Annual climate statement 2015

February was a very warm month for Australia, although the overall story was one of persistent warmth and an absence of cold days rather than extremely warm days. Nevertheless, daily maximum temperature records were set at several sites in Western Australia including 49.2 °C on the 21st at Roebourne Aero, 47.6 °C at Eucla and 47.5 °C at Forrest on the 14th, and 39.6 °C at Kalumburu on the 18th. Roebourne Aero's 49.2 °C on the 21st was the highest maximum temperature in Australia during 2015, while the overnight minima at Wittenoom for the 21st (35.1 °C) was the highest minimum temperature for Australia during 2015.

There were three consecutive days between 8 and 10 February when the Australian area-averaged maximum temperature exceeded 38 °C; this is only the second time this has occurred, with the previous run of days during 14 to 16 February 1983 (which remains Australia's warmest February on record).

An exceptional autumn hot spell affected large parts of northern and central Australia during March. At the start of the month a warm spell occurred over the Top End, Gulf Country, and northwestern Queensland. From mid-month, unusual heat was recorded over a much larger area, with records set in large parts of the Northern Territory, Queensland, outback South Australia and northern New South Wales at the peak of the event on the 19th and 20th. Records were also set for area-averaged temperatures, runs of warm days, and late-season heat (see Special Climate Statement 51: An intense heatwave in central and eastern Australia). The exceptionally warm March was substantially enabled by the early conclusion of the 2014–15 northern Australian monsoon—at this time of year temperatures are typically moderated by cloud cover, damp soils, and green vegetation.

A very warm spell affected northern Australia during the latter part of July, as a strengthening high pressure system moved over southern Australia. The system extended a dry air mass into southern and western Queensland in the wake of a surface trough, with dry inland air pushed through central parts of the Northern Territory and the Kimberley district on the following day, spreading to more inland parts of Western Australia by the 29th. Several locations in central and western Queensland, around the Top End and the northwest of Western Australia experienced their warmest July day or night on record between the 26th and 30th.

A warm spell emerged in early September as a large high pressure system tracked slowly eastward across the Bight, combining with a trough near the west coast of Australia, and directing warm northerly winds over western parts of Western Australia from the 7th to 9th. The unseasonable warmth, with maxima more than ten degrees above average, contracted to the central and southeastern parts of the state on the 10th as the high moved eastward and a cold front crossed the west coast. Some early season records were observed during the event, including Perth's maximum of 32.1 °C on the 9th, which was its earliest occurrence of 32 °C in September in 117 years of record. Daily maxima more than six degrees above average were also observed across most of Victoria between the 12th and 14th as the front progressed eastward.

Following a very dry September, heatwave conditions developed over parts of the South West Land Division in Western Australia from 1 October, before extending into the mainland southeast (see Special Climate Statement 52: Australia's warmest October on record). Temperatures peaked between the 4th and 6th, with early-season heat records set across large parts of southern Australia. Further extreme high temperatures were observed in the south of Western Australia between the 8th and 13th, and again on the 22nd. While the remainder of the month was not as exceptional as the first half, temperatures generally remained well above average and contributed to the month becoming Australia's warmest October on record. Furthermore, October 2015 had the largest mean temperature anomaly on record for any month.

For the southeastern mainland, area-averaged October maximum temperatures were close to temperatures typical of December, with monthly anomalies in excess of five degrees observed for Victoria, New South Wales, and South Australia. New South Wales, Victoria, South Australia and Western Australia all observed their warmest on record for both maximum and mean temperatures, while the remaining regions were in the top nine warmest on record for October.

Significant agricultural losses resulted from the dry and warm conditions during September and October as large areas of crops across southern Australia failed and were cut for hay. Estimated losses were expected to be on the order of at least $1 to $2 billion in Victoria alone.

Extreme heat affected much of southeastern Australia in the third week of December following a consistently warm first half of the month (see Special Climate Statement 53: widespread record December temperatures in southeast Australia). From the 13th an extended period of hot weather became established over South Australia, intensifying on the 16th as high pressure became established in the Tasman Sea and directed hot northeasterly winds over South Australia. Heat peaked on the 19th in South Australia and Western Victoria before a cool change passed through the southeast on the 20th, bringing relief.

