Monday, 2 May 2011 - Monthly Climate Summary for Tasmania - Product code IDCKGC17R0
Tasmania in April 2011: Wet continues in the east
It was another wet month in the east of Tasmania after very heavy falls between the 10th and 13th. In the west it was drier than usual, despite cold fronts that brought some rain. Temperatures were were mostly slightly warmer than usual, but neither extremely hot nor extremely cold.
- 153 mm in a day and 57 mm in an hour at Eddystone Point
- Wettest April day on record in parts of the southeast
- Hobart's wettest day in over 50 years
Extreme rainfall in the east
Heavy rain fell in eastern Tasmania between the 10th and 13th as an active and complex low pressure system moved nearby, bringing the fourth heavy rain event to the state for the year. The heaviest rain fell in the far northeast overnight on the 10-11th, with Eddystone Point receiving 57 mm in the hour around midnight and 153 mm in the 24 hours to 9 am on the 11th. Rainfall of this intensity is expected to occur less than once every 100 years in this region.
The heaviest rain moved slowly southwards, affecting the area around St Helens on the 11th and 12th (with the airport receiving 176 mm in 2 days) and the southeast of Tasmania from the afternoon of the 12th until the morning of the 13th. Hastings Chalet (125 mm), Mount Nelson (124 mm), Leslie Vale (112 mm) and Kingston (107 mm) were some of the sites in the southeast that had over 100 mm in a day, and several sites had their wettest April day on record.
not as damaging as the events in January or March, the rain did cause
local flash flooding and minor to moderate flooding of some rivers.
Very wet in the east but drier than usual in the west
Heavy rain between the 10th and 13th ensured it was a very wet April in eastern Tasmania with many sites having at least double their April average. Eddystone Point (268 mm) and Gladstone (247 mm) reported the most rain for the month, both having their second-wettest April on record. They also had their wettest April in over 20 years along with Bicheno, Huonville and Scamander.
The west was drier than usual despite cold fronts bringing light to moderate falls between the 1st and 4th and again from the 19th to 24th. Zeehan (99 mm) had only half of its normal April rainfall. Still, most areas reported over 50 mm except for the Derwent Valley between New Norfolk and Ouse, and the Midlands around Campbell Town and Cressy. Ouse was the driest site with a total of 27.6 mm for the month.
The heavy rain in the east added to record falls during January and March (and local heavy falls in February) to give some sites, particularly in the northeast, their wettest start to a year on record. North-eastern Tasmania has already had a much wetter than usual autumn, and Gladstone (511 mm) and Pyengana (589 mm) have already had their wettest autumn on record although there is still a month to go.
Temperatures mostly near normal
There were no great extremes of temperatures during April: most days and nights were not too far from normal. Averaged over the month, minimum temperatures were just slightly warmer than usual, while maximum temperatures were warmer than usual in the west but cooler than usual in the east.
The warmest days occurred between the 5th and 9th as northerly winds blew over the state, pushing Bushy Park's temperature up to 26.5 °C on the 8th. The coolest days for the month followed between the 11th and 15th as rain fell in a southeast to southerly airstream, but the coldest day overall was at Mount Wellington on the 22nd when it only reached 3.6 °C in snowy weather.
Cool and warm nights were interspersed through the month. Cloud, rain and wind meant the morning of the 9th was one of the warmest with several sites not falling below 15 °C. The minimum temperature at King Island on this morning was 16.6 °C. A week later, the morning of the 16th was one of the coldest with light winds and clear skies allowing Liawenee's temperature to dip to -4.7 °C.
Hobart's wettest day in 50 years and wettest April since 1996
Hobart had its wettest day in over 50 years when 78.8 mm fell in the 24 hours to 9 am on the 13th. The last time there was so much rain in a day was 23 April 1960. Another 44 mm was reported between the 10th and 15th, and combined with few millimetres on other days to give a monthly total of 125 mm. This was well above the average of 52 mm, and made it Hobart's wettest April since 1996.
