Welcome to the Climate and Water Outlook for May–July 2018. Warmer than average conditions in April look set to continue in May, while drier than average conditions are possible in parts of southwest Western Australia and western Victoria. But first, let's look at recent conditions. 
In the tropics, the wet season is ending—having delivered average to above-average rainfall since October. 
[Rainfall deciles map for 1 October 2017 – 23 April 2018 shows above-average rainfall totals for the wet season in the north of Western Australia, the Top End of the Northern Territory, and some northern parts of Queensland.]
This included nine tropical cyclones in the Australian region—close to average for a season. Tropical lows also brought flooding to Broome in January and to western Queensland in March, easing drought conditions. 
Water is now flowing inland through Queensland's Channel Country, past Birdsville, and is headed towards Lake Eyre. 
[Satellite footage of area around Birdsville, 10 March – 17 April 2018, shows increased river flows moving south across the Queensland – South Australia border.]
In contrast, large areas of southern Australia have had little rain since January. 
[Rainfall decile map for 1 February – 23 April 2018 shows well below average rainfall totals for the three-month period down the southwestern coast of Western Australia and over much of South Australia, most of New South Wales and all of Victoria. Above-average rainfall totals have been see in the northern Kimberley in Western Australia, in northern parts of Queensland, and in southeastern parts of Western Australia.]
Autumn in the south felt more like summer: Temperatures in the first two months of the season were unusually high. Bushfire activity continued in Victoria, New South Wales and South Australia, and dry topsoil was lifted into dust storms.
The prolonged heatwave in early April was exceptional. New April temperature records were set in many parts of the country, over several days.
[Maximum temperature anomaly maps for 1–9 April 2018 show maxima more than 8°C above average for the time of year in parts of every State and Territory on the mainland, increasing to more than 12°C above average in southeastern WA, South Australia, western New South Wales and western Victoria by 8–9 April.]
Australia as a whole had its hottest April day on record on the 9th, with a national average close to 35°C. 
[Graphic shows average Australian maximum temperature on 9 April 2018 was 34.97°C.]
With little rain and high temperatures leading to high evaporation, soils have remained very dry in the south.
[Lower-layer soil moisture map for 1–22 April 2018 shows moisture levels very much below average for the time of year in most of the west of Western Australia, most of South Australia and New South Wales, and in northern and far eastern parts of Victoria. Soils are wetter than average, though, for most of Queensland and Tasmania.]
Water storages in the southeastern mainland are lower than at this time last year. In Tasmania and the southwest of Western Australia, storages are higher than last April.
[Water storage graphics for April 2018 show storage levels in the Murray–Darling Basin at 51 per cent full (down from 67 per cent in April 2017), levels in the NSW part of the South East Coast drainage division at 73 per cent (down from 93 per cent in April 2017), the Victorian part of the South East Coast at 40 per cent (down from 49 per cent in April 2017), the South West Coast of Western Australia at 37 per cent (up from 30 per cent in April 2017), and Tasmanian storages at 57 per cent full (up from 52 per cent in April 2017).]
In areas with dry soils, any rain will first soak into the ground before it begins to flow through catchments. This means that once the rains do arrive, the winter water storage filling season is likely to start late in the south.
So what's driving our climate right now? Both the Pacific and Indian oceans are showing neutral climate patterns, and are likely to stay that way into winter.
However, warm sea surface temperatures around New Zealand and low air pressures over the Tasman Sea are forecast to continue. This may weaken the westerly winds that bring moisture into southern Australia. 
[Sea surface temperature maps for 13–19 April 2018 show waters close to average temperature for the time of year across the Pacific Ocean and Indian Ocean, but areas 2–4°C warmer than average around the South Island of New Zealand and in the northern Tasman Sea.]
So what's our rainfall outlook for May–July? The rainfall outlook shows little shift towards a wetter or drier than average season for much of the country. But below-average rainfall is likely for parts of southwest Western Australia and western Victoria. The north is also likely to be wetter than average, but it's the start of the dry season, so it won't be as wet as recent months.
[Rainfall outlook map for May–July 2018 shows 30–40 per cent chances of above-average rainfall totals for the three months in the south-west of Western Australia and some western parts of Victoria, and 70–80 per cent chances of above-average rainfall for the time of year (NB it's the dry season) in the Top End of the Northern Territory.]
The streamflow forecast for April–June is for mostly low and near-median flows, particularly in the south. High flows are more likely in Queensland, following that heavy rainfall we saw in March. 
[Streamflow forecast map for April–June 2018 shows lower-than-average flows for the time of year are most likely at 42 locations, particularly in the south of the mainland. Near-median streamflows are most likely at 33 locations, spread around Australia. Higher-than-average flows are expected at 28 locations, mostly in Queensland.]
In terms of temperatures: In May, warmer-than-average autumn temperatures are likely to continue. 
[Maximum temperature outlook map for May 2018 shows greater than 70 per cent chances of above-average daytime temperatures for the month across the majority of the country—rising to more than 80 per cent chances for the north of Western Australia, most of the Northern Territory, southern Queensland and most of New South Wales.]
But as we move into winter, there's less chance of warmer than average temperatures in all but some southern parts of the country.
[Maximum temperature outlook map for May–July 2018 shows neutral outlooks (close to 50 per cent chance of above- or below-average temperatures over the three-month period) for most of the mainland, rising to 70–80 per cent chances of above-average daytime temperatures in southern and eastern Victoria, and more than 80 per cent chance for most of Tasmania.]
So in summary: there is little shift towards a wetter or drier season for much of the country, but it's likely to be drier than average in parts of southwest Western Australia and western Victoria; temperatures are likely to be warmer than average in May; but closer to average for winter for most parts; and low or near-median streamflows are likely at most locations, with high streamflows in Queensland.
For more details, visit our website at bom.gov.au/climate/ahead. You can also get updates via Facebook and Twitter.
Our first look at likely conditions for winter will be available on Thursday 17 May.
For the Bureau of Meteorology, I’m Felicity Gamble.