Numerous December records were broken in South Australia, Victoria and Tasmania for daily maximum temperature. Exceptionally high minimum temperatures on the night of 19–20 December were even more significant, with record-high minimum temperatures for December observed over large parts of Victoria and Tasmania and some parts of eastern South Australia and southern New South Wales.

Particularly hot and windy conditions developed over the south and west of South Australia ahead of a trough during the first few days of January. On the 2nd, severe fire danger was observed in fourteen out of the fifteen districts, and was extreme or catastrophic in eight. On the following day twelve districts observed at least severe fire danger. Several fires started during the 2nd, including a large fire at Sampson Flat in the Mount Lofty Ranges. The Sampson Flat fire burned 20 000 hectares between the 2nd and 9th, with widespread rain on the 9th and 10th helping bring the fire to a conclusion. The fire destroyed 27 houses and numerous other structures.

As the trough tracked eastward significant fire weather was also observed across Victoria. Bushfires started on 3 January in the Little Desert National Park and Black Range State Park in western Victoria, and had burnt around 4000 hectares by the 5th. A fire at Moyston, west of Ararat, destroyed two homes, damaged around 90 other properties, and burnt 5000 hectares before being brought under control by the 4th.

Significant fires occurred in South West Western Australia in late January and early February following widespread thunderstorms on the afternoon of 28 January in which lightning ignited numerous fires. The two most significant were the Boddington fire, which burnt approximately 52 000 hectares of forest and farmland over seven days, and the Northcliffe fire.

The Northcliffe fire escalated rapidly on 4 February when a strong high pressure system over the Great Australian Bight directed very warm northerlies over the region. The fire burned close to 100 000 hectares, including approximately 4500 hectares of private land and two homes. The fire was one of the most significant on record for this region and the largest individual fire in the south-west forests since the Dwellingup fire of January 1961.

The South West Highway between Middleton Road and Northcliffe was closed for a period of three weeks, while both the Boddington and Northcliffe fires destroyed sections of the historic Bibbulmun Track, including the 66-year-old Long Gully timber trestle bridge over the Murray River.

Periods of significant fire weather continued throughout February in southern Australia, although there were no further significant fires.

Below average winter–spring rainfall and a very warm start to October created conditions conducive to dangerous spring fire weather across the southeast. Extreme fire danger was declared over much of Victoria and parts of Tasmania during the early October heatwave; Forest Fire Danger Index (FFDI) values at a number of sites were near record-high for so early in the season.

During early October, more than 70 fires burnt in hot and windy conditions in Victoria, with around another 55 in Tasmania.

The most significant fire during October was that at Lancefield, north-northwest of Melbourne. It had been started as a control burn during the preceding week, escaped control lines on the 3rd, and spread on the 6th as a result of the hot, windy conditions. The fire burnt 4000 hectares and destroyed four houses and about two dozen sheds before it was contained on the 11th. Other fires occurred on the 5th near Tallarook, north of Melbourne; at Wensleydale near Geelong; near Port Lincoln in South Australia; on the northern outskirts of Hobart; and later in the month south of Geeveston in Tasmania, when a number of new fires and re-ignitions were reported in a burst of hot and windy weather on the 15th.

Periods of very severe fire weather also occurred during November. Lighting contributed to the ignition of a number of fires around Esperance in Western Australia on 15 November. These fires continued to burn and became uncontained on the 17th in catastrophic fire weather with very hot, dry and windy conditions followed by a significant wind change. Four people perished in the fires, which collectively burnt 145 000 hectares, including vast areas of cropping land.

Large bushfires burnt in South Australia in late November as hot and very dry conditions with strong north to northwest winds ahead of a strong change led to catastrophic fire danger ratings in the Mid North and Murraylands districts on the 25th. The most significant was the Pinery fire north of Adelaide, which travelled more than 50 km in the first four hours, initially running southeastwards along a narrow front, but spreading from the long eastern flank when the wind turned. About 90 000 hectares of mainly agricultural land was burnt before containment on the 27th, most by the end of the first day. Tragically, two people perished and several more were seriously burned. At least 87 houses were destroyed or severely damaged, along with numerous other structures, and thousands of livestock animals (including at a piggery and chicken farm engulfed by the fire).

