Tuesday, 5 January 2010 - Annual Climate Summary for Northern Territory - Product code IDCKGC12R0

Northern Territory in 2009

Details Extremes Records Summaries Important notes the top

Summary

Data collected by the Bureau of Meteorology indicate that the Northern Territory’s annual mean temperature for 2009 was 0.6 °C above the 1961-90 average, making it the Territory’s 11th warmest year since high quality records began in 1910. High temperatures were most notable in the south of the Territory during the second half of the year, with the NT recording its warmest July to December period on record.

Based on preliminary data, the overall Northern Territory mean rainfall for 2009 was 506.6 mm, about 33.5 mm less than the long-term average of 540.1 mm. Rainfall was very much below average in the south of the Territory in 2009, with several stations recording their lowest annual rainfall on record. An early end to the 2008-09 wet season and a late start to the 2009-10 wet season also resulted in below to very much below average rainfall across much of the central and western Top End. In contrast, above average annual rainfall was recorded across the Barkly district and the base of the Top End, with widespread flooding occurring in these regions in January and February during the monsoon.

Record breaking heatwaves and high temperatures

Record heat was widespread across the Territory from mid year with numerous high temperature records broken. August 2009 was the Territory’s and Australia’s warmest August on record, and saw the largest mean temperature anomaly ever recorded for the Territory for any month. The month saw abnormal heat over large parts of central Australia. Daytime temperatures were 4.0 to 6.0 °C above normal in the south of the Territory with 39% of the Territory recording record high maximum temperatures. August 2009 saw Alice Springs set a new high daily maximum temperature record on three separate occasions.

Maximum temperatures were unusually warm in Darwin during October 2009, with Darwin recording its highest monthly maximum temperature on record for any month. The average maximum temperature for the month was 34.8 °C at Darwin Airport, which is 1.6 °C higher than the long-term mean. On 10 December Darwin Airport equaled its all time warmest overnight temperature record dropping to only 29.7°C.

Another prolonged heat-wave affected central Australia during November 2009, leading to a November record of 15 consecutive days above 35.0 °C in Alice Springs.

Rainfall

The highest annual rainfall recorded in the Territory in 2009 was 2055.6 mm at Channel Island. The second and third highest annual totals were 2039.2 mm recorded at Lake Evella and 1932.2 mm recorded at Pirlangimpi AWS. In contrast, several locations in the Alice Springs district recorded their lowest annual rainfall on record this year, including Alice Springs Airport, Jervois and Papunya.

The highest daily rainfall recorded in the Territory in 2009 was 290.2 mm at Channel Island on 13 December; this was an all-time record for Channel Island. Several other sites also exceeded their all-time record highest daily rainfall on the 13th including 285.0 mm at Darwin River Dam (second-highest daily rainfall recorded in the Territory in 2009) and 280.0 mm at Walker Creek (third-highest daily rainfall recorded in the Territory in 2009). This widespread heavy rainfall was produced from a developing tropical depression as it moved south-westwards from the Arafura Sea, through the Van Diemen Gulf and over Darwin into the Timor Sea; the low later developed into Severe Tropical Cyclone Laurence.

Highest total rainfall, highest daily rainfall and lowest total rainfall records were established at several sites.

Maximum temperature

The hottest daytime maximum temperature recorded in the Territory in 2009 was 46.0 °C at Rabbit Flat on 8 December. The next day was also very hot for central and southern parts of the Territory with the second and third hottest daytime temperature of the year recorded on 9 December; 45.8 °C at Jervois and 45.6 °C at Rabbit Flat. Lajamanu recorded a maximