Fall in Perth brings a welcome break from the scorching summer. It’s honestly one of the best times to get out and explore the city or its coastline. You’ll get warm days, cooler nights, and average temperatures between about 14°C and 26°C (57°F to 79°F).
Most days stay sunny, but you’ll notice the occasional light shower and a bit of humidity. These little changes add a fresh feel to the landscape.
You’ll feel the shift as the weeks go by. Early fall still has enough warmth for afternoons at the beach or walks in the park.
By late fall, the evenings get chilly enough that you’ll want to grab a jacket. Rain picks up a bit compared to summer, but it usually doesn’t ruin plans for sightseeing or dinner outside.
If you know what to expect, planning’s a lot easier. Whether you’re hoping for a stroll through wildflower trails or a cozy night in the city, fall in Perth gives you a season that’s both relaxed and full of variety.
Overview of Fall Weather in Perth
Fall in Perth means the weather gradually cools and gets a little wetter after summer’s dry heat. You’ll notice the days getting shorter, milder temperatures, and a bit more cloud cover overhead.
Rain starts to show up more often, but the sun still puts in plenty of appearances.
Typical Fall Climate Patterns
During fall, Perth’s daily highs usually start around 85°F (29°C) in early March and drop to about 67°F (19°C) by late May. Nights cool off quickly, with lows settling in the mid-50s°F (12–14°C).
Rainfall picks up after the parched summer. You might only get a few showers in early fall, but by May, rain becomes a regular visitor. Humidity edges up a little, though Perth’s coastal setting keeps it from feeling sticky.
You’ll see a mix of sunny and partly cloudy days. Overcast skies become more common, rising from about 20% in March to nearly 30% by late May.
Winds calm down compared to those strong summer sea breezes, so the air feels gentler.
Key Weather Changes From Summer to Fall
The biggest change? The heat drops off. Summer highs in Perth often soar above 90°F (32°C), but by mid-fall, you’ll find afternoons in the low 70s°F (21–23°C).
This makes being outside a lot more comfortable.
Rainfall also stands out. Summer barely sees a drop, but fall marks the start of the wetter half of the year. By May, monthly rainfall averages hit about 90 mm (3.5 in), hinting that winter’s on the way.
Daylight slips away steadily. You lose almost an hour of sunlight each month. So, while summer evenings seem endless, fall evenings start to cool and darken much earlier.
Comparison to Other Seasons
Perth’s fall sits right between summer’s extremes and winter’s chill. Instead of summer’s heat and dryness, fall offers more moderate temperatures and the occasional rain.
You still get plenty of sunshine, but without that relentless summer sun.
Compared to winter, fall feels warmer and a bit drier. Winter brings the heaviest rain, loads of clouds, and cold nights. Fall acts as a bridge, letting you enjoy some warmth during the day without the long dry spells.
Spring’s a different story, with rising temps and less rain. Fall, on the other hand, cools things down and gets Perth ready for its wettest season.
Monthly Breakdown: March, April, and May
Autumn in Perth means temperatures cool off, daylight hours shrink, and rain becomes more frequent. The season moves from warm, dry March days to the cooler, wetter conditions of May.
March Weather Overview
March still hangs onto summer’s heat. Daytime highs average 29–30°C (85°F), with nights dropping to about 17°C (63°F).
Humidity starts to rise compared to February, but it’s still comfortable for outdoor activities.
Rainfall increases a bit, averaging 20–25 mm at Perth Airport, but most days stay dry. There’s still plenty of sunshine, so you’ll have lots of daylight for day trips or the beach.
Winds stay moderate, often offering a break from the heat. Evenings cool off, which makes eating outside much more pleasant.
March feels like a sweet spot—summer’s warmth with just a hint of autumn on the horizon.
April Weather Overview
By April, daytime highs drop to about 25–26°C (77–79°F), and nights cool down to around 13°C (55°F). The air feels crisp, especially during the mornings and evenings.
Rainfall picks up to around 40–50 mm, and you’ll notice more showers than in March. Humidity rises, but it rarely gets uncomfortable.
Cloudy days become more common, but sunshine still breaks through often.
