Victoria in May 2021: below average rainfall; a warm start and cool end to the month

May rainfall was below average in large areas in the west and north of Victoria, and wetter than average in parts of the east and south-east. Daytime temperatures were warmer than average across the state away from Gippsland. Night-time temperatures were close to average for much of Victoria.

Below average rainfall

  • For Victoria as a whole, rainfall was 16% below the long-term May average of 66 mm.
  • The month was drier than average in large areas of the state's west and north.
  • It was wetter than average in Gippsland and in an area extending west of Melbourne into the Otway Ranges.
  • A cold front and a low pressure system that developed over central Victoria early in the month brought cooler conditions along with showers and thunderstorms. The heaviest falls were reported on the 3rd and 4th in the south-west and east of the state.
  • The highest daily rainfall total in Victoria this May, 116.6 mm, was recorded on the 4th at Aireys Inlet (on the Surf Coast).
  • Another cold front and the associated low pressure system that crossed the state on the 10th resulted in widespread rain with the heaviest falls in the north-east and in Gippsland; parts of East Gippsland reported to 9am on the 12th daily totals in excess of 100 mm.
  • Some sites had their highest May daily rainfall on record on the 4th and 12th.
  • A series of cold fronts between the 13th and 16th brought moderate rainfall to south-eastern Australia, with strong winds, freezing temperatures, and snow in some alpine regions and lower-lying areas.
  • Widespread rainfall was associated with a strong cold front on the 25th; daily totals were generally between 10 and 20 mm, but exceeded 30 mm at many sites in the north-east of Victoria.
  • Some sites had their highest total May rainfall on record or highest total May rainfall for at least 20 years.

A warm start and cool end to the month

  • May saw a mix of cool and mild to warm days, with mean daytime temperatures above average across most of the state.
  • The Victorian mean maximum temperature was 0.93 °C above average, the highest since 2016.
  • May started with warm temperatures across Victoria, with daytime temperatures more than 6 degrees above average on first two days of the month, due to the northerly airstream preceding the approaching cold front.
  • The highest maximum temperature in the state was 29.4 °C at Hopetown Airport on the 2nd.
  • Some sites in eastern and central Victoria had their highest May temperature on record on the 2nd.
  • Hamilton Airport and Aireys Inlet had their warmest May night on record.
  • Cool temperatures generally followed passages of cold fronts. A strong cold front crossed the state on the 14th, leaving winter-like conditions in its wake.
  • Victoria's lowest maximum and minimum temperatures for the month were recorded during this event, with Mount Hotham reaching only −3.9 °C on the 15th and falling to −6.1 °C on the morning of the 16th.
  • Combienbar AWS had its coldest May day on record on the 15th.
  • May finished with cool night-time temperatures as a large, slow-moving high pressure system dominated the state's weather on the last three days of the month.
  • Many sites had their lowest May temperature on record mostly on the 31st.
  • The Victorian mean minimum temperature was 0.21 °C below average.
  • Cerberus had its lowest May mean daily minimum temperature on record.

Floods, snow, strong winds and frost

  • A cold front and low pressure system that crossed the state on 10 May brought showers and thunderstorms. Moderate flooding was observed on the 11th along the Cann River around Chandler's Creek and in the Genoa River.
  • A cold front on the 14th brought snow to Lake Mountain, Mount Hotham Mount Buller and Mount Baw Baw.
  • The strongest winds in May were recorded on the 16th and 25th with gusts of 126 km/h at Wilsons Promontory Lighthouse and Mount Hotham respectively.
  • Widespread frost was observed in many parts of Victoria on the last several days of the month.

