Remote Islands and Antarctica in May 2025

Australia's Indian Ocean islands

  • The monthly rainfall total at Christmas Island Aero was 523.6 mm, this was above the May average rainfall of 183.5 mm and the highest May rainfall total since 1978. The highest daily rainfall this month was 145.0 mm on 11 May, this was Christmas Island Aero's fourth-highest May daily rainfall on record.
  • At Christmas Island Aero, the mean maximum and mean minimum temperatures were equal to the May average.
  • The monthly rainfall total at Cocos Island Airport was 194.2 mm, this was close to the May average rainfall of 191.8 mm.
  • At Cocos Island Airport, the mean maximum and mean minimum temperatures were 0.7 and 0.3 °C above the May average, respectively.

Australia's Pacific Ocean islands

Australia's Antarctic and sub-Antarctic territories

  • The strongest wind gust recorded at the Australian Antarctic stations during May was 141 km/h at Casey on the 3rd.
  • Both mean maximum and mean minimum temperatures for May were below average at the Australian Antarctic stations.
  • Casey had its lowest May mean minimum temperature since 2003, at -21.7 °C. The average for May is -18.3 °C.
  • Monthly precipitation at Macquarie Island was 136.2 mm, this was above the May average rainfall of 87.5 mm.
  • The mean maximum and mean minimum temperatures at Macquarie Island were 0.6 and 0.7 °C above the May average, respectively.
  • The strongest wind gust recorded in May at Macquarie Island was 119 km/h on the evening of the 15th.

Highest May total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
May
Norfolk Island Aero 202.8 219.4 in 2004 129.2
Christmas Island Aero 523.6 528.6 in 1978 190.1

note: there may be gaps in the historical record at some sites, so it is possible more recent higher values have gone unreported




Record highest May mean maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Norfolk Island Aero 22.7 22.3 in 2022 87 21.0



Record highest May daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Norfolk Island Aero 21.9 on the 19th 21.5 on 03 May 2004 87 16.2



Record highest May mean minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Norfolk Island Aero 18.4 18.1 in 1999 87 16.2



Lowest May mean minimum temperature for at least 20 years
Observed
(°C)
Most recent
lower
Average for
May
Casey -21.7 -21.9 in 2003 -18.4

note: there may be gaps in the historical record at some sites, so it is possible more recent lower values have gone unreported




Record highest May mean temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Norfolk Island Aero 20.6 20.2 in 2022 87 18.6




Summary statistics for May 2025
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
May
2025
Diff
from
average
Highest for
May
2025
Mean for
May
2025
Diff
from
average
Lowest for
May
2025
Total for
May
2025
Average
for
May
Rank of
May
2025
Fraction of
May
average
Offshore Islands
Lord Howe Island Aero 22.2 +0.6 23.9 7th 17.5 +1.0 13.5 31st 161.0 150.7 average 107%
Norfolk Island Aero 22.7 +1.7 24.7 8th 18.3 +2.1 15.8 28th 202.8 128.6 high 158%
Christmas Island Aero 27.9 0.0 29.8 31st 23.9 0.0 21.7 11th 523.6 183.5 high 285%
Cocos Island Airport 30.0 +0.7 31.8 16th 25.5 +0.3 23.3 24th 194.2 191.8 average 101%
Antarctica and Macquarie Island
Casey -14.5 -3.6 -2.5 3rd -21.7 -3.3 -30.0 27th 23.2 25.6 average 91%
Davis -15.1 -2.4 -5.9 16th -21.4 -2.4 -28.9 22nd 13.5 9.3 high 145%
Macquarie Island 6.6 +0.6 9.4 5th 3.3 +0.7 -1.7 31st 137.0 87.5 high 157%
Mawson -14.4 -0.9 -6.1 18th -19.6 -0.3 -26.7 12th

