the times we are most likely out there enjoying our day.
Our Locations around Australia
Almost all the locations are on the coast of Australia where more than 80% of the population live. I have tried to spread them out to no more than 1000 km of Latitude.
In hindsight, some more inland locations may have had been good to find less humid, cloudy and windy weather. For example Charlieville QLD (YBCV) or Meekatharra WA (YMEK) would have been good options.
You might notice there a more locations selected on the east coast than the west coast. Sorry, it was probably driven by my subconscious expectation to find paradise on the same side of Australia that I grew up on.
Most of the locations are at near sea level except for Canberra (578 m) and Alice Springs (545 m). This matters because elevation has an impact on temperature just as latitude does.
The Results – The odds of a Perfect day
Finding a perfect day in Australia based on the aforementioned criteria was a lot more difficult than I expected (Dew point of 18°C or less, Temperature 18°C – 35°C, Cloud 4 oktas or less, Wind less than 19 km/h or 10 knots). On deeper analysis of this, the root cause is that Australia is quite often a cloudy and windy place.
Perfect All year around
Based on the full criteria, Rockhampton is our winner with a Perfect day coming around a little more 17% of the time (around 1 in 7 days). Second place goes to Learmonth with 15% which is on a similar latitude to Rockhampton. Alice Springs takes 3rd place with a perfect day 10% of the time.
Filtering the data by year and not a lot changed other than Rockhampton winning 2021 and 2019, and Learmonth winning 2020.
If you are happy with partial perfection then our odds go up significantly, especially in places like Hobart, where there is high variability in the weather.
Perfect in the Summer
Focusing just on the Summer months (Dec, Jan, Feb), Canberra takes the trophy with a perfect day 12% of the time.
Adelaide and Merimbula get a distant 2nd and 3rd place with a perfect day 6% of the time.
Rockhamption our winner overall is still holding on with a Perfect day 4% of the time, tied with Melbourne.
Hobart comes in last with a perfect day never due to combinations of cold, wind and cloud.
Not surprising, the top end of Australia is a complete write-off due to the humidity.
Perfect in the Winter
Come winter (Jun, Jul, Aug) the north of Australia becomes livable as humidity drops. Learmonth takes the lead with 31% followed closely by a new contender, Broome in 2nd place at 26%. Rockhampton is still in the game holding onto 3rd at 19%.
Darwin has come onto the map to take 4th place with 16%. Alice springs has fallen from grace with only 6% of perfect days. From examining the data this is due to cold days which are common in dryer climates, especially when they are at elevation.
The highest variability can be seen in Taree, meaning that it’s 132 times more likely to be nice at least once a day than it is to be nice all day. This is driven by the frequent onset of cold weather, and less commonly cloud and wind.
Perfect in Spring and Autumn
Not surprising, the winners here are the same as we saw in the overall results, Rockhampton, Learmonth and Alice Springs. This 6 month period in Spring and Autumn is when they pick up a lot of their momentum. You won’t see a huge amount of variation during the day at this latitude (-23°S).
A lot of unpredictable weather is coming out of the Southern Oceans so we see more variation during the day around the south west corner of Australia (-34°S) and south east end with Hobart (-42°S).
What happens when we Tweak the Criteria
Let’s take a look at some different scenarios here to see what happens. We will lower the minimum temperature, increase our tolerance to humidity and disregard cloud and wind.
More Tolerant for Cold (Reduce Min Temp from 18°C to 15°C)
This scenario does not have a big impact on our winners, only upping their odds of their perfect day by 2-5%.
The extra 3°C leeway definitely helps the east coast locations, Coffs Harbour, Brisbane, Taree, Merimbula and even Sydney get a bump of up to 50% on their Perfect days.
On the west coast there is only a change of 1-2%, I would have expected more. The north of Australia is almost unchanged as it doesn’t get cold up there anyway.
More Tolerant for Humidity (Increase Max Dew point from 18°C to 21°C)
By adding another 3 degrees of Dew point we are moving into the territory of what a lot of people might find uncomfortable. (explained here in the section on humidity)
This scenario only benefits the tropical locations of Darwin, Cairns and Mackay by a bit over 50% but still keep our leaders firmly in place.
There is little to no impact on the west coast which is predominately dryer.
Disregard the Wind
This scenario is a game changer for Western Australia and probably the most exciting change in variables, breathing hope back into the idea that Australia has the perfect climate.
To the results, Learmouth takes 1st place on the leaderboard with 45% of days being perfect followed, by Alice Springs in 2nd place with 38% with Perth taking 3rd place at 37% , followed by Geraldton at 35% and Broom at 31%. Rockhampton still leads the east coast at 30%.
It is mind blowing what a factor wind plays – most locations across the board improve their score between 3-10 times on the east coast and up to 35 times on the west coast. Take Sydney for example jumping from just 3% to 23% on this one factor, or Geraldton going from 1% to 35%.
From these results it is clear how windy Australia is. Our initial wind value of 19km/h or 10 knots or less is still a significant breeze and borderlines comfortable for a day at the beach.
Disregard Wind and Cloud
This scenario is actually what most people pay attention to when they look for the perfect climate, they only take temperature and humidity into consideration.
doesn’t alter our original Leader board but it dramatically affect how often the east coast and southern locations see perfect days. As can be seen from the data, most east coast and southern locations double their perfect days.
For context, Albany is our most cloudy location followed by Hobart, Melbourne, Brisbane and Cairns being completely cloud free 5-20% of the time. Our least cloudy locations are Learmonth, Alice Springs Geraldton and Broome being completely free of cloud 50-80% of the time.
Combining all of the Scenarios
In this scenario we are going to set Min Temp to 15°C, Max Dew point to 21°C and ignore the wind and clouds.
We finally get a new leaderboard, well sort of – Rockhampton manages to hold onto 3rd place with perfect days 82% of the time.
In 1st place is Coffs Harbour with a staggering 85% of the days being perfect or 95% if you are happy with a partially perfect day.
2nd place goes to Brisbane with perfect days 83% of the time or partially perfect days 91% of the time. Even Sydney manages to pull off a perfect day 73% of the time trailing Geraldton’s 77%.
Even Melbourne and Tasmania manage to give the appearance of being livable with the score of 42% and 34% respectively. Lies, Damn Lies and statistics….
Based on the full criteria, Rockhampton Queensland is our winner with second place goes to Learmonth Western Australia. Alice Springs in the Northern Territory takes 3rd place. These locations are incidentally all around the same Latitude.
From this little exercise in statistics we learned that Australia is windy, at least at the airports, and Western Australia is the most windy of all. The east coast is more cloudy than the west coast, especially around Melbourne, Hobart, Brisbane and Cairns.
Melbourne and Hobart are miserable most of the time, regardless of how you tweak the weather criteria. Perth, Canberra and Adelaide are very nice in the Summer. Broome, Darwin and Learmonth are lovely in the winter. Cairns and Mackay contrary to popular belief are not that great in the Winter mostly due to the cloud.
In hindsight I would be inclined to add a few more inland locations and be a bit more relaxed with the weather criteria (Min Temp of 15, Max Dew point of 21, Max wind to 15 knots). With this scenario it does not change the outcome but just gives us a perfect day more often. (Click on the image to see the results)
Here is the link to the excel (34 Mb) if you want to have a tinker yourself. There are also lots of tabs allowing you to dig into the details. Just a word of warning, the excel has about 850,000 formulas in it so it takes 20 seconds to 1 minute to process when you change the variables.