Further information

Media
(03) 9669 4057

Extremes in May 2021
Hottest day 29.4 °C at Hopetoun Airport on the 2nd
Warmest days on average 19.9 °C at Mildura Airport
19.9 °C at Walpeup Research
Coolest days on average 4.5 °C at Mount Hotham
Coldest day -3.9 °C at Mount Hotham on the 15th
Coldest night -6.1 °C at Mount Hotham on the 16th
Coolest nights on average 0.1 °C at Mount Hotham
Warmest nights on average 12.4 °C at Gabo Island Lighthouse
Warmest night 18.8 °C at Cape Otway Lighthouse on the 2nd
Warmest on average overall 15.1 °C at Gabo Island Lighthouse
Coolest on average overall 2.3 °C at Mount Hotham
Wettest overall 276.4 mm at Haines Junction (Mount Sabine)
Wettest day 116.6 mm at Aireys Inlet on the 4th
Strongest wind gust 126 km/h at Wilsons Promontory Lighthouse on the 16th
126 km/h at Mount Hotham on the 25th

Maps
ObservedAnomalyDecile rank
Total
rainfall
Map of Rainfall totals Map of Percentage of normal rainfall Map of Rainfall deciles
Mean
daily
maximum
temperatures
Map of Mean maximum temperature Map of Anomaly in mean maximum temperature Map of Decile rank of mean maximum temperature
Mean
daily
minimum
temperatures
Map of Mean minimum temperature Map of Anomaly in mean minimum temperature Map of Decile rank of mean minimum temperature

Click on a map to show it full size in a pop-up window


Record highest May daily rainfall
New record
(mm)
Old
record
Years of
record
Cobden (Post Office) 51.6 on the 4th 43.7 on the 14th in 1945 128
Durdidwarrah 58.6 on the 4th 56.1 on the 25th in 1952 127
Avalon Airport 38.2 on the 4th 32.0 on the 3rd in 1979 42
Sheoaks 40.8 on the 4th 38.2 on the 10th in 2019 27
Aireys Inlet 116.6 on the 4th 56.4 on the 10th in 2019 26
Combienbar AWS 101.8 on the 12th 52.8 on the 31st in 2010 26
Mount Moornapa 57.4 on the 12th 47.0 on the 5th in 2000 26
Warrnambool Airport NDB 38.6 on the 4th 37.0 on the 30th in 2007 23
Avon River @ The Channel 39.6 on the 12th 20.0 on the 25th in 2012 21
Boonah 53.6 on the 4th 41.6 on the 11th in 2018 21
Haines Junction (Mount Sabine) 85.2 on the 4th 55.4 on the 1st in 2006 20
Lorne (Mount Cowley) 61.8 on the 12th 40.6 on the 10th in 2019 20



Record highest May total rainfall
New record
(mm)
Old
record
Years of
record
Average for
May
Aireys Inlet 163.2 145.6 in 2019 26 57.5
Combienbar AWS 212.2 203.0 in 2006 26 68.0
Orbost 165.6 122.2 in 2011 21 57.9
Avon River @ The Channel 94.8 57.0 in 2012 20 29.7
Lorne (Mount Cowley) 219.4 214.4 in 2019 20 114.9
Wonnangatta River @ Waterford 87.6 79.8 in 2018 20 36.2

Highest May total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Average for
May
Ensay 123.6 134.7 in 1981 49.8
Meerlieu (Springvale West) 140.4 180.0 in 1983 49.1
Dargo 103.2 128.1 in 1987 49.3
Bruthen (Post Office) 114.2 119.8 in 1987* 58.7
Melbourne Airport 67.2 78.4 in 2000 40.6
Stratford 73.8 93.7 in 2000 45.0
Toorourrong Reservoir (Toorourrong) 96.8 152.2 in 2000 67.3
Viewbank 82.4 144.0 in 2000 54.7
Giffard 72.2 113.8 in 2000* 45.1
Nicholson Winery 105.6 118.6 in 2000* 43.4

* note: there are gaps in the historical record at this site, so it is possible a higher value has gone unreported




