Climate of Launceston, Tasmania explained

See main article: Climate of Tasmania and Climate of Australia. Launceston, Tasmania has a cool, temperate climate,[1] with four distinct seasons. The city is located in the Tamar Valley in Northern Tasmania and is surrounded by many large hills and mountains. With this type of topography, Launceston's weather patterns can change considerably in a short period.[2]

Background

The warmest months are in January and February with an average air temperature range of 12.20NaN0 up to 34.40NaN0. Throughout the year there is an average of 4.3 days a year over 300NaN0. The maximum recorded temperature was 390NaN0 on 30 January 2009, with Launceston Airport reaching 40.40NaN0 on that same day, during the 2009 Southeastern Australia heat wave. Having 2,500 hours of annual sunshine, Launceston is sunnier than Melbourne, a northward city in mainland Australia, which only receives around 2,300 hours of annual sunshine.

Winters are cool with minimum temperatures dropping below 20NaN0 an average of 61 days a year. The coldest month is July, with an average temperature range of 2.20NaN0 - 12.50NaN0.The lowest recorded minimum at Launceston's current weather station, Ti Tree Bend was -5.2C. Unlike many other areas of Tasmania and as well as a number of cities in the northern hemisphere that lie on the same latitude (such as Chicago, Cleveland, Tashkent, Tbilisi and Shenyang), Launceston rarely receives snowfall and is relatively mild.[3] [4]

Winter, for Launceston, is also the season with the least amount of wind. Because of this and the topographical effect of the Tamar Valley, Launceston winters are renowned for foggy mornings, with Launceston Airport the most fog-bound commercial airport in Australia. The average annual rainfall, with moderate to low variability is 6650NaN0, with 1mm falling an average of 88.4 days a year. The most rain Ti Tree Bend has received in a year was in 1992, though Launceston Airport received 953.1mm during 1956. As in most of Tasmania, 2006 was the driest year when just fell.[5] [6]

Precipitation

There is an average of of rain a year (at the airport). Cold fronts in winter account for much of this precipitation, with mountains surrounding Launceston regularly receiving snow in autumn, winter and spring.[7] Launceston annual rainfall is somewhat lower than that of surrounding areas, particularly further north in the Tamar valley. This is due to the rain shadow effect of the Western Tiers located West of the city.

Rainfall elements
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Yearly
Highest monthly rainfall139.4 107.4 106.2 124.6 152.9 183.0 157.7 183.6 115.8121.4 85.2 145.1 829.6
Lowest monthly rainfall9.8 0.0 2.6 4.3 4.0 4.3 36.8 14.9 8.4 9.9 5.6 6.1 394.8
Source: Climate statistics for Launceston (Ti Tree Bend), Bureau of Meteorology

Seasonal conditions

Launceston has a cool, temperate climate,[1] with four distinct seasons. Surrounded by many large hills and mountains, Launceston's weather patterns can change considerably in a short period.The warmest months are in January and February with an average air temperature range of 12.20NaN0 to 24.40NaN0. Throughout the year there is an average of 4.3 days a year over 300NaN0. The maximum recorded temperature was 390NaN0 on 30 January 2009, with Launceston Airport reaching 40.40NaN0 on that same day, during the 2009 Southeastern Australia heat wave.Winters are cool with minimum temperatures dropping below 20NaN0 an average of 61 days a year. The coldest month is July, with an average temperature range of 2.20NaN0 to 12.50NaN0.The lowest recorded minimum at Launceston's current weather station, Ti Tree Bend, was -5.2C, and unlike many other areas of Tasmania, Launceston rarely receives snowfall.