Fires also occurred in Victoria and New South Wales, although without significant damages.

Extensive property losses occurred in Victoria in late December. A bushfire west of Lorne, believed to have been ignited by a lightning strike on 19 December, flared up in hot, windy conditions on the 25th, destroying 98 homes and holiday houses at Wye River and a further 18 at Separation Creek. Fortunately no lives were lost. The fire was relatively small for the high toll in property, burning somewhat less than 3000 hectares of steep, difficult and heavily-treed terrain by the end of the year. The fire was expected to continue to burn for a number of weeks.

There were nine tropical cyclones in the Australian region during the 2014–15 season, slightly below the 1969–2014 average of 11. Of these, seven occurred during 2015: Lam, Marcia, Olwyn, Nathan, Ikola, Quang, and Raquel.

Severe tropical cyclone Marcia was the most intense cyclone to make landfall during 2015, and the most intense landfall known so far south on the east coast. Marcia underwent a period of rapid intensification, going from topical low to category 5 strength during the two days prior to making landfall around 8 am on the 20th at Shoalwater Bay, north-northwest of Yeppoon. Marcia caused extensive damage in Yeppoon, Byfield, Rockhampton and Biloela, before weakening steadily as it tracked southward. Heavy rain and some areas of flooding were reported along the east coast as far south as Lismore in New South Wales. The State Emergency Service (SES) received almost 3000 requests for assistance, mostly from central Queensland. Reported damages totalled at least $750 million.

Severe tropical cyclone Lam also made landfall on 20 February, the first time in recorded history that two severe tropical cyclones made landfall in Australia on the same day. Lam formed early on the 17th in the Gulf of Carpentaria and crossed the Top End coast early on the 20th as a category 4 storm, but weakened rapidly over land and was below cyclone strength later that afternoon. Lam caused heavy rainfall in parts of the Top End and the Cape York Peninsula and extensive structural damage and disruptions to power supply and communications on Elcho Island and at Milingimbi and Ramingining.

Severe tropical cyclone Nathan was a very long-lived system, reaching category 2 strength over the Coral Sea on 11 March and lingering to the east of the Cape York Peninsula before making landfall to the north of Cooktown as a category 4 storm early on the 20th. Subsequent landfalls occurred on the Arnhem coastline south of Nhulunbuy at category 2 strength on the morning of the 22nd, crossed Elcho Island, and made landfall west of Maningrida in the Top End at category 1 strength early on the 24th. Nathan brought heavy rain to parts of Far North Queensland around mid-March and again later in the month over northeastern Queensland and the north of the Northern Territory, although causing little further damage to areas affected by Lam a month earlier.

Severe tropical cyclone Olwyn reached category 3 strength as it approached the Pilbara coast on 12 March. Olwyn passed west of Exmouth during the 13th and tracked southwards along and over the coast before moving over land south of Carnarvon. Olwyn weakened to tropical low strength near Geraldton on the 14th after bringing heavy rain and damaging winds over coastal areas. Areas of rain extended further inland and southwards over following days. Minor flooding resulted in the Gascoyne, Greenough and Irwin catchments with several towns and communities declared natural disaster zones. Extensive power outages and damage to banana plantations were reported, as were some road closures.

Severe tropical cyclone Quang produced widespread moderate rainfall in the Pilbara and adjacent areas of Western Australia at the start of May, having formed during the last days of April. Quang had reached category 4 strength while well offshore, but was likely below cyclone strength when it made landfall between Exmouth and Onslow just after 6 pm on 1 May, although damage was reported at Exmouth in the hours before the cyclone reached the coast.