Record highest May temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Strathbogie 23.5 on the 6th 23.0 on the 3rd in 2018 44 14.4
Bendigo Airport 26.4 on the 2nd 26.3 on the 7th in 2002 30 16.6
Cerberus 25.6 on the 2nd = 25.6 on the 9th in 2013 30 16.6
Rhyll 23.6 on the 2nd = 23.6 on the 1st in 1993 30 16.3
Avalon Airport 28.0 on the 2nd = 28.0 on the 8th in 2002 27 17.3
Shepparton Airport 26.7 on the 2nd 26.0 on the 3rd in 2018 25 17.6
Swan Hill Aerodrome 29.0 on the 2nd 28.0 on the 8th in 2002 25 18.8



Record lowest May daily maximum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Combienbar AWS 5.9 on the 15th 6.1 on the 13th in 2012 27 14.4



Record highest May daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Hamilton Airport 16.1 on the 2nd 15.5 on the 1st in 1997 38 6.6
Aireys Inlet 17.5 on the 2nd 17.2 on the 9th in 2002 30 9.9



Record lowest May temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Ouyen (Post Office) -1.0 on the 31st = -1.0 on the 16th in 1999 65 7.2
Kyabram -2.7 on the 31st -2.5 on the 31st in 2002 56 6.1
Morwell (Latrobe Valley Airport) -2.8 on the 31st -2.6 on the 24th in 2008 38 6.5
Cerberus -1.1 on the 31st = -1.1 on the 11th in 1992 30 8.5
Port Fairy AWS 0.4 on the 31st 2.0 on the 31st in 2011 30 9.2
Yarrawonga -1.9 on the 29th -1.6 on the 28th in 2006 29 6.1
Redesdale -2.3 on the 31st -2.2 on the 16th in 1999 28 5.2
Avalon Airport -1.3 on the 31st -0.7 on the 31st in 2006 27 7.7
Coldstream -3.7 on the 22nd -3.2 on the 20th in 2005 27 5.7
Horsham Aerodrome -4.3 on the 30th -4.0 on the 30th in 2006 24 5.3
Mount Baw Baw -5.8 on the 29th -5.0 on the 28th in 2000 24 1.5
Warrnambool Airport NDB -1.7 on the 31st -0.7 on the 19th in 2005 23 7.5
Viewbank -0.4 on the 31st -0.3 on the 10th in 2011 22 8.0
Orbost 1.5 on the 31st 2.2 on the 24th in 2008 21 8.4



Record lowest May mean daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
May
Cerberus 7.3 7.4 in 2013 29 8.5