The average annual rainfall, with moderate to low variability, is 6650NaN0, falling on an average of 88.4 days a year. The most rain Launceston received in a year was in 2016, with 2006 being the driest year when just fell.[5] [6]

The Bureau of Meteorology reported that 2007 was the hottest year ever recorded in Launceston since temperatures were first recorded in 1884. Temperatures ranged from a minimum of 8.1C to a maximum of 19.2C.[8] During 2006 and 2007, Launceston had the hottest maximums throughout the state. In 2008, Launceston had the highest average maximum temperature out of all Tasmanian cities with 18.6C.[3] [4] [7] [9]

Summer

During the summer, city minimums range from 90NaN0 in December, and up to 10.30NaN0 in February. High temperatures during Summer range from 21.20NaN0 in December and 23.20NaN0 in the hottest month, February. Temperatures above 30C are extremely rare compared even to cities like Melbourne, occurring on fewer than five days per year as against thirty in Melbourne and over fifty in Adelaide. Launceston generally does not receive as many large thunderstorms as cities in mainland Australia, although during summer, thunderstorms are more frequent than in any other season. The Launceston suburb of Summerhill was hit by a tornado that descended from a thunderstorm on Christmas Eve 2001. Estimates suggest the tornado had wind speeds of between 200 and 250 km/h.There is an average of 4.5 days each summer of temperatures over 300NaN0 and during the 2009 South Eastern Australia heatwave, Ti Tree Bend surpassed its previous record temperature of 350NaN0 three days straight. Rainfall is at its lowest during Summer, with an average of and approximately 22 days of rain during the three months.

Summer Record
Record Date
Highest Summer Maximum Temperature39.90NaN0 30 January 2009
Lowest Summer Minimum Temperature-10NaN0 20 December 1977
Highest Summer Monthly RainfallFebruary 1969
Lowest Summer Monthly RainfallFebruary 1983
Source:

Autumn

Autumn is a season of transition, and generally has the most settled weather patterns, although Launceston's worst floods both occurred in Autumn. City minimums range from 5.10NaN0 in May, and up to 100NaN0 in March. High temperatures during Autumn range from 15.80NaN0 in May up to 22.40NaN0 in March.[7]

Autumn Record
Record Date
Highest Autumn Maximum Temperature34.90NaN0 4 March 1942
Lowest Autumn Minimum Temperature-4.80NaN0 23 May 2001
Highest Autumn Monthly RainfallMay 1958
Lowest Autumn Monthly RainfallMarch 1972
Source:

Winter

On average, wintertime lows dip down to 2.30NaN0 in July, while daytime highs range from 12.50NaN0 in July up to 13.70NaN0 in August. Winter is typically the season with the least amount of wind, although the increased occurrence of cold frontal systems during the cooler months have helped cause wind gusts of up to 113 km/h - in the winters of 1949 and 1984 at Launceston Airport, 14.8 km away from Ti Tree Bend. This passage of cold frontal systems are responsible for winter being Launceston's and the rest of northern and western Tasmania's wettest season.

Winter Record
Record Date
Highest Winter Maximum Temperature18.70NaN0 26 August 2004
Lowest Winter Minimum Temperature-7.10NaN0 24 June 1972
Highest Winter Monthly RainfallAugust 1936
Lowest Winter Monthly RainfallJune 2007
Source:

Spring

Spring is mostly a transition from winter to summer. Cold weather reaches Tasmania less often and temperatures slowly begin to rise. Snowfalls, although rare, have been recorded in Launceston's surrounding areas as late as October, during 1940, 1978, 2003 and 2020. The month of October experiences the greatest rise in temperatures.

Spring Record
Record Date
Highest Spring Maximum Temperature30.70NaN0 1 November 1987
Lowest Spring Minimum Temperature-2.40NaN0 7 September 1994
Highest Spring Monthly RainfallOctober 1947
Lowest Spring Monthly RainfallSeptember 1994
Source:

2009 Southeastern Australia heat wave

The 2009 southeastern Australia heat wave was a heat wave that commenced in late January and led to record-breaking prolonged high temperatures in the region.[10] During the heat wave, 50 separate locations across Australia set various records for consecutive, highest daytime and overnight temperatures.