Tropical cyclone Raquel remained well to the northeast of Australia over the Solomon Islands, but was unusual because it occurred at the end of June. A cyclone had never been recorded in the eastern Australian region this late in the season during the satellite era; the only previous winter cyclone recorded in the region was Ida, which occurred in early June 1972.

Tropical cyclone Ikola, which occurred during April 2015, remained well off shore and did not cause damage to any land masses while a cyclone, although the remnants of Ikola caused moderate to heavy rainfall in the southern third of Western Australia between 9 and 14 April.

Significant rain over Central Australia and parts of South Australia and western Queensland during the first half of January was associated with the passage of a tropical low. Large parts of Central Australia received 300% to 400% of its average monthly rainfall for January, or about as much as the average annual total, between the 4th and 11th, with some areas experiencing flooding. In the Alice Springs district it was a one in 10- to 15-year event, with numerous stations picking up weekly totals in the 200 mm to 250 mm range. Major flood warnings were issued for the Georgina River and Eyre Creek in western Queensland between the 20th and the end of the month. Kati-Thanda Lake Eyre also experienced significant inflow, which was somewhat unusual as it mostly resulted from local rainfall; Kati-Thanda Lake Eyre more typically receives water flowing from rainfall over inland and western Queensland.

A slow-moving East Coast Low developed off the Hunter coast on the evening of 20 April, producing severe weather across much of coastal New South Wales before decaying during the 23rd. Two-day totals as high as 436 mm were recorded at Tocal and Maitland, and hourly totals as high as 112 mm in Tocal on the morning of the 21st.

Twelve regions were declared natural disaster areas following extensive damage associated with heavy rain, prolonged high winds, and flooding. Major flooding was observed in the Williams and Patersons rivers, with flash flooding reported throughout the Sydney, Hunter, and Central Coast regions. Almost 80 homes were badly damaged in Dungog, with several fatalities, in severe flash flooding on the morning of the 21st. Strong winds and high seas also contributed to substantial coastal erosion, with sand blown well beyond the immediate beachfront. In total, the SES reported more than 20 000 callouts and 169 flood rescues during this event, the largest response operation in the history of the service. It was the most severe East Coast Low to affect the New South Wales coast since at least June 2007.

Another East Coast Low, which developed in a coastal surface trough during 1 and 2 May, brought widespread moderate to heavy rainfall, powerful surf, and damaging winds to southeast Queensland and parts of northern and coastal New South Wales. Localised flash flooding resulted around Brisbane and the Gold Coast, with flood warnings also issued for multiple catchments in southeast Queensland and northeast New South Wales. Heavy rain continued in coastal New South Wales until the 4th as the low tracked southward. Four lives were lost north of Brisbane when two vehicles were swept from flooded roadways. A number of flood rescues were also conducted in New South Wales, and one fatality was associated with dangerous surf.

A southerly dip in an offshore trough at the start of June brought showers and storms to parts of the eastern Top End and Cape York Peninsula in Queensland, with some locations in the Northern Territory and Queensland observing their wettest June day on record on the 1st. A few locations in southern Queensland also observed their wettest June day on record on the 16th or 17th when a broad, slow-moving surface trough brought moderate falls to large parts of eastern Australia. Several days later, a cut-off low brought heavy showers to the coastal South West District of Western Australia on the 19th, resulting in flash flooding in Yallingup west of Busselton.

A low pressure system crossed New South Wales in late August during the 23rd and 24th, triggering thunderstorms in northern and eastern New South Wales and parts of the Darling Downs and Granite Belt in Queensland. A tornado at Dubbo caused moderate to extensive damage to at least 12 properties in Dubbo on the afternoon of the 24th, while flash flooding occurred in the Sydney CBD. The low developed into an East Coast Low on the evening of the 24th. The system produced high winds and 48-hour totals in excess of 300 mm to 9 am on the 26th for parts of the Illawarra and South Coast districts of New South Wales, including some daily records for August rainfall. Heavy rain continued in Victoria on the backside of the low, with some parts of the State receiving record-high August daily rainfall for the 24 hours to 9 am on the 28th.