Summary statistics for May 2021
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
May
2021
Diff
from
average
Highest for
May
2021
Mean for
May
2021
Diff
from
average
Lowest for
May
2021
Total for
May
2021
Average
for
May
Rank of
May
2021
Fraction of
May
average
North Mallee (district 76)
Mildura Airport 19.9 +0.8 28.9 2nd 6.6 -0.8 -1.4 30th 8.0 24.8 low 32%
Ouyen (Post Office) 19.7 +0.8 28.9 2nd 6.7 -0.5 -1.0 31st 14.8 31.2 low 47%
Walpeup Research 19.9 +1.5 29.1 2nd 7.2 -0.6 1.9 31st 10.0 30.1 low 33%
South Mallee (district 77)
Hopetoun Airport 19.6 +0.8 29.4 2nd 5.1 -1.0 -3.2 31st 10.6 26.1 v low 41%
Swan Hill Aerodrome 19.6 +0.8 29.0 2nd 5.7 -0.7 -1.0 31st 12.4 25.7 low 48%
North Wimmera (district 78)
Kellalac (Warracknabeal Airport) 18.9   28.1 2nd 5.7   -1.6 31st 21.6
Nhill Aerodrome 18.3 +0.5 25.9 1st 6.4 -0.4 0.4 6th 14.0 29.9 low 47%
South Wimmera (district 79)
Edenhope Airport 17.0 +0.3 24.1 1st 7.0 -0.2 -1.3 30th 33.4 46.9 average 71%
Grampians (Mount William) 9.3 +0.9 17.6 6th 3.7 +0.1 -0.6 15th 136.4 133.6 average 102%
Horsham Aerodrome 18.1 +0.5 25.4 2nd 4.1 -1.2 -4.3 30th 22.0 34.5 average 64%
Kanagulk 17.0 +0.5 24.5 7th 5.5 -1.0 -4.0 30th 24.2 44.4 low 55%
Longerenong 18.2 +1.1 25.9 2nd 5.4 -0.5 -1.7 29th 24.0 42.7 low 56%
Pyrenees (Ben Nevis) 11.6 +0.7 19.9 2nd 5.4 0.0 0.6 29th 95.0 77.5 high 123%
Stawell Aerodrome 16.3 +0.1 25.5 2nd 6.1 -0.3 -1.2 30th 36.4 42.9 average 85%
Lower North (district 80)
Charlton 18.5 +0.5 28.1 2nd 6.0 -0.4 -1.2 30th 34.0 35.2 average 97%
Echuca Aerodrome 19.1 +1.5 27.3 2nd 5.7 -0.9 -1.5 31st 14.7 40.4 low 36%
Kerang 19.1 +1.0 28.1 2nd 6.5 -0.2 -0.1 29th 17.6 35.8 low 49%
Kyabram 18.7 +1.4 26.5 2nd 5.3 -0.8 -2.7 31st 15.8 41.9 low 38%
Upper North (district 81)
Bendigo Airport 17.4 +0.8 26.4 2nd 4.9 -0.4 -1.6 31st 54.2 47.2 average 115%
Shepparton Airport 18.8 +1.2 26.7 2nd 5.4 -0.2 -2.6 31st 35.0 34.3 average 102%
Tatura Inst Sustainable Ag 18.3 +1.1 25.9 2nd 5.0 -0.8 -3.0 31st 22.8 44.4 low 51%
Yarrawonga 18.9 +0.8 26.5 2nd 5.8 -0.3 -1.9 29th 44.6 35.9 average 124%
Lower Northeast (district 82)
Benalla Airport 18.3 +0.9 25.8 2nd 4.6 -0.6 -3.3 16th 21.2 46.3 v low 46%
Dartmouth Reservoir 16.4 +0.5 24.0 7th 4.7 0.0 -2.0 31st 77.6 86.0 average 90%
Hunters Hill 12.0 +0.2 19.5 6th 5.7 +0.3 -0.4 16th 109.0 99.4 average 110%
Rutherglen Research 18.5 +1.5 26.3 6th 3.3 -1.0 -4.7 30th 48.4 51.5 average 94%
Strathbogie 15.4 +1.0 23.5 6th 2.9 -0.8 -5.2 31st 83.4 95.3 average 88%
Wangaratta Aero 18.6 +1.2 25.2 6th 4.1 -0.2 -4.2 31st 37.4 56.4 average 66%
Upper Northeast (district 83)
Falls Creek 5.5 -0.5 12.9 7th 0.7 +0.1 -5.9 16th 210.2 101.6 high 207%
