The BOM weather station at Cairns Aero is now on the verge of reporting 13 straight dry days to end 2017. While there have been some fleeting sprinkles around the suburbs these have not been enough to trouble the Cairns City scorer.
In context: December average = 178mm. December 2017 = 26.8. This is how the seasonality works:
What it looks like in a longer term perspective with an annual moving average:
Meanwhile, in the northern hemisphere: Typhoon Tembin
It’s an interesting situation and consistent with the most recent BOM Weekly Tropical Climate Note due to be updated again this week after a festive break.
Update at Weekly Tropical Climate Note:
Australian monsoon onset unlikely in next week
While the monsoon trough briefly influenced the north Western Australia coast in association with tropical cyclone Hilda, northern Australia is yet to experience broadscale monsoonal flow this wet season. By convention, the Australian monsoon onset date occurs when the onset is observed at Darwin. Therefore, by this definition, the Australian monsoon onset has yet to occur—the last time the onset date was this late was during the 2011–12 wet season.
One factor contributing to the delayed start of the Australian monsoon is the continuing tropical activity in the northern hemisphere. A late-season near-equatorial trough persists in the northern hemisphere, extending from a developing low near the Philippines to another weaker tropical low in the Bay of Bengal. This trough lessens the likelihood of monsoonal flow developing in the Australian region, by deflecting energy associated with cross-equatorial flow from the South China Sea. This flow from the South China Sea ideally would energise a southern hemisphere monsoon trough and thereby assist in initiating the northern Australian monsoon onset.
The tropical depression near the Philippines may reach tropical cyclone strength in the next few days as it moves towards Vietnam. For tropical cyclone information in this region please see the Japan Meteorological Agency webpage here.