Substantial flooding occurred in the Illawarra and South Coast areas, moderate flooding in the Shoalhaven River, and major flooding in St Georges Basin. Warragamba Dam started spilling on the morning of the 27th, for the first time since June 2013, causing minor flooding in the Hawkesbury–Nepean River. Particularly high dam levels at Jerrara Dam resulted in evacuation orders due to possible dam failure, although dam failure did not eventuate, with evacuations also ordered in parts of Sussex Inlet and St Georges Basin. The New South Wales SES received more than 1800 callouts during the event and preceding thunderstorms, with 95 flood rescues.

An active monsoon trough extended across the Top End and through the Gulf of Carpentaria in the last week of December. Significant rainfall totals were observed over areas of the western Top End between 24 and 27 December, with many locations recording cumulative totals of 400 mm to 500 mm, with isolated areas receiving over 600 mm. The low progressed eastward then tracked slowly southwards from the Gulf of Carpentaria during the last days of December, bringing significant rainfall over the east of the Northern Territory and adjacent areas. Some locations in the north and northeast of the Northern Territory and northern Queensland received record December daily rainfall in the last week of the month.

The Naiuyu (Daly River) community was evacuated, with the Daly River reaching Major Flood Level (15.0 m) and flood watches issued for other areas along the Northern Territory's eastern border. A number of major roads across the Northern Territory and Central Australia were cut by flooding. Kati-Thanda Lake Eyre experienced significant inflows from the event, in large part due to locally heavy rainfall in the immediate vicinity, which continued into the first days of 2016.

Frequent strong winds occurred in Tasmania during January. Strong winds and heavy rain occurred on the State's east coast between the 13th and 14th, associated with the southward passage of a low. Areas of flash flooding, 27 calls to the SES for assistance, and damage to cherries and stonefruit, especially in the Huon Valley, were reported. Strong winds and localised reports of damage associated with cold fronts also occurred around mid-month. On the west coast, cold and windy conditions damaged leatherwood flowers, reduced nectar flow, and discouraged bees from working, greatly reducing the production of leatherwood honey.

On 7 January, severe thunderstorms occurred over Melbourne with gusts up to 100 km/h, widespread power outages, wind damage and fallen branches, and over 1000 SES callouts. There were also extensive thunderstorms over southern South Australia, with a roof lifted at Karoonda.

On the 8th, a tropical disturbance developed over the far north of South Australia, slowly moving southward and deepening before moving into Bass Strait on the 13th. Bands of rain and thunderstorms from this system affected the north and east of South Australia, the western half of Victoria, and parts of New South Wales. There was flash flooding reported in South Australia and Bendigo (where 100 mm of rain fell in one hour), along with 156 SES callouts across Victoria.

Thunderstorms causing flash flooding were also reported on the 19th in the Wide Bay and Burnett district of Queensland and along the central coast of New South Wales, where heavy rain combined with very high tides.

Heavy rain across much of the central and northern coast of New South Wales on the 26th and 27th caused flash flooding in Sydney and burst the banks of the Parramatta River, with widespread flash flooding in the Port Macquarie region as well as a flood rescue near Coffs Harbour. Further heavy rain and flash flooding occurred around Coffs Harbour on 1 and 2 February.

Storms continued in February, with the most damaging including:

• heavy rain and thunderstorms in Melbourne on the 22nd and 23rd and severe storms in Shepparton on the 23rd, resulting in fallen trees and minor damage, with 50 SES callouts
• thunderstorms and strong winds in central New South Wales on the 25th, with flash flooding, minor roof damage, flood rescue of trapped cattle, and minor to moderate flooding along the Wilsons, Brunswick and Tweed rivers
• thunderstorms along a surface trough in the Great Southern and Goldfields districts of Western Australia on the 26th, with minor damage reported in Kalgoorlie and Kambalda
• severe storms in Melbourne and the eastern suburbs on the evening of the 28th, with wind gusts to 130 km/h, causing extensive power outages, felled trees, structural damage. There was one fatality and one seriously injured when a tree fell onto a Dandenong Ranges home. The SES received around 1700 callouts.

