Hottest spring on record for Sydney and Perth
Sydney maxima averaged 24.7°C for the season, making it the warmest spring in terms of daytime maximum temperatures on record (records go back to the 1850s). September showed the warmest anomaly. Four days above 30°C were recorded in this month which is more than the entirety of last summer, bringing the September 2023 average maxima to nearly four degrees above the long-term average.
On the other side of the country, Perth also recorded the warmest spring on record in terms of maxima, averaging 26.2°C. Perth's current station only dates back to 1993 but using nearby stations the record can be extended back to the 1920s. November was the hottest month for the western capital, coming in at 30.3°C, nearly four degrees above the long-term average and also the hottest November in terms of minima and maxima on record.
All Australian capital cities except Adelaide and Canberra were warmer than long-term averages in spring.
Image: Maximum temperature deciles for Australia over Spring 2023, showing large parts of the country in the warmest 10% of records.
The season was a two-sided tale in terms of rainfall over the east of the country, with the first two months being dry, typical of an El Niño spring. Moving into November, though key El Niño signatures, such as sea surface temperatures in the central tropical Pacific, remained above El Niño thresholds, the climatic influence of El Niño—like so much in life—is relative. With sea surface temperatures also above average over the western Pacific near Australia, the mechanisms by which El Niño often reduces rainfall over eastern Australia were dampened, aided by other effects such as that documented here.
Image: Animation of observed rainfall deciles over Australia during September, October and November, 2023, showing a dry beginning to spring, followed by a wet end in many areas over the east.
Though rainfall totals for November were above average for Canberra, Sydney, Brisbane and Adelaide, at least one of previous very wet years (2021 or 2022) were wetter.
Perth was dry over the entire spring season with frequent outbursts of hot and very dry easterly winds.