Winds calm down a bit, and conditions are perfect for hiking or exploring inland. April really feels like the heart of autumn, where outdoor plans are still possible, but you’ll want to keep an umbrella handy.
May Weather Overview
May signals the real start of winter’s approach. Highs drop to 21–22°C (70–72°F), and lows hit about 10°C (50°F).
Mornings get colder, and evenings can feel downright chilly, so definitely bring an extra layer.
Rainfall jumps up, averaging 85–90 mm at Perth Airport, and wet days become more common. Humidity climbs, and clouds fill the sky more often.
Sunshine hours shrink, so you’ll have less daylight for adventures.
The rain brings out greener scenery, but you’ll need to plan for showers if you’re heading out. May’s definitely cooler and wetter than March or April, and you can tell winter’s just around the corner.
Temperature Trends During Fall
Fall in Perth sees the weather slide from summer’s heat to much milder, cooler days. Daytime highs drop steadily, nights get colder, and clouds start to roll in as winter nears.
Average Daytime Temperatures
Daytime temperatures in Perth during fall usually go from about 29°C (85°F) in March to around 19°C (67°F) in May. That’s a pretty clear cooling trend, typical of the city’s Mediterranean climate.
March afternoons can still feel hot, so you’ll probably stick to light clothes. By May, you’ll want a light jacket or sweater for the day.
Sunshine hours also drop as fall rolls on. March brings long, sunny days, but by May, you’ll see more clouds and about 20–30% of days are overcast.
This makes early fall better for the beach, while late fall feels more suited to walks inland.
Nighttime Temperature Variations
Nighttime temps drop even faster than daytime readings. March nights average around 16°C (61°F), but by May, you might see lows of about 10°C (50°F).
Evenings and early mornings start to feel much colder than the afternoons.
March nights are great for eating outside, but by late May, you’ll probably want something warmer to wear, especially near the coast where the breeze can make it even chillier.
Humidity creeps up as the season progresses. Nights in April and May can feel damp, a big change from the dry warmth of March.
This shift ties in with the winter rains that become more common after May.
Historical Temperature Data
Long-term climate records show Perth’s fall temperatures follow a predictable pattern. Average highs drop by about 10°C (18°F) from March to May, and average lows fall by about 6°C (11°F).
Thanks to its Mediterranean climate, Perth almost never gets extreme cold in fall. Frost isn’t a problem, and temperatures rarely dip below 5°C (41°F).
Weather data backs up the idea that fall is a transition period. Rainfall increases a bit, but the real wet weather waits for winter.
This makes fall a pretty stable season for planning outdoor activities, with predictable cooling and manageable weather.
Rainfall and Precipitation Patterns
Perth’s Mediterranean climate means early fall stays warm and dry, but things get wetter by late May. Rain doesn’t show up evenly, and both total precipitation and rainy days change a lot as fall goes on.
Monthly Rainfall Totals
Rainfall starts light in March and climbs steadily toward May. March usually sees about 15–20 mm of rain, making it one of the driest months.
April brings 35–40 mm, a sign that the season’s shifting.
By May, rain really ramps up. Expect 80–90 mm on average, more than four times what you’d see in March.
This jump signals Perth’s move toward its winter wet season.
The Perth Airport weather station reports that most rain comes from passing cold fronts. These fronts bring short, sometimes heavy bursts of rain.
Unlike summer’s thunderstorms, fall rain is more widespread and steady across the area.
Number of Rainy Days
Rainy days increase as fall goes on. March averages just 2–3 rainy days, so most days stay dry and sunny.
By April, you’ll get about 5–6 days with measurable rain.
In May, rainy days jump to 9–10 days. Not every day is wet, but showers become more frequent and can last for hours.
This matters if you’re planning outdoor activities, since May often brings more weather interruptions.
Rain doesn’t arrive all at once. You’ll notice a gradual increase in cloudy days as weeks pass, even if rain totals stay moderate.
May feels completely different from March’s dry warmth.
Transition Into the Wet Season
Fall bridges Perth’s hot, dry summer and its cool, wet winter. This shift becomes most obvious in late April and May, when weather systems from the Indian Ocean start to take over.
