Wet season is always an interesting time for gardeners, but this year, after a rather benign start, it's suddenly become quite a challenging period for both plants and gardeners alike. Let's see how things changed.
The Story of January 2025: From Dry Heat To A Deluge
January 2025 was a month of extremes. For most of the month, we experienced relentlessly hot, humid and dry conditions, with daytime highs running about 2°C above the long-term average. While that may not seem like a significant increase, over a month-long period, it makes a noticeable difference, amplifying the stress on the garden and the discomfort of the gardener. The high humidity made those temperatures feel closer to 40°C on some days, making even simple gardening tasks a challenge.
The total rainfall for January was a mere 148 mm - less than half the historical average recorded since 1941. The primary reason? The delayed arrival of the monsoon trough.
This image shows some of the global rainfall daily averages for the months of January and July. The monsoon trough is usually positioned over northern Australia in the southern summer month of January (as shown of the left), and then moves northward to sit along the equator during our southern winter.
It is the monsoon trough that brings areas of low pressure and sustained heavy rainfall. This happens during what we refer to as "the wet season". The beginning of a wet season is variable, but it usually happens during January.
When The Rains Came
On the very last day of January, after weeks of oppressive heat and inadequate rainfall, Townsville and its surrounding areas were suddenly hit in the afternoon and evening with a staggering 280 to 300 mm of rain, and then the deluge continued the next day with another 260 to 280 mm (recorded at the Townsville airport in the city). That's a lot of rain - 21 to 22 inches in 48 hours.
An area of low pressure had converged over Townsville and its surrounds and remained there for the following week. The downpours were relentless. Here in my outlying rural suburb, we received almost 500 mm (almost 20 inches) in that same period.
A Year's Worth Of Rainfall In Just Five Weeks
To put things into perspective, Townsville's annual average rainfall is 1137 mm. With 1139 mm recorded up to the end of Week 5, the city has already exceeded its yearly average just five weeks into the year.
This milestone comes after a record-breaking December 2024, when Townsville Airport (in the inner city) set a new rainfall record with 487 mm, bringing the three-month total to a staggering 1626mm!
In the days leading up to this torrential rain, at the start of Week 5, my garden was already enjoying a respite from the heat, with three days of light showers keeping the plants fresh. Blooms were adorned with raindrops that lingered all day, creating a scene I hadn't witnessed in over a year. A gentle stream trickled down our driveway, and the wallabies revelled in the new abundance of greenery.
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Despite the damp conditions, I was still able to get outside between showers to tackle the ever-persistent pests - tiny bright green grasshoppers and caterpillars that were feasting on many of the plants; and a stubborn infestation of mealybugs in the shade house and pergola gardens.
Seasons: Late-Summer & Wet Season
Daytime Temps: 25°C - 30°C
Night Time Temps: 21°C - 24°C
Humidity Levels: between 90% & 100%
Hours of daylight: 13 hours, but there was almost constant cloud cover from horizon to horizon
Rainfall: 482 mm (18 inches)
The month of February began on the final day of Week 5, so Week 6 covers the first week of February. Gardening chores were put on hold this past week, as it's been raining almost constantly, sometimes quite heavily. Everything is sodden underfoot with some areas of the garden slightly under water and very slippery. My Week 6 entry is therefore mostly about the weather event that has impacted the region of Northern Queensland where I live.
When A Common Weather System Turns Extreme
Northern Queensland, is no stranger to tropical weather, but this week has been nothing short of extraordinary. While no destructive cyclone made landfall, a series of unfavourable conditions transformed a relatively common weather system in to a record-breaking weather event. For some, it's been a catastrophic event, surpassing all expectations in terms of rainfall and impact.
A tropical low, which originally formed off the coast of Cairns (around 600 km to the north of my home city of Townsville) on January 28, has inundated the northern region with staggering amounts of rain. Some areas recorded nearly two metres of rainfall in just a few days. The event claimed two lives, with the potential for more rain in the forecast.
What Caused The Torrential Rain?
Tropical lows are a routine part of our northern Australian wet season, often seen as the early stages of cyclones before their winds reach destructive strength. While lows form multiple times a year, most do not raise major concerns. Typically, these systems bring moderate rain and are manageable withing the region's preparedness frameworks.