Strong and gusty winds affected much of Tasmania on 5 and 6 March as a cold front crossed the State. Damage to trees, roofs and power lines was reported in the northwest and around Hobart, while wind also made a bushfire in State forest near Lefroy in northern Tasmania difficult to control.

Thunderstorms were common in New South Wales during March, with significant storms reported:

• in Sydney on the 1st, with 500 calls for assistance to the SES for roof damage and downed trees and powerlines
• around the Grafton region on the 9th, resulting in numerous downed trees and leaking roofs following rain rates of up to 50 mm in 30 minutes
• in Sydney and the Illawarra on the 11th, causing widespread power outages, lifting the roof of a house onto the train tracks at Mt Druitt in western Sydney, with about 150 SES callouts and lightning strikes implicated in several house fires
• on the central coast and Blue Mountains on the 12th, with some reports suggesting hail of up to 10 cm in diameter in Faulconbridge
• in the Narrabri region on the 21st, with hail of more than 7 cm in diameter causing widespread damage to crops, roofs, cars and windows
• at Dulwich Hill in inner western Sydney on the 31st, causing locally heavy rain and strong winds, some damage to roofs and trees, and localised flash flooding

Strong winds affected the southeast between 5 and 14 May owing to a vigorous westerly airstream with embedded lows and cold fronts. The winds raised the sea level in and around Port Phillip in Victoria by about half a metre, with minor coastal inundation resulting. There was also minor wind damage reported about parts of the Yorke Peninsula and the southern Mount Lofty Ranges in South Australia on the afternoon of 4 May and into the 5th, with the SES responding to 240 callouts. A dust storm crossed western Victoria and southwestern New South Wales on the 5th, reaching Sydney and the Illawarra by the 6th on south to southwesterly winds behind one of the fronts. In Tasmania, wind and locally heavy rain on the 5th and 6th caused widespread power outages, reports of roads blocked by fallen trees and some damage to structures. The SES received 45 callouts from the northwest of Tasmania. Later in the week several sites recorded their strongest May wind gust on record on the 12th.

A strong cold front crossed Tasmania late on 7 June, with a few sites observing their strongest June gust on record on the 8th. Many sites recorded gusts in excess of 100 km/h: Maatsuyker Island's 185 km/h gust was a new Australian record for June. Power outages resulted at up to 15 000 premises and some trees were felled although relatively little property damage was reported.

Strong winds associated with the passage of a cold front on 10 July damaged at least 12 buildings at Burrumbuttock in the New South Wales Riverina region, as well as removing the roof from a home in Armidale.

Slow-moving thunderstorms developed over Adelaide on the afternoon of 16 September associated with an area of low pressure, with large accumulations of small hail and heavy rainfall in the eastern suburbs. The SES received around 190 callouts. On the 17th, the depression merged with a surface trough lying inland of the Great Dividing Range through Queensland and northeastern New South Wales, producing storms in parts of the Hunter Valley and Central Coast districts of New South Wales. There were reports of heavy falls of small hail, hailstones up to golf-ball size, localised flash flooding, power outages and traffic disruptions, as well as downed trees and leaking roofs. The New South Wales SES received close to 500 calls for assistance, mostly northeast of Gosford.

A strong wind change which passed through the southeast during the afternoon of 6 October caused challenging conditions for firefighters battling a number of bushfires in several States. It also resulted in widespread wind damage to trees and some structures in Victoria, with 315 SES callouts.

Areas of very heavy rain and thunderstorms occurred across many areas of Australia during October, including:

• intense but patchy storms across Victoria during the 11th and 12th causing heavy rain, fallen trees, and power outages across the city and eastern suburbs, as well as ending Melbourne's run of 19 dry days; a run which equalled the record for September and October
• thunderstorms in parts of the South West Land Division and Goldfields district in Western Australia overnight on the 17th to 18th and on the 25th, with hail causing extensive crop losses in some areas
• severe thunderstorms and large hail in inland southeastern Queensland and around the northeast of Brisbane between the 27th and 29th, with widespread structural damage at Fernvale and Chinchilla

Gale-force and gusty winds in southern Tasmania on 17 October caused damage to structures and trees, while on the 26th wind damaged the roofs of three buildings in the Tamar Valley.