The exceptional heat wave was caused by a slow moving high-pressure system that settled over the Tasman Sea, with a combination of an intense tropical low located off the North West Australian coast and a monsoon trough over Northern Australia, which produced ideal conditions for hot tropical air to be directed down over Southeastern Australia.[11] The heat began in South Australia on 25 January but became more widespread over southeast Australia by 27 January. A weak cool change moved over the southern coastal areas bringing some relief on 30 January;[11] in Melbourne the change arrived on the evening and dropped temperatures to an average of 30.8°C. Higher temperatures returned on the following weekend with Melbourne recording its hottest day since records began in 1855: 46.4°C, also the hottest temperature ever recorded in an Australian capital city.[12]

During the heat wave, several records were broken; Tasmania recorded its highest ever temperature; in Scamander, and the long-standing Tasmanian record of (recorded in Hobart on 4 January 1976) was broken five times within two days at Flinders Island, Fingal (twice), St Helens and Scamander. Launceston recorded its highest recorded temperature of 38.2°C on 31 January.[13] The heat wave generated extreme fire conditions during the peak of the 2008–09 Australian bushfire season, causing many bushfires in the affected region, contributing to the extreme bushfire conditions on 7 February, also known as the February 2009 Victorian bushfires, which claimed 173 lives in Victoria.[14]

Launceston in January 2009

39°C - Hottest day recorded in Launceston since records began in 1880.[16]

See also

Notes and References

  1. Web site: Supervising Scientist Report . Australian Government . Department of the Environment, Water, Heritage and the Arts . 4 . https://web.archive.org/web/20090318075816/http://www.environment.gov.au/ssd/publications/ssr/pubs/ssr128-chap2.pdf. 18 March 2009. 31 January 2009 .
  2. Web site: Geography of Launceston. https://web.archive.org/web/20080516230046/http://www.asiarooms.com/travel-guide/australia/launceston/launceston-overview/geography-of-launceston.html. usurped. 16 May 2008. Asia Rooms. 14 November 2008.
  3. Web site: Tasmania in 2007. Bureau of Meteorology. Australian Government. 28 July 2008.
  4. Web site: Tasmanian 2006. Bureau of Meteorology. Australian Government. 1 November 2008.
  5. Web site: Tasmania breaks all-time high temperature record again. Bureau of Meteorology. Australian Government. 30 January 2009. 31 January 2009.
  6. Web site: 42.2 deg: Scamander sets State's hottest record!. The Examiner. Fairfax Media. 31 January 2009. 31 January 2009.
  7. Web site: Climate of Launceston. Bureau of Meteorology. Australian Government. 2 September 2008.
  8. http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=36&p_display_type=dataFile&p_stn_num=091104 Mean Maximum Temperatures for Launceston Airport Comparison
  9. Web site: Climate of Launceston. Bureau of Meteorology. Australian Government. 26 July 2008. https://web.archive.org/web/20090222154659/http://www.bom.gov.au/weather/tas/launceston/climate.shtml. 22 February 2009. dead.
  10. News: Heatwave record set in Melbourne . Australian Broadcasting Corporation . ABC News . 30 January 2009 . 1 February 2009.
  11. Book: The exceptional January-February 2009 heatwave in south-eastern Australia . National Climate Centre . Bureau of Meteorology . 2 . 12 February 2009 .
  12. News: City swelters, records tumble in heat . The Age, Melbourne . 7 February 2009. 7 February 2009 . Hamish . Townsend.
  13. News: Houses destroyed, records broken in heatwave. 30 January 2009. The Australian. News Limited. 31 January 2009. https://web.archive.org/web/20090306064954/http://www.theaustralian.news.com.au/story/0,25197,24984926-12377,00.html. 6 March 2009. dead.
  14. Web site: Bushfire update . Victorian Government . Victoria Police . 9 February 2009 . 9 February 2009 . dead . https://web.archive.org/web/20090212125322/http://police.vic.gov.au/content.asp?Document_ID=19190 . 12 February 2009 .
  15. Web site: Launceston, Tasmania January 2009 Daily Weather Observations . Australian Government . Bureau of Meteorology . 4 February 2009 . dead . https://web.archive.org/web/20090205153252/http://www.bom.gov.au/climate/dwo/200901/html/IDCJDW7025.200901.shtml . 5 February 2009 .
  16. Web site: Tasmania in January 2009 . Australian Government . Bureau of Meteorology . 9 February 2009.