Temperatures in Hobart were warm between the 7th and 9th, with 3 days in a row over 23 °C suggesting a return to summer conditions. But a cold week followed, with no day warmer than 14.4 °C between the 11th and 15th, and a minimum of just 5.0 °C on the 16th. The last week of the month was warmer again with daytime temperatures around 20 °C. The average minimum and maximum temperatures for the month were 10.0 °C and 18.1 °C respectively, around a degree warmer than normal.
|Extremes in April 2011|
|Hottest day||26.5 °C at Bushy Park (Bushy Park Estates)
on the 8th
|Warmest days on average||19.1 °C at Eddystone Point|
|Coolest days on average||9.3
°C at Mount
|Coldest day||3.6 °C at Mount Wellington on
|Coldest night||-4.7 °C at Liawenee on the 16th
|Coolest nights on average||2.2 °C at Liawenee
|Warmest nights on average||13.0 °C at Hogan Island
|Warmest night||16.6 °C at King Island Airport
on the 9th
|Warmest on average overall||15.4 °C at Hogan Island
|Coolest on average overall||6.3
°C at Mount
|Wettest overall||268.0 mm at Eddystone Point
|Driest overall||27.6 mm at Ouse Fire Station
|Wettest day||153.2 mm at Eddystone Point on
|Highest wind gust||139 km/h at Macquarie Island on the 24th|
Click on a map to show it full size in a pop-up window
|Record highest April daily rainfall|
Highest daily rainfall
in April 2011 (mm)
|Taroona (Taroona Crescent) **||97.2||on the 13th||39.0||on the 18th in 1996||48|
|Geeveston (Cemetery Road)||65.2||on the 13th||40.0||on the 2nd in 1996||40|
|Risdon Vale (Poplar Road)||88.4||on the 13th||55.9||on the 21st in 1965||32|
|Blackmans Bay Treatment Plant||92.2||on the 13th||50.8||on the 18th in 1996||30|
|Bull Bay (Lauriston)||75.0||on the 13th||52.0||on the 18th in 1996||28|
|Nugent (Twilight Valley)||80.6||on the 13th||76.4||on the 24th in 2001||28|
|Tea Tree (The Point)||74.4||on the 13th||52.2||on the 17th in 1996||25|
|Richmond (Strathayr)||55.2||on the 13th||47.0||on the 17th in 1996||23|
|Highest total April rainfall for at least 20 years|
for April 2011 (mm)
Most recent April
at least this wet
|Gladstone (Old Post Office)||247.0||295.1||in 1929||70||73.9|
|Eddystone Point||268.0||308.7||in 1960||50||66.6|
|Bicheno (Council Depot)||151.4||192.5||in 1960||44||60.2|
|Huonville (Tutton Avenue)||96.2||160.2||in 1965||38||52.9|
|Record highest total January to April rainfall|
for January to April 2011 (mm)
for January to April
January to April
|Pioneer (Main Road)||705.3||540.7||in 1929||107||241.7|
|Eddystone Point||566.2||519.4||in 1946||100||218.7|
|Gladstone (Old Post Office)||776.0||605.0||in 1977||80||235.6|
|Devonport Airport||355.2||338.0||in 1973||47||185.9|
|Pyengana (Forest Lodge Road)||931.8||579.2||in 2004||46||333.6|
|Forthside Research Station||444.8||433.0||in 1989||45||228.1|
|Barrington Post Office||498.1||457.0||in 1989||44||257.1|
|Scottsdale (West Minstone Road)||421.8||371.4||in 1989||40||232.9|
|King Island Airport||315.0||275.8||in 1983||37||177.2|
|Cape Grim BAPS (Comparison)||300.4||278.4||in 1990||24||181.9|
|Deviot Jetty||366.4||316.8||in 1996||20||206.4|
|Summary statistics for April 2011|
|Northern (district 91)|
|Bridport (Sea View Villas)||17.8||-0.3||20.8||9th||9.9||+0.5||6.0||16th||138.4||62.7||v high||221%|
|Burnie (Round Hill)||18.1||+0.4||20.5||4th||10.8||+0.8||8.2||2nd||62.6||74.9||average||84%|
|Cape Grim BAPS (Comparison)||16.6||+0.2||20.4||8th||11.6||+0.2||8.3||25th||60.4||67.5||average||89%|
|Cressy Research Station||17.7||-0.5||22.1||9th||6.4||+0.9||-0.3||16th||49.2||45.4||average||108%|
|Launceston (Ti Tree Bend)||18.7||-0.1||22.9||9th||7.7||+0.2||2.6||16th||65.8||53.6||average||123%|
