Snow In Western Australia – part one

A special thank you to Graham Barker for generously granting permission to reproduce this article from his webpage: Graham's Paddock.

The images used in this article remain the property of the copyright holder and may not be used without prior written permission.

Mountain Snow

Mountain snowfalls are typically confined to the higher peaks of the Stirling Range in the state’s south. Situated about 90km inland from Albany, this is a range of rugged peaks rising abruptly from low-lying and mostly flat farmland. Five of the peaks rise to over 1000m, with the highest being Bluff Knoll at 1095m. Although not a great height as far as mountains go, in this region it is high enough to receive occasional light snowfalls in most years.

Sometimes, but far less often, snow may also fall on the Porongorup Range. This is a smaller, lower range (highest point 670m) between the Stirling Range and the coast. However, if snow falls on the Porongorups it will have also fallen in greater quantity on the Stirlings, and so Bluff Knoll is the focus for snow-seekers in WA.

Outside of the Stirling and Porongorup Ranges, the only other significant mountains in WA are too far north and of insufficient height to attract snow. Some areas in the southwest which have received rare snowfalls are hilly (eg Perth Hills and around Greenbushes), but these are generally considered as low level falls.

When It Falls

The earliest that snow has been recorded in WA is April 20th (1970), and the latest is November 19th (1992), however it is very improbable towards the ends of this range. Since WA was settled by Europeans (Albany in 1826, Perth in 1829) only three falls have ever been reported in November, and only four falls prior to June.

As the monthly distribution chart shows, the best likelihood of finding snow is in the July to September period. July and August are the coldest months of winter, and although September marks the start of spring, good wintry outbreaks can still occur and the mountain has cooled further. One of the heaviest falls in recent decades occurred in early October, so early spring should not be discounted.

From Bluff Knoll's summit facing east towards Ellen Peak - Image Credit: Graham Barker

When snow does fall, the best accumulation occurs overnight or in the morning when temperatures are lower. Snow showers may occur at any time of day, but even on the coldest days on the highest peaks maximum temperatures are above freezing, even if only just, and melting occurs.

How Often It Falls

Since 1965, reports of snowfalls known to the Bureau of Meteorology (as listed in the historical data page) suggest an average of just over one snow event per year, as shown on the chart below. Prior to this, reports become progressively less complete the further back in time one looks. Low level falls are much less frequent than those on the Stirling / Porongorup peaks, and appear to be decreasing with time. Whether this reflects climate change or not is hard to say, because of the probable incompleteness of the snow records.

Total number of known snow events in WA each year, from 1965 to 2003.
Each horizontal line indicates one day on which snow was reported in WA;
white asterisks (*) indicate snow at low levels as well as on the peaks.

It is not known with certainty how often it snows on the Stirling Ranges. Anecdotal evidence suggests snow may settle on Bluff Knoll two or three times per year on average, with the possibility of a couple more very light falls going unwitnessed or unreported. Instances of snowflakes briefly falling but not settling on the ground - such as in precipitation downdrafts over ground that isn’t cold enough - may occur more often.

Rime formations on Bluff Knoll - Image Credit: Graham Barker

The uncertainty is due to the lack of people in a position to clearly see the snow on the mountains. The Stirling Range sits in a large national park surrounded by thinly populated farmland; apart from the nearby ranger’s residence and caravan park (altitude only 218m, below the snowflakes), there simply aren’t many observers around. Light snow on the summits can be hard to spot from below and at a distance, even if not obscured by cloud, and when clear, a light dusting melts quickly. Falling snowflakes might only be seen by people climbing the summits, but few people do this in the inclement weather required for snow, especially outside of weekends and school holidays.

How Much Falls

Generally less than five centimeters accumulates on the Stirling Range summits, with only the upper portions of the mountains being affected.

Snow on Bluff Knoll summit, looking towards Ellen Peak. One or two light falls settle in most years, but snow of this depth (up to 5cm) is a once in 4 or 5 years event ... and it doesn't usually last the day, so you have to be quick! - Image Credit: Graham Barker

The biggest fall in recent times was in 1992 (October 6) when 20cm was recorded on Bluff Knoll, with snow on the ground all the way down to the car park (altitude approx 450m). Another fall of 20cm was reported in 1998 (July 26), and two falls of 10cm occurred in 1986 (July 15 and August 12). These four occasions were the only falls in the last twenty years to have exceeded 5cm. Prior to that, depth measurements are scarce, but falls described as "heavy" are equally uncommon. On the Stirling Ranges, anything more than a couple of centimeters is cause for celebration.

