We are ten days into winter, and temperatures are looking well above average in most southeastern parts of the country. In Melbourne, the long-term average maximum temperature for June is 14°C. That figure is calculated by averaging data from every June between 1855 and 2014. The cutoff year is 2014 because that is when the city's weather station moved from the northeastern corner of the CBD to Olympic Park.
Some Junes have been much colder than that, and some have been much warmer. If you were to line up every year from coldest to warmest, 14°C sits right in the middle. We often talk about climate as 'what we expect' and weather as 'what we actually get'. Melbourne is famous for how quickly its weather changes, as we usually experience many weather systems moving through. We have a hot desert to our northwest, tropical air to our northeast, cold air to our south, plus the Great Dividing Range and the influence of Port Phillip Bay. All these factors work together to ensure our weather can change rapidly.
However, it is not always the case. When a high pressure system sits over the Tasman Sea, between Australia and New Zealand, it directs a northerly airflow over Victoria. If the high is strong, it can block our usual weather systems from moving through or at least weaken them as they slide past. That is the type of pattern we have this week.
King's Birthday Monday Delight
It made King's Birthday Monday delightful for winter: light winds, sunshine, and a top of 17°C. Tuesday rose to 19°C, but it came with increasing winds, so it was not quite as pleasant. Wednesday was likely to also reach 19°C but was joined by some wet weather from a sliding cold front. Thursday is back down to 17°C and mostly dry, then the week ends with fog followed by lots of sunshine, and we are back up to 19°C.
We are running more than two degrees above the June long-term average, and that does not take into account the warmer than average days still to come this week and next week.
Weekend Cold Front
The weekend will see a stronger weather system move through. A stronger cold front arrives on Saturday, with showers developing and tending to steady rain on Saturday afternoon, slowly easing on Saturday night. If you need dry conditions for something on Saturday, it would be wise to move it to the morning as conditions deteriorate as the day progresses. The system is quick, and we are all dry on Sunday with bright sunshine and light winds, with an expected peak around 15°C, which is cooler but still above average.
Another strong system could arrive early to mid next week. The cold air from this is likely to linger back to our west through the first half of the week, delivering us further well above average days, even as rain sets in at times. However, if you are after a proper winter chill, and I know our snow resorts certainly are, one of those may arrive at the end of next week. That will be after a stretch of nearly two weeks where each and every day was above average.