|Luncheon Hill (Forestry)||16.2||+0.7||21.4||6th||8.7||+0.7||5.2||25th||73.8||103.7||low||71%|
|Scottsdale (West Minstone Road)||17.2||-0.8||21.2||9th||7.6||-0.4||3.6||21st||100.0||81.7||high||122%|
|Sheffield School Farm||16.3||-0.2||19.8||5th||7.3||+0.3||4.3||16th||51.2||64.1||low||80%|
|East Coast (district 92)|
|Bicheno (Council Depot)||18.1||-0.8||21.1||5th||10.6||+0.3||7.4||25th||151.4||60.2||v high||251%|
|Eddystone Point||19.1||+1.0||22.3||8th||11.5||0.0||7.9||2nd||268.0||66.6||v high||402%|
|Fingal (Legge Street)||17.9||-0.4||23.4||9th||6.1||+0.6||0.9||8th||67.0||52.0||high||129%|
|Lake Leake (Elizabeth River)||14.3||+0.2||20.1||9th||5.1||+1.0||1.2||29th||61.2||69.8||average||88%|
|Maria Island (Point Lesueur)||16.8||21.4||8th||11.4||8.9||25th||93.0|
|Orford (Aubin Court)||17.4||-1.0||25.0||8th||7.5||-0.9||2.2||21st||72.0||58.2||high||124%|
|St Helens Aerodrome||18.1||-0.3||21.9||9th||9.7||+0.1||5.8||2nd||223.2||63.2||v high||353%|
|Swansea (Maria Street)||17.7||24.0||9th||3.8||29th||91.1|
|Midlands (district 93)|
|Ross (The Boulevards)||17.3||-0.2||23.1||9th||6.3||+0.7||0.7||16th||41.2||38.1||average||108%|
|Southeast (district 94)|
|Bull Bay (Lauriston)||17.1||-0.1||24.0||8th||9.7||+0.2||6.0||16th||108.0||48.6||v high||222%|
|Campania (Kincora)||18.4||-0.5||25.1||8th||8.4||+1.2||2.5||16th||95.2||39.2||v high||243%|
|Cape Bruny (Cape Bruny)||16.4||+0.1||23.7||8th||10.1||+0.3||6.6||25th||74.0||52.9||high||140%|
|Cape Bruny Lighthouse||15.9||+0.4||23.0||8th||10.1||+0.5||7.1||16th||76.6||79.9||average||96%|
|Geeveston (Cemetery Road)||17.4||+0.2||25.6||8th||7.3||+1.1||0.5||25th||105.4||64.2||high||164%|
|Grove (Research Station)||17.6||24.9||8th||6.5||-0.1||25th||79.4|
|Hobart (Ellerslie Road)||18.1||+0.8||25.6||8th||10.0||+1.1||5.0||16th||125.2||51.6||v high||243%|
|Hobart Airport||18.0||-0.1||25.1||8th||9.8||+1.1||5.4||16th||86.0||43.5||v high||198%|
|Maatsuyker Island Lighthouse||14.6||+0.1||22.4||8th||10.2||+0.7||6.5||22nd||104.4||108.2||average||96%|
|Melton Mowbray (North Stockman)||17.0||-0.3||23.5||7th||6.4||+0.7||0.2||16th||61.4||30.6||v high||201%|
|Mount Wellington||9.3||+1.0||15.9||7th||3.3||+1.2||-1.1||2nd||235.0||88.8||v high||265%|
|Tunnack Fire Station||15.1||-0.1||20.0||7th||6.0||+0.9||-0.4||16th||108.2||46.4||v high||233%|
|Derwent Valley (district 95)|
|Bushy Park (Bushy Park Estates)||18.9||+1.0||26.5||8th||6.2||0.0||0.9||25th||29.8||46.5||low||64%|
|Maydena Post Office||16.5||+0.7||24.3||8th||5.8||+0.4||2.0||25th||50.4||82.9||low||61%|
|Ouse Fire Station||18.2||-0.1||25.3||8th||5.8||+1.1||0.3||16th||27.6||30.7||average||90%|
|Central Plateau (district 96)|
|Lake St Clair National Park||13.5||+0.5||19.9||7th||3.5||+0.8||-1.3||16th||100.2||135.0||low||74%|
|West Coast (district 97)|
|Hartz Mountain (Keoghs Pimple)||11.6||+0.7||20.4||8th||5.5||+1.2||1.3||25th||136.2||69.4||v high||196%|
|Scotts Peak Dam||15.4||+0.9||24.2||8th||7.2||+0.6||2.7||25th||118.4||125.4||average||94%|
|King Island (district 98)|
|King Island Airport||17.8||+0.2||22.7||8th||11.1||+0.7||5.2||16th||42.2||56.8||low||74%|
|Flinders Island (district 99)|
|Flinders Island Airport||18.3||-0.4||23.5||9th||9.9||-0.8||5.2||11th||66.8||59.4||average||112%|
|Antarctica and Macquarie Island (district 300)|
|Macquarie Island||6.9||0.0||9.1||28th||3.4||-0.3||0.2||11th||61.0||93.1||v low||66%|
A Monthly Climate Summary is prepared to list the main features of the weather in Tasmania 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 9 am on Monday 2 May 2011. 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
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.