Thunderstorms were again numerous over eastern Australia during November, with notable storms including:

• on the 1st across northern Victoria and southern New South Wales, causing mostly minor damage, but with a tornado west of Cobram at Strathmerton removing roofs from several houses
• heavy rain on the 5th leading to flash flooding in northwest Victoria and around Melbourne, with funnel clouds also spotted over the northern metropolitan area
• heavy rain and hail in Sydney and the central coast on the 13th, with 160 SES callouts, power outages, and some localised flash flooding
• several occurrences of hail of 4 cm to 6 cm diameter in eastern Queensland from mid- to late November

A cold front crossed Victoria on 25 November causing widespread strong winds with gusts exceeding 100 km/h, felling trees in northeastern Victoria and northern and eastern suburbs of Melbourne with widespread, but mostly minor, damage reported.

A series of severe thunderstorms crossed the Sydney region on 16 December. A category F2 tornado damaged several properties and the desalination plant in Kurnell, with a wind gust of 213 km/h recorded, the strongest wind gust ever recorded in New South Wales. The thunderstorms also produced heavy rain and localised flash flooding, with 53 mm in 30 minutes in Rose Bay. The heavy rain collapsed a roof in Bondi Junction Westfield, while hail larger than 3 cm in diameter was reported in several locations in southeast Sydney including Cronulla.

Snow fell to low levels in Tasmania several times during May. A cold front that crossed on the 6th brought snow to highland areas and, by the morning of the 7th, snow had settled below 200 metres in the south. Heavy falls in some elevated regions led to road closures. The passage of another cold front on the 12th saw snow to below 300 metres on the morning of the 13th.

Snow to low levels also occurred in Tasmania during early June, falling to below to 300 metres on the 1st, and below 500 metres on the 9th, and in July to below 400 metres on the 2nd, and down to around 500 metres on the 27th. Again, each instance led to some roads being closed.

Despite a promising start to the snow season in the Australian Alps, with around 13 cm of snow recorded at Spencers Creek early in June, the lack of snow by the end of June was more notable. 2015 joins three previous years (1967, 1979 and 1991) in which there was no snow on the gound at Spencers Creek at the last June observation time and snow at the first July observation. Snow depths at Spencer's Creek increased from just 4. cm on the 9th—the latest date on record to have less than 5 cm of snow—to 122.4 cm at the start of August—close to the 1961–1990 average. Overall, the season commenced late and was brought to an early end by a mild and dry spring. The maximum snow depth was also well below average at 148.8 cm (average is 195.7 cm).

Between 11 and 17 July a significant cold outbreak occurred when a sequence of strong cold fronts crossed eastern Australia. The cold fronts were associated with low pressure centres which exhibited East Coast Low behaviour upon reaching the eastern seaboard; this aided the strength and reach of cold southerlies. The event was notable for its spatial extent, with widespread snow along the Great Dividing Range from the Southern Tablelands in New South Wales to the Granite Belt in southern Queensland. Light falls were also recorded in the ranges east of Melbourne early in the sequence, becoming more widespread in elevated parts of the State on the 14th–15th; however, these snowfalls were not particularly unusual. Settling snow was reported to levels as low as 400 metres across the central west of New South Wales, which is more uncommon. For locations in elevated areas of southeast Queensland it was the heaviest snowfall since 1984. The snow and ice on roads caused disruptions and road closures in multiple areas, while high winds associated with the cold fronts also caused some damage and disruption to power supplies.

Snow fell to near sea level several times in the first week of August as strong cold fronts crossed Tasmania. Some roads and schools were closed in western and central areas of Tasmania on the 1st and 2nd. More widespread falls on the 3rd, including Hobart's most significant snow event since July 1986, led to extensive road and school closures and power outages in northern, central and southern areas. 28 crashes were reported, mostly in northern Tasmania, in the wet, snowy, icy conditions. On the 5th snow again fell down to 100 metres in south and west, with associated road closures.