Melbourne Metropolitan Area and Environs in March 2010: Rainfall much more than that usually received.

The city of Melbourne's total rainfall for the month was 79 mm, this being much more than that usually recorded (normal 50.4 mm, percentage of normal received during the past month 157%).

Overnight minimum temperatures were much warmer than those historically experienced and averaged 16.3C (departure from normal 3.1C), partly on account of the heat island effect (cities are usually warmer than their rural surroundings, especially at night, because of heat stored in bricks and concrete and trapped between close-packed buildings).

Daytime maximum temperatures were also much warmer than those usually experienced and averaged 26.2C (departure from normal 2.3C).

The maximum temperature in the city has now reached  20C on every day since 9 December last year (113 days), the longest string of 20C+ days on record (previous record: 78 days, set between 29 December 2000 and 16 March 2001).

On 6 March, a developing low pressure system with an associated low pressure trough to the west of Victoria generated showers and thunderstorms in the west of the State during the morning, which spread eastward and intensified during the early afternoon. Severe thunderstorms developed to the northwest of the Melbourne Metropolitan Area and moved through the city from early afternoon progressing to the eastern suburbs and then into West Gippsland later in the afternoon.

The severe thunderstorms were associated with large hail and heavy rain resulting in widespread flash flooding and water and hail damage to property. Hail of 10cm was reported at 3.30 pm at Ferntree Gully, with 7cm hail at 3:30pm Ferny Creek, and 5cm hail at Blackburn and Glen Iris. Historically, the only comparable report of such large hail in Melbourne was from 14 November 1901 when "an egg shaped mass of ice (was) picked up in Victoria Parade (that) had dimensions 7 cm x 4.5 cm x 4 cm."

 Details Extremes Records Summaries Important notes the top

Selected Melbourne suburbs

In the suburb of Essendon, which is located some 15 kilometres to the northwest of the city centre, overnight minimum temperatures were much warmer than those usually experienced and averaged 14.6C (departure from normal 2.3C). Daytime maximum temperatures were warmer than those usually experienced and averaged 25.2C (departure from normal 1.3C). Total rainfall for the month was 82 mm, this being much more than that usually recorded (normal 39.9 mm, percentage of normal received during the past month 206%).

The suburb of Laverton is located some 30 kilometres to the southwest of the city centre, and is often under the drying influence of the rain shadow from the ranges of western Victoria. Here, overnight minimum temperatures were much warmer than those usually experienced and averaged 14.6C (departure from normal 2.1C). Daytime maximum temperatures were much warmer than those usually experienced and averaged 25.2C (departure from normal 1.6C). Total rainfall for the month was 70.8 mm, this being much more than that usually recorded (normal 35.6 mm, percentage of normal received during the past month 199%).

In the suburb of Bundoora, which is located some 20 kilometres to the northeast of the city centre, overnight minimum temperatures were much warmer than those usually experienced and averaged 14.4C (departure from normal 2.1C). Daytime maximum temperatures were warmer than those usually experienced and averaged 25.6C (departure from normal 1.4C). Total rainfall for the month was 76.2 mm, this being much more than that usually recorded (normal 44.5 mm, percentage of normal received during the past month 171%).

In the suburb of Moorabbin, which is located some 20 kilometres to the southeast of the city centre, overnight minimum temperatures were much warmer than those usually experienced and averaged 14.5C (departure from normal 1.7C). Daytime maximum temperatures were warmer than those usually experienced and averaged 24.9C (departure from normal 1.2C). Total rainfall for the month was 58.4 mm, this being slightly more than that usually recorded (normal 44.8 mm, percentage of normal received during the past month 130%).

Synoptic summary

The generally warmer than normal conditions were associated with extended periods of northerly flow across eastern Australia, because of the tendency for high pressure systems to be located over the Tasman Sea, where Mean Sea Level pressures averaged more than 4 hPa above the long term average.

The generally wetter than normal conditions may be linked to the frequent incursions of moisture brought by ex-tropical cyclones, which were steered over inland Queensland by the easterly flow on the northern flank of the Tasman Sea anticyclones.

Mean Sea Level pressures were well above normal over Victoria for much of the month. Melbourne's reading of 1037.6 hPa at 9.53am on the 12th was the highest on record for March. 

Rainfall

Some sites had their highest total March rainfall for at least 10 years.

Temperature

Some sites had their highest March mean daily minimum temperature on record.