The Stirling Ranges are very rocky and thickly vegetated, so, other than photography, snowman building and snowball fights are the only snow activities that can be accommodated. Unfortunately skiing, snowboarding or tobogganing are not practical given the terrain and lack of snow depth. An unprecedented low-level snowfall covering the access roads would be needed for this.

How Long It Lasts

Thanks to the marginal conditions and small quantity, West Australian snow doesn’t persist for long. A typical light fall on the Stirling Range summits melts or is washed away within a day of it falling. The longest lasting known snowfall in WA occurred in 1923 when snow remained on the Stirlings for four days, and heavy falls in 1992 and 1998 lasted about two days, but these were rare exceptions. Even during WA’s most widespread snow event in 1956 (June 26), the Stirlings’ snow had all melted by the following morning.

Near Bluff Knoll's summit facing south - Image Credit: Graham Barker

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Low Level Snow

Occasionally snow falls and perhaps briefly settles on the ground at low levels (from 100m to 350m altitude) in inland south-western Australia. Snow in the goldfields region (around 400m altitude) further to the northeast has also occurred but is more rare. Snow near the coast or near sea level is extremely rare.

A recent example occurred on August 22nd 2003 when 3cm of snow fell in Ongerup, 60km north of the Stirlings and only 286m above sea level. It also fell on surrounding areas including the towns of Gnowangerup and Jerramungup, but nowhere else in WA apart from the Stirling Range. Details of this event can be found at the Australian Weather News website.

The exceptional winter and spring of 1992 also brought snow (in four separate events) to Borden, Broomhill, Katanning, Wagin, Cranbrook, Mt Barker, Kojonup, Arthur River, Rocky Gully, Manjimup, Greenbushes, Boyup Brook and Darkan. Notably, the last of these snow events occurred in November, less than a fortnight before the official start of summer.

The most widespread snowfalls yet experienced in WA occurred one morning in 1956. Snow was observed in some Perth Hills suburbs, as far north as Wongan Hills, as far east as Salmon Gums, and a large number of other locations throughout the south west. Details of these and other WA snowfalls can be found in the historical data section.

The map below shows locations in Western Australia where snow has been reported (click on it to see a larger version, 337kb). Locations are marked by red squares, their size varying according to the number of times snow has been reported there (either 1, 2-3, 4-5 or 6+ times). Reported snowfalls vary from snowflakes melting upon touching the ground, through to snow settling and covering the ground - the map does not distinguish between type of snowfall (see the Historical Data pages for more details). Also be aware that snow has almost certainly fallen in places and at times not captured in the historical records.

In other words, use this map only as a general indication of where snow has occurred, not a definitive record.

Map showing distribution of low-level snowfalls in Western Australia

Low level snowfalls in WA share the following characteristics:

  • They are light, rarely reaching more than a few centimetres in depth. Many reports refer to snowflakes falling but melting upon touching the ground.
  • They are short-lived - even if snow settles on the ground it melts soon after, most commonly within half an hour.
  • They are very rare - in most years, low-level snowfalls do not occur at all. Any given area that receives one may not receive another for decades, or longer. For example, the 2003 Ongerup fall was the first significant low level snow in WA since 1992, and the first in Ongerup for 50 years.
  • They are often localised to small areas - it may snow in one town but not its neighbour. The 2003 Ongerup snowfall affected only that area, and not higher places further away.
  • They are virtually impossible to predict. Even in the unlikely event of favourable conditions, the localised nature of low level snowfalls makes it hard to guess which areas may get some and which will miss out.

Experiencing low-level WA snow isn’t something that can be planned or expected, so for anyone seeking snow in WA the only place where there is a realistic chance of finding any in a normal year is on the Stirling Ranges.

How Much Falls

The heaviest falls reported to have settled at low levels occurred on the morning of June 26, 1956. Up to 15-20cm covered paddocks near Borden, north of the Stirling Range. Some other Great Southern and Southwest district locations from Toolbrunup to Boyup Brook accumulated up to 7.5cm. Gnowangerup received 6.3cm, while 5cm was reported near Collie and Kojonup. None of these snow depths persisted very long.

Outside of that exceptional 1956 snow event, the most significant depth was 7.5cm at Greenbushes in 1900. Otherwise, falls are generally less than 2.5cm; any snow that settles and briefly covers the ground is a rare event.

How Long It Lasts

At low levels, the most durable snowfall occurred in the town of Greenbushes in 1900 when snow covered the ground for four hours. However, at low levels, snow rarely lasts more than half an hour before melting. This is due to temperatures at ground level seldom being low enough to sustain snow for long; even on the coldest of cold days, maximum temperatures rarely fail to reach 8°C in inland towns. Also, snowfalls are inevitably followed by rain, which quickly washes away what little cover there may have been. Many reports of snowfalls involve snow falling but melting upon contact with the ground.

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