Daily maximum temperatures for May 2025
Offshore Islands 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Lord Howe Island Aero 21.8 21.9 23.0 22.3 22.6 23.6 23.9 23.8 21.0 21.1 21.9 22.5 22.9 21.9 21.8 21.7 23.4 22.2 20.6 21.6 21.9 22.8 23.0 22.2 22.8 23.1 20.9 21.5 20.5 21.7
Norfolk Island Aero 23.8 21.8 22.2 22.3 23.1 24.0 23.7 24.7 24.5 21.9 21.5 22.8 22.8 22.0 23.1 23.8 23.5 24.5 24.2 20.1 21.7 21.9 21.8 22.4 23.1 22.6 21.7 21.8 22.4 22.1 21.0
Christmas Island Aero 29.1 29.2 28.7 29.5 26.8 28.8 28.6 29.0 28.9 26.2 26.0 28.2 26.6 27.4 29.3 28.3 28.3 27.0 27.5 28.0 27.2 27.4 26.2 26.8 27.4 27.4 27.6 27.4 28.1 28.2 29.8
Cocos Island Airport 30.3 30.4 30.4 29.6 30.2 30.5 30.9 30.6 30.3 30.4 30.0 29.9 28.5 29.5 31.0 31.8 29.3 31.4 27.9 29.3 29.8 29.3 29.1 28.7 29.5 29.1 30.6 29.9 29.2 30.0 31.3
Antarctica and Macquarie Island 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Casey -10.9 -6.0 -2.5 -7.5 -6.5 -7.8 -12.7 -14.4 -15.7 -14.6 -17.7 -19.4 -22.5 -18.7 -17.6 -17.5 -11.9 -19.8 -21.5 -13.6 -18.1 -13.5 -10.1 -16.5 -21.0 -20.6 -9.2 -10.0 -16.7 -17.7 -17.2
Davis -18.4 -15.8 -14.6 -18.0 -16.6 -20.7 -18.9 -18.9 -21.7 -19.7 -15.0 -11.6 -13.5 -19.2 -23.0 -5.9 -6.1 -6.2 -10.1 -15.2 -24.1 -18.8 -8.9 -8.7 -8.5 -10.9 -13.9 -12.4 -12.7 -18.8 -20.9
Macquarie Island 7.3 7.2 7.7 8.3 9.4 8.2 7.5 6.4 7.3 5.7 6.9 6.6 6.2 6.6 7.2 5.7 4.7 6.3 5.8 7.8 6.6 6.6 7.7 7.9 6.5 7.4 5.5 5.7 6.0 3.2 3.4
Mawson -16.1 -15.5 -18.0 -16.2 -17.4 -9.2 -8.9 -11.4 -14.9 -18.5 -21.2 -21.5 -20.0 -15.6 -9.2 -6.7 -7.7 -6.1 -11.3 -17.0 -15.2 -13.8 -14.0 -12.7 -14.2 -11.5 -13.2 -16.7 -17.1 -17.0 -17.5
Values are the maximum temperature, usually in the 24 hours from 9 am on the day indicated,
and typically occurred in the afternoon of that day.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily minimum temperatures for May 2025
Offshore Islands 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Lord Howe Island Aero 16.7 16.3 17.6 18.0 18.1 18.1 19.7 18.0 18.4 16.7 17.2 18.3 18.5 18.3 17.8 19.1 17.9 19.7 17.9 17.2 17.8 19.0 20.0 16.9 13.8 13.9 16.3 17.0 15.2 13.5
Norfolk Island Aero 19.4 17.0 16.4 16.5 16.3 19.5 18.3 20.0 18.8 18.3 17.8 18.3 17.6 18.1 18.2 19.3 20.2 19.9 21.9 19.0 17.3 18.2 17.5 19.0 19.5 20.6 18.0 15.8 16.1 18.3 16.6
Christmas Island Aero 25.3 25.7 25.4 25.3 24.6 23.3 26.1 25.4 26.0 24.1 21.7 22.9 23.5 22.8 23.8 23.8 23.4 23.6 23.2 22.3 24.0 23.1 23.2 22.8 23.5 23.8 23.9 22.7 22.9 24.2 24.6
Cocos Island Airport 23.8 26.3 26.6 25.7 24.9 23.8 27.5 25.7 27.3 26.2 24.7 25.5 25.4 25.2 24.8 26.3 25.8 25.5 25.4 25.3 25.5 25.1 26.3 23.3 24.7 25.0 25.9 26.0 25.8 25.0 25.7
Antarctica and Macquarie Island 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Casey -16.5 -18.5 -15.2 -13.8 -14.9 -9.8 -14.4 -20.5 -19.3 -17.9 -22.2 -23.7 -27.6 -28.8 -25.8 -20.2 -24.9 -24.3 -25.4 -26.2 -24.7 -22.8 -23.4 -24.3 -22.4 -26.8 -30.0 -21.2 -19.0 -24.7 -23.8
Davis -21.1 -22.1 -21.7 -20.5 -21.4 -21.9 -23.7 -23.4 -23.8 -26.1 -24.3 -20.3 -17.8 -22.3 -26.8 -28.2 -25.6 -9.0 -10.6 -17.2 -24.7 -28.9 -26.4 -19.5 -20.1 -13.3 -17.6 -20.7 -16.2 -21.7 -25.4
Macquarie Island 4.8 6.3 2.4 3.6 6.3 6.1 5.9 2.4 2.8 1.3 2.0 4.7 2.5 1.9 4.2 2.4 1.0 0.9 2.7 3.9 4.9 3.8 2.6 5.7 5.5 2.8 3.0 2.8 4.3 0.7 -1.7
Mawson -19.8 -22.1 -21.7 -21.8 -20.5 -22.3 -21.9 -14.4 -16.6 -19.9 -22.7 -26.7 -26.4 -24.1 -21.9 -19.2 -11.3 -11.0 -12.5 -18.3 -21.9 -21.5 -19.1 -17.0 -17.6 -18.7 -16.1 -17.6 -21.6 -22.2 -20.5
Values are the minimum temperature, usually in the 24 hours to 9 am on the day indicated,
and typically occurred that morning.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily rainfall for May 2025
Offshore Islands 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Lord Howe Island (Milky Way) 13.4 5.2 5.6 3.2 2.2 1.8 1.4 - - 1.8 1.4 0.4 - - - 7.4 43.8 3.2 - 38.6 3.2 1.4 4.4 31.6 2.0 - 0.2 6.8 2.6 0.2 -
Lord Howe Island Aero 8.8 6.0 5.8 4.0 2.4 2.6 0.2 - - 1.0 2.0 0.4 - 0.2 1.4 9.4 35.2 2.6 0.2 25.6 4.4 1.4 4.4 19.8 13.2 0.2 - 6.4 2.8 0.6 -
Norfolk Island Aero 0.4 9.6 2.6 2.8 5.2 0.4 28.8 13.4 - 39.8 0.4 0.8 1.0 - - - - 0.8 - 64.0 16.8 - 3.4 - - 3.6 - 8.0 0.8 0.2
Christmas Island Aero - - 4.6 0.2 9.6 21.4 - - 0.2 19.8 145.0 27.4 24.4 42.2 15.6 17.2 18.0 14.8 34.8 67.0 4.2 5.8 6.6 12.8 0.4 6.0 0.2 24.6 0.8 - -
Cocos Island Airport 1.6 1.8 - - 1.6 74.2 0.2 4.8 0.2 0.4 6.4 3.0 3.4 16.0 5.2 2.6 3.6 10.6 18.2 15.6 5.6 5.4 0.2 - 8.8 1.0 - - 0.2 3.6
Antarctica and Macquarie Island 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Casey 2.0 0.6 0.4 1.8 - 0.4 2.4 0.6 0.4 - - - - - - - 0.2 - - - - - - - 0.2 0.2 - 11.4 2.2 0.2 0.2
Davis - - - - - - - - - - - 3.4 3.2 - - - 1.9 - - - - - - 2.6 1.4 - - 1.0 -
Macquarie Island 1.8 3.6 2.4 0.2 6.0 1.0 4.0 2.8 2.2 5.0 7.2 0.6 4.8 3.2 11.6 3.2 6.0 1.4 4.8 1.2 2.4 6.2 3.8 2.0 31.8 2.2 5.0 0.2 1.8 5.2 3.4
Most values are the precipitation in the 24 hours to 9 am on the day indicated. Days marked with → are part of a longer accumulation, which is shown on the final day.
Values over 100 mm have been rounded to the nearest whole millimetre.
Days marked with - have a rainfall report of zero; days left blank have no rainfall report (which often indicates no rain fell).
Rainfalls coloured
according to the amount
0 1.0 5.0 10.0 15.0 25.0 50.0 100 150 200 300 400 600 millimetres

Map of the areas covered by this summary

Notes

The Monthly climate summary, usually published in the first week of the following month, lists the main features of the weather in Remote Islands and Antarctica using the most timely and accurate information available on the date of publication; it will generally not be updated.

This statement has been prepared based on information available on Wednesday 18 June 2025. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

In some situations, some or all of the rainfall is in the form of hail or snow. In these cases, the totals given are for the water equivalent: the depth of liquid water that results from melting any frozen precipitation. There can be significant 'undercatch' of snow in strong winds, meaning the true precipitation can be higher than that reported.

Averages for individual sites are long-term means based on observations from all available years of record, excluding the current year. The length of record can vary widely from site to site. Averages are not shown for sites with fewer than 10 years of record, as they cannot then be calculated reliably.
The median is sometimes more representative than the mean of long-term average rain.

The Rank indicates how rainfall this time compares with the climate record for the site, based on the decile ranking (very low rainfall is in decile 1, low in decile 2 or 3, average in decile 4 to 7, high in decile 8 or 9 and very high is in decile 10).
The Fraction of average shows how much rain has fallen this time as a percentage of the long-term mean.

Where temperature area averages are mentioned, they are derived from the ACORN-SAT dataset.

Information about Australian Indigenous seasonal calendars is available at the Indigenous Weather Knowledge website.

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