However, two critical factors intensified this particular system:
- Slow movement of the low. After forming, the tropical low drifted away from the coast for several days where it stalled, continuously drawing moisture from the warm ocean waters. When it turned and headed back inland, this sustained moisture influx resulted in torrential downpours days on end, overwhelming local drainage systems and causing widespread flooding.
- Unusually warm Coral Sea. The sea surface temperatures in the Coral Sea have been significantly warmer than usual. Warmer waters lead to increased evaporation, which in turn fuels heavy cloud formation and intense rainfall.
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| Photos taken around Townsville |
The Impact Of Record Rainfall
This past week has been one of the most challenging times for my city of Townsville and its surrounding communities, as relentless rainfall and severe flooding wreaked havoc across northern Queensland. A 735 km stretch of coastline from Cairns to Mackay has been impacted, with Townsville, Ingham and Cardwell among the worst hit by flash floods and overflowing waters.
Both Ingham (270 km north of Townsville) and Cardwell (320 km north) were completely cut off, with highways closed due to floodwaters. Residents faced power outages and a compromised water supply, forcing authorities to cut off access to drinking water. With roads impassable, grocery supplies dwindled rapidly, leaving communities struggling to secure essentials.
Townsville - the largest city in northern Queensland - is a sprawling city covering an area of almost 3,750 km2, and includes 98 suburbs. Normally, rainfall is inconsistent across the city. The inner city can be drenched while the outer suburbs remain dry. During this weather event, all suburbs received rain, but as usual, it varied across the city.
Many of the northwest suburbs recorded massive rainfall totals at the start of the week compared to the suburbs located on the outskirts to the south. The suburb of Rollingstone, 60 km northwest of the Townsville city centre, recorded a whopping 702 mm over the 24 hours to 9.00 am on February 2nd, while the Townsville Airport (in the inner city where the weather station is located) recorded 545 mm, and my suburb received around 486 mm over that same period of time.
This graphic shows the difference in rainfall totals across the Townsville local council area from 9.00 am on the 2nd of February to 9.00 am on the 3rd. The black box in the top left hand corner shows the 24 hour total for the northern suburb of Paluma, while the yellow box on the left shows the 24 hour total for my rural suburb on the southern outskirts. All the red dots in the centre indicate the varied totals for the inner city suburbs.
By Sunday, February 3rd, low-lying inner city suburbs, such as Rosslea, Oonoonba, Railway Estate and Stuart, were declared "black zone" areas and residents were told to evacuate. Police went door to door informing home owners that it was in their best interest to leave their home and go to the nearest emergency shelter. Small armies of support workers were there to provide everything from bedding and towels to pet food and counselling.
Suburbs located along the Ross River were also included in the "black zone" area as the river's water level rose quickly. Water levels in the city's Ross River Dam, which fed into Ross River, rose over the dam's 100% capacity and our local authority began releasing water through spillways to relieve pressure. This of course added to the already increased volume in the Ross River. Many residents in homes close to the swollen river began sandbagging their properties in an effort to keep out the rising water.
Townsville's Ongoing Flood Risk: Dam Levels, River Rises and More Rain To Come.
A contributing factor in the city's flooding has been the Ross River Dam.
The following graphic shows the level of our dam over this past week:
When the flooding peaked at the start of this week, Townsville came to a complete halt. Roads across the city were closed due to the rising water, cutting off entire suburbs. Shops shut their doors, unable to operate amid the chaos. Schools were closed. Bus services and the airport ceased operations.
By mid-week, the most intense rainfall had eased, allowing floodwaters to begin receding. However, with new lows developing, authorities remain on high alert for another potential surge.
With the wet season still ongoing, the big question remains - how much more rain will fall?
The February rainfall record for Townsville has already been broken, and we're only eight days into the month! 2025 is shaping up to be a year for the record books.
The latest radar and satellite imagery (8.45 pm on Saturday, February 8):
The monsoon trough still lies across Northern Queensland in an environment rich with tropical moisture, allowing the development of slow-moving heavy showers and severe thunderstorms. Significant rainfall is predicted to continue into next week.
A Rural Perspective: My Property's Experience
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| Photos from around my suburb at the start of the week |
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