Some sites had their highest March mean daily minimum temperature for at least 10 years.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in March 2010
Hottest day 34.2 C at Laverton RAAF on the 17th
Warmest days on average 26.2 C at Melbourne Regional Office
Coolest days on average 21.0 C at Ferny Creek (Dunns Hill)
Coldest day 13.2 C at Ferny Creek (Dunns Hill) on the 10th
Coldest night 4.9 C at Coldstream on the 2nd
Coolest nights on average 11.8 C at Coldstream
Warmest nights on average 16.3 C at Melbourne Regional Office
Warmest night 23.0 C at Melbourne Regional Office on the 19th
Wettest overall 86.2 mm at Melbourne Airport
Driest overall 46.4 mm at Avalon Airport
Wettest day 46.4 mm at Melbourne Airport on the 7th
Highest wind gust 102 km/h at Melbourne Airport on the 6th

Highest total March rainfall for at least 10 years
Total rainfall
for March 2010 (mm)
Most recent higher
for March
Years since
higher
Average for
March
Essendon Airport 82.0 154.1 in 1970 24 39.9
Bundoora (Latrobe University) 76.2 99.4 in 1999 11 44.5
Coldstream 82.4 124.8 in 1999 11 48.0



Record highest March mean daily minimum temperature
Mean daily minimum
temperature
for March 2010 (C)
Previous highest
for March
Years of
record
Average for
March
Essendon Airport 14.6 14.5 in 1956 40 12.3
Coldstream 11.8 10.8 in 2000 15 9.2
Viewbank (ARPANSA) 14.2 13.2 in 2007 10 12.4

Highest March mean daily minimum temperature for at least 10 years
Mean daily minimum
temperature
for March 2010 (C)
Most recent higher
for March
Years since
higher
Average for
March
Laverton RAAF 14.6 15.3 in 1974 36 12.5
Melbourne Regional Office 16.3 16.8 in 1974 36 13.2
Bundoora (Latrobe University) 14.4 14.5 in 1983 23 12.3
Cerberus 13.9 14.1 in 1992 18 12.3
Cranbourne Botanic Gardens 13.4 13.9 in 1992 18 12.3
Melbourne Airport 14.4 14.4 in 1992 18 12.6
Moorabbin Airport 14.5 14.5 in 1992 18 12.8
Scoresby Research Institute 13.9 14.4 in 1992 16 12.4
Avalon Airport 13.8 13.9 in 2000 10 12.2
Ferny Creek (Dunns Hill) 12.6 12.7 in 2000 10 11.1



Summary statistics for March 2010
Maximum temperatures
for March
(C)
Minimum temperatures
for March
(C)
Rainfall
for March
(millimetres)
Mean for
March
2010
Diff
from
average
Highest for
March
2010
Mean for
March
2010
Diff
from
average
Lowest for
March
2010
Total for
March
2010
Average
for
March
Rank of
March
2010
Fraction of
March
average
Avalon Airport 25.1 +1.0 34.1 4th 13.8 +1.6 8.9 23rd 46.4 28.7 high 162%
Bundoora (Latrobe University) 25.6 +1.4 33.2 17th 14.4 +2.1 9.1 12th 76.2 44.5 high 171%
Cerberus 24.3 +1.5 32.7 4th 13.9 +1.6 8.7 14th 62.0 45.3 average 137%
Coldstream 26.1 +1.0 32.2 18th 11.8 +2.6 4.9 2nd 82.4 48.0 high 172%
Cranbourne Botanic Gardens 24.8 +1.4 32.5 17th 13.4 +1.1 9.0 12th 66.5 41.2 high 161%
Essendon Airport 25.2 +1.3 33.5 17th 14.6 +2.3 10.1 12th 82.0 39.9 v high 206%
Ferny Creek (Dunns Hill) 21.0 +1.1 27.4 17th 12.6 +1.5 6.9 1st
Laverton RAAF 25.2 +1.6 34.2 17th 14.6 +2.1 8.5 22nd 70.8 35.6 high 199%
Melbourne Airport 25.0 +1.0 32.5 17th 14.4 +1.8 9.1 31st 86.2 37.3 v high 231%
Melbourne Regional Office 26.2 +2.3 33.0 17th 16.3 +3.1 11.1 12th 79.0 50.4 high 157%
Moorabbin Airport 24.9 +1.2 33.1 17th 14.5 +1.7 8.7 12th 58.4 44.8 high 130%
Scoresby Research Institute 25.4 +1.4 32.0 17th 13.9 +1.5 6.8 11th 86.0 53.9 high 160%
Viewbank (ARPANSA) 26.0 +0.7 32.8 17th 14.2 +1.8 8.4 12th 70.0 41.6 high 168%

Notes

A Monthly Climate Summary is prepared to list the main features of the weather in Melbourne Metropolitan Area and Environs using the most timely and accurate information available on the date of publication; it will generally not be updated. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.

This statement has been prepared based on information available at 11 am on Thursday 1 April 2010. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages 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.

Further information

Media
(03) 9669 4057
Enquiries