By now, soil moisture rises, and the landscape responds with new growth. Farmers count on these early rains to prep for winter crops.
Travelers will notice the end of Perth’s long dry stretch. As May goes on, you’ll want to be ready for cooler nights, higher humidity, and a much better chance of rain.
Humidity and Wind Conditions
In fall, Perth’s air feels different compared to the dry summer. Humidity creeps up, and steady winds play a big role in how the weather feels.
Average Humidity Levels
Humidity rises during fall as Perth moves away from its dry season. You’ll see moderate levels around 45% to 55% on average.
The air doesn’t feel as dry, especially in the mornings and evenings when it’s cooler.
By April, humidity edges up from March. May usually brings the biggest jump, as winter rain draws closer.
You might notice a mild dampness in the air, but it’s rarely uncomfortable—definitely not like tropical cities.
If you’re outside, this extra humidity can make mornings and nights feel chillier than you’d expect from the thermometer. The effect is strongest near the coast, where sea breezes bring in more moisture.
Wind Speed and Direction
Winds stay pretty steady in Perth during fall, but the patterns change a bit from summer. You’ll often get afternoon sea breezes from the southwest, which cool things down and keep the air fresh.
These breezes are strongest in March, then settle down as you move into April and May.
Average wind speeds sit between 12 to 18 km/h (7 to 11 mph). That’s enough to notice when you’re out for a walk or spending time outside.
Stronger gusts can show up during passing weather systems, especially late in the season.
Mornings usually bring lighter winds from the east. By afternoon, the reliable “Fremantle Doctor” sea breeze cools things off—even in early fall.
Impact on Daily Weather
Moderate humidity and steady winds really shape how fall feels in Perth. Humidity takes the dry edge off summer, and those winds keep the air from getting stale.
This balance usually creates pretty comfortable conditions if you’re heading outside. Breezy afternoons can make the temperature feel cooler than what the thermometer says.
When the wind dies down, though, the extra humidity can make the air feel a bit heavier, especially just before it rains. Travelers should expect these comfort levels to shift from day to day.
A light jacket comes in handy for evenings, since humidity and wind sometimes combine to add a bit of a chill, even if the daytime feels mild.
Additional Fall Weather Factors
If you’re planning to spend time outdoors in Perth during fall, don’t just look at temperature and rainfall. Daylight, sea conditions, and air clarity all matter too.
Daylight Hours and Sunlight
Daylight in Perth increases as fall moves toward summer. In September, you’ll get about 11.4 to 12.4 hours of daylight.
By November, that jumps to 13.2 to 14.1 hours. Longer evenings mean more time to enjoy the outdoors.
The number of sunny days goes up, too. September usually brings around 15 days of clear skies.
By November, you might see 22 sunny days. So, expect brighter days as fall goes on, though you’ll still get some cloudy spells here and there.
The sun angle gets stronger later in the season. UV levels rise, so you’ll want to grab some extra sun protection in late fall.
Sea Temperature and Coastal Effects
The Indian Ocean along Perth’s coast slowly warms up during fall. In September, the sea temperature hovers near 63°F (17°C).
By November, it climbs to about 68°F (20°C). This makes late fall a better time for swimming or water sports.
Seas usually calm down in fall, and the warmer water helps keep coastal air milder. Evenings at the beach can feel warmer than spots farther inland.
If you’re into fishing, sailing, or surfing, you’ll probably notice better conditions as the ocean warms up. Early fall sometimes brings cooler breezes off the water, though, so a light jacket isn’t a bad idea if you’re sticking close to the coast.
Visibility and Air Quality
Air quality in Perth during fall usually stays pretty good. As rainfall drops off from early to late fall, dust and pollen in the air go down too. That shift makes it a more comfortable time for anyone with mild respiratory issues.
Most days, visibility turns out excellent, especially when the sky’s clear. You can look across the Swan River or out to Rottnest Island and not deal with much haze.
Sometimes, smoke from prescribed burns drifts in and cuts down visibility here and there. Local crews run these burns as part of land management, mostly during dry spells. Luckily, the smoke doesn’t stick around for long, since wind or rain typically clears things up.