Australia's northernmost capital city Darwin has just sweated through its hottest May in reliable records for maximum temperatures, as well as one of its most humid despite no rain falling.

Darwin's maximum temperatures averaged 33.7°C this May, +1.6°C warmer than the long-term average for the site. This makes it the warmest May in 117 years of reliable records*, just warmer than previous title-holder in 2022 (averaging 33.6°C). 

Image: Maximum temperature deciles for May, showing they were the highest on record for Darwin and surrounding areas, with much of the Top End and eastern NT above average.

Temperatures ranged from a high of 35.1°C on Friday 10th and a low of 30.5°C on Tuesday 21st. Oddly enough, both of these days featured gusty east-southeasterly winds coming off the Australian continent. The difference between these two days was cloud-cover, with warm conditions in clear skies, and cooler conditions if its cloudy.

Minimum temperatures averaged 23.7°C, +1.5°C above average. While this seems warm (even hot by southerner's standards) this was only the 10th warmest May on record. Only one night fell below 20°C (19.1°C on Tuesday 21st), the common threshold beyond which locals add an extra blanket to the bed.

Darwin did not record a drop of rain during May, although that is fairly common. 24 out of the 78 Mays the current Darwin Airport site has been recording for have been completely dry, with a further eight recording 1mm or less.

Despite the dry, Darwin and much of the Northern Territory were more humid than normal during May. The map below shows specific humidity (akin to dew point temperature) anomalies during May. The large region in blue and purple reflect humidity being higher than normal.

Darwin and the NT is far from alone with this increased humidity, with locations near the equator from Africa to the central Pacific Ocean showing a similar pattern. This reflects how much warmer ocean and air temperatures were during May, and for the last 12 months, especially for the world's tropics.

Climate outlooks are suggesting Darwin will continue with a run of warmer than average temperatures each month during the dry season. However, if La Niña starts to develop, increasing cloud would be expected over the Top End later in the year, reducing temperatures closer to average.

*Note: Prior to 1907, records at Darwin's Post Office site are not considered always reliable as this was before weather measurment standards were enforced at the site.