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The graphics and statistical information on this page fill gradually as they become available, with some not available until the next day.
The page is updated every 30 minutes at about 20 and 50 minutes past the hour.
For weather news as it breaks that is tagged and organised, use the links on the Weather and Climate Media Reports page.
 Chance of El Niño eases - but ever so slightly
The array of climate models the Bureau of Meteorology uses to forecast long-term climatic changes have reduced the likelihood of an El Niño developing this year compared with last month's.
However, in its latest ENSO Wrap-Up, issued today, the Bureau says "five of eight international climate models still indicate the tropical Pacific Ocean may exceed El Niño thresholds during the second half of 2017" but adds that the models have lower forecasting accuracy during autumn. BoM also notes that sea surface temperatures in the tropical Pacific have warmed since the start of 2017, though they, and some other indicators, remain below El Niño levels. The BoM is maintaining a watch status for El Niño, meaning that they consider there is still a 50% chance of it developing in coming months.
Forecasts for the Indian Ocean Dipole (IOD) also remain neutral, with four of six climate models expecting a positive IOD to develop during winter. An El Niño often brings a dry winter/spring to eastern Australia and, if coupled with a positive IOD, extends the dry area farther west.
The 9 May ENSO Wrap-Up is here, and includes links to a video and poster that explain how El Niño works.
 Tropical Cyclone Donna menaces New Caledonia
Tropical Cyclone Donna is threatening New Caledonia, and at 19.00EST this evening lay 220km NNE of the capital, Nouméa. It has been downgraded from the Category 5 level it maintained for about 24 hours when between Vanuatu and New Caledonia. This would have given it wind gusts of up to 300km/h. It is believed to have been the strongest cyclone recorded in the South Pacific in May, which is very late in the season. It was still producing winds averaging 165km/h with gusts to 205km/h at 19.00EST today, and one in three ocean waves topping 8.5m.
Donna is moving SSE down the eastern side of New Caledonia, so the east and south coasts will fare badly while the three main Loyalty Islands, 100km offshore and close to Donna's track, will fare worst. The cyclone will weaken rapidly overnight and into tomorrow, but not before bringing wind gusts to 175km/h to the Loyalty group and, on current forecast, passing over the top of Maré, the southernmost island in the group.
The central pressure of the cyclone is estimated at 963hPa, so tidal surge flooding is expected at high tide and rainfall over 200mm is forecast in exposed areas. Warnings are on the Météo France Nouvelle Calédonie* and Civil Security* websites (it helps to speak French or use a translator) or the Joint Typhoon Warning Center* site - look for "Donna".
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