Mount Buller 6.0 -0.1 13.3 6th 1.0 0.0 -5.0 16th 142.4 141.9 average 100%
Mount Hotham 4.5 -0.1 11.4 7th 0.1 +0.2 -6.1 16th 155.2 139.1 average 112%
Omeo 14.4 0.0 21.5 7th 2.5 -0.3 -5.7 31st 98.0 38.8 high 253%
East Gippsland (district 84)
Combienbar AWS 14.3 -0.1 21.8 1st 8.0 +0.3 2.1 16th 212.2 68.0 highest 312%
Gabo Island Lighthouse 17.7 +0.8 23.4 10th 12.4 +1.2 7.8 16th 135.8 98.1 high 138%
Gelantipy 13.0 0.0 18.9 1st 4.8 -0.1 -0.9 30th 98.0 47.6 v high 206%
Lakes Entrance (Eastern Beach Road) 17.4 -0.5 25.4 2nd 8.3 -0.2 0.0 31st 103.8 45.9 v high 226%
Mallacoota 17.9 +0.3 24.4 2nd 10.1 +0.8 4.0 31st 130.8 83.3 high 157%
Mount Nowa Nowa 15.9 0.0 24.2 2nd 8.7 0.0 4.1 16th 168.4 60.7 v high 277%
Orbost 18.0 +0.2 26.0 2nd 8.6 +0.2 1.5 31st 165.6 57.9 highest 286%
West Gippsland (district 85)
Bairnsdale Airport 17.4 -0.2 26.3 2nd 6.4 -0.3 -1.6 30th 74.4 44.7 high 166%
Corner Inlet (Yanakie) 16.3   23.2 2nd 7.1   -0.3 22nd 64.6
East Sale 17.4 +0.5 25.6 1st 6.0 -0.3 -2.2 31st 81.2 50.1 high 162%
East Sale Airport 17.6   24.7 1st 6.0   -2.0 31st 76.6
Morwell (Latrobe Valley Airport) 17.2 +0.3 25.4 2nd 5.4 -1.1 -2.8 31st 53.4 55.3 average 97%
Mount Baw Baw 6.5 +0.1 13.2 1st 2.0 +0.5 -5.8 29th 139.4 125.4 average 111%
Mount Moornapa 15.1 +0.1 24.3 2nd 7.7 -0.2 2.0 30th 120.6 48.6 high 248%
Nilma North (Warragul) 16.4   25.1 2nd 5.9   -3.5 31st 67.4
Pound Creek 17.2 +0.2 25.4 2nd 6.5 -1.7 -0.6 30th 93.4 98.1 average 95%
Wilsons Promontory Lighthouse 14.9 -0.1 20.5 2nd 11.4 +0.3 7.4 15th 111.8 114.2 average 98%
Yarram Airport 17.1 -0.2 25.3 2nd 6.1 -0.7 -3.0 22nd 70.4 49.5 high 142%
East Central (district 86)
Cerberus 17.3 +0.7 25.6 2nd 7.3 -1.2 -1.1 31st 44.8 70.1 low 64%
Coldstream 17.1 +0.5 25.1 2nd 4.5 -1.2 -3.7 22nd 74.6 69.3 average 108%
Essendon Airport 17.4 +1.1 25.8 2nd 7.7 -0.2 0.4 22nd 65.8 49.0 high 134%
Ferny Creek 13.4 +0.5 21.2 2nd 7.8 0.0 3.0 16th 115.0 132.9 low 87%
Frankston (Ballam Park) 16.8   24.9 2nd 8.6   1.9 31st 58.2
Melbourne (Olympic Park) 17.8   26.0 2nd 8.9   1.7 30th 66.4
Melbourne Airport 17.3 +0.6 26.4 2nd 7.3 -1.0 1.3 30th 67.2 40.6 v high 166%
Moorabbin Airport 17.4 +0.4 26.4 2nd 8.3 -0.4 0.6 31st 52.8 68.7 average 77%
Rhyll 16.8 +0.5 23.6 2nd 10.3 -0.5 5.3 30th 65.8 75.2 average 88%
Scoresby Research Institute 17.3 +0.9 25.1 2nd 7.7 -0.6 0.0 30th 67.6 86.9 low 78%
Viewbank 17.5 +0.3 25.8 2nd 7.2 -0.8 -0.4 31st 82.4 54.7 v high 151%
West Central (district 87)
Avalon Airport 17.4 +0.1 28.0 2nd 6.8 -0.9 -1.3 31st 58.4 37.8 high 154%
Breakwater (Geelong Racecourse) 17.4   27.8 2nd 7.5   0.3 31st 56.4 50.4 average 112%
Laverton RAAF 17.7 +0.8 26.7 2nd 7.7 -0.1 -0.3 31st 58.6 46.0 high 127%
