Dry season bushfire smoke layers in a hazy sunset - Darwin, NT, Australia - 9 May 2023
“THE WET” AND “THE DRY” IN THE NORTHERN AUSTRALIAN TROPICS
The Northern Tropics of Australia in the Darwin region are described as having only 2 seasons – the “wet season” (or simply “The Wet”)(broadly November to April) and the “dry season” (or simply “The Dry”) (May to October). There is no local designation of Spring, Summer, Autumn and Winter, although it should be noted that some ancient local indigenous calendars describe up to 8 seasons, categorised by not only weather but also flowering and fruiting of edible plants, appearance of migratory animals as food sources, river heights, etc.
While Europeans settled Darwin in the 1860s, indigenous Australians have occupied the area for at between 40,000 and 60,000 years.
In broad terms, the main differences between the Wet and the Dry relate to humidity levels, prevailing wind direction, and (as the names imply) rain, or the absence of rain.
Darwin has no frost, no snow and no hail.
Darwin is also largely flat and unelevated, with few locations exceeding 30 metres above sea level.
Darwin is located 12 degrees south of the equator, in the middle of the cyclone belt.
THE WET – NOVEMBER TO APRIL
During the Wet, temperatures range from a minimum of 27 – 28C overnight (sometimes not dropping below 30C) and 34 – 36C during the day. Humidity levels are in the range of 75 – 95%.
The prevailing monsoon wind direction is from the North West (i.e. from the Timor Sea), except during the frequent storms, which normally come from the South East.
Cyclones (the local name for a typhoon or hurricane) also form during the Wet as part of monsoon trough activity. The wind from a cyclone can come from any direction, depending on the relationship between the cyclone’s eye and the observer’s position.
Rainfall during the Wet approaches 2,000 mm; with the record for a 6 month Wet season period being 3,000 mm.
Sea temperature during the Wet is around 32C.
Towards the end of the wet season there are almost daily storms with strong winds from the south-east, generally late in the late afternoon. These storms are called “knock-em-downs” as they flatten the 2 metre tall native spear grass which covers all uncleared areas. The spear grass will eventually die off and a large proportion of it will burn in dry season grass fires. The spear grass seeds are a staple diet of many finches and parrots. The spear grass re-germinates when the first storms arrive in October or November.
THE DRY – MAY TO OCTOBER
During the Dry, temperatures range from a typical minimum of 20 - 21C overnight (on rare occasions dropping to 16C) and 30 -31C during the day. Humidity levels are in the range of 10 - 30%.
The prevailing wind direction is from the South East (i.e. from the direction of the Great Australian Desert); with an occasional light North West sea breeze rising in the late afternoon.
There is virtually no rain between April and October.
Because of the absence of rain, a high bushfire danger exists throughout the area during the Dry, with the highest risk occurring in August and September, before the next Wet season storms occur. During these months, the humidity is very low and the South East winds are at their strongest – up to 30 knots (around 55 km/hr).
Bushfire smoke blows out to sea and causes spectacular sunset effects.
Dry season bushfire smoke layers in a hazy sunset - Darwin, NT, Australia - 9 May 2023
“THE WET” AND “THE DRY” IN THE NORTHERN AUSTRALIAN TROPICS
The Northern Tropics of Australia in the Darwin region are described as having only 2 seasons – the “wet season” (or simply “The Wet”)(broadly November to April) and the “dry season” (or simply “The Dry”) (May to October). There is no local designation of Spring, Summer, Autumn and Winter, although it should be noted that some ancient local indigenous calendars describe up to 8 seasons, categorised by not only weather but also flowering and fruiting of edible plants, appearance of migratory animals as food sources, river heights, etc.
While Europeans settled Darwin in the 1860s, indigenous Australians have occupied the area for at between 40,000 and 60,000 years.
In broad terms, the main differences between the Wet and the Dry relate to humidity levels, prevailing wind direction, and (as the names imply) rain, or the absence of rain.
Darwin has no frost, no snow and no hail.
Darwin is also largely flat and unelevated, with few locations exceeding 30 metres above sea level.
Darwin is located 12 degrees south of the equator, in the middle of the cyclone belt.
THE WET – NOVEMBER TO APRIL
During the Wet, temperatures range from a minimum of 27 – 28C overnight (sometimes not dropping below 30C) and 34 – 36C during the day. Humidity levels are in the range of 75 – 95%.
The prevailing monsoon wind direction is from the North West (i.e. from the Timor Sea), except during the frequent storms, which normally come from the South East.
Cyclones (the local name for a typhoon or hurricane) also form during the Wet as part of monsoon trough activity. The wind from a cyclone can come from any direction, depending on the relationship between the cyclone’s eye and the observer’s position.
Rainfall during the Wet approaches 2,000 mm; with the record for a 6 month Wet season period being 3,000 mm.
Sea temperature during the Wet is around 32C.
Towards the end of the wet season there are almost daily storms with strong winds from the south-east, generally late in the late afternoon. These storms are called “knock-em-downs” as they flatten the 2 metre tall native spear grass which covers all uncleared areas. The spear grass will eventually die off and a large proportion of it will burn in dry season grass fires. The spear grass seeds are a staple diet of many finches and parrots. The spear grass re-germinates when the first storms arrive in October or November.
THE DRY – MAY TO OCTOBER
During the Dry, temperatures range from a typical minimum of 20 - 21C overnight (on rare occasions dropping to 16C) and 30 -31C during the day. Humidity levels are in the range of 10 - 30%.
The prevailing wind direction is from the South East (i.e. from the direction of the Great Australian Desert); with an occasional light North West sea breeze rising in the late afternoon.
There is virtually no rain between April and October.
Because of the absence of rain, a high bushfire danger exists throughout the area during the Dry, with the highest risk occurring in August and September, before the next Wet season storms occur. During these months, the humidity is very low and the South East winds are at their strongest – up to 30 knots (around 55 km/hr).
Bushfire smoke blows out to sea and causes spectacular sunset effects.