Sheoaks 15.8 +0.2 25.3 2nd 6.7 -0.6 -0.8 31st 74.6 39.6 v high 188%
North Central (district 88)
Castlemaine Prison     18.2 23rd 4.9 -0.5 -0.5 30th 34.7 57.8 low 60%
Eildon Fire Tower 14.0 +0.8 22.2 2nd 6.5 -0.1 1.3 29th 65.6 55.7 average 118%
Lake Eildon 16.7 +0.6 24.7 2nd 5.7 -0.3 -1.2 29th 76.0 78.4 average 97%
Mangalore Airport 17.8 +1.1 26.6 2nd 4.7 -1.3 -3.3 31st 51.2 53.5 average 96%
Maryborough 16.4 +0.2 25.4 2nd 4.9 -1.2 -1.4 30th 37.6 49.1 average 77%
Puckapunyal Lyon Hill (Defence) 17.3   25.3 2nd 6.9   1.2 31st 37.4
Puckapunyal West (Defence) 16.6   24.8 2nd 6.8   0.8 31st 50.6
Redesdale 17.2 +1.1 25.5 2nd 4.1 -1.1 -2.3 31st 51.8 55.7 average 93%
Wallan (Kilmore Gap) 13.7 +0.9 21.9 2nd 6.7 -0.2 2.8 15th 96.8 59.8 high 162%
Western Plains (district 89)
Ararat Prison 15.8 +0.3 25.5 2nd 5.0 -0.6 -1.7 30th 51.0 54.9 average 93%
Ballarat Aerodrome 14.3 +0.6 23.1 2nd 5.0 -0.7 -1.9 22nd 65.2 64.6 average 101%
Westmere 15.9 +0.2 26.1 2nd 5.2 -1.3 -2.5 30th 49.0 57.8 average 85%
West Coast (district 90)
Aireys Inlet 16.2 -0.1 25.5 2nd 9.9 0.0 5.0 31st 163.2 57.5 highest 284%
Cape Nelson Lighthouse 16.3 +0.1 22.0 1st 11.0 +0.2 5.4 31st 61.4 73.5 average 84%
Cape Otway Lighthouse 15.9 +0.3 23.6 2nd 10.8 +0.7 4.0 31st 78.2 91.5 average 85%
Casterton 16.6 +0.4 22.0 1st 6.5 -0.7 -1.1 30th 38.4 68.7 low 56%
Colac (Mount Gellibrand) 15.5 +0.4 24.7 2nd 7.9 -0.1 4.1 21st 56.6 46.8 average 121%
Dartmoor 16.6 +0.3 22.1 1st 7.2 -0.3 -0.9 31st 62.2 86.7 low 72%
Hamilton Airport 15.5 -0.1 22.3 7th 6.3 -0.3 0.5 31st 52.6 54.8 average 96%
Mortlake Racecourse 16.5 +0.3 24.0 2nd 5.8 -0.9 -2.8 30th 68.0 58.5 high 116%
Port Fairy AWS 16.9 +0.1 23.7 1st 8.9 -0.3 0.4 31st 71.4 69.6 average 103%
Portland (Cashmore Airport) 16.2 +0.3 21.1 1st 8.4 0.0 0.7 31st 69.8 83.7 average 83%
Warrnambool Airport NDB 16.3 -0.2 23.0 1st 6.8 -0.7 -1.7 31st 102.2 76.4 high 134%

Notes

The Monthly climate summary, generally published on the first working day of each month, lists the main features of the weather in Victoria using the most timely and accurate information available on the date of publication; it will generally not be updated. More extensive discussion of significant weather events, along with later information and data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review.

This statement has been prepared based on information available at 10 am on Tuesday 1 June 2021. 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, which vary widely from site to site. They are not shown for sites with less 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.

Further information

Media
(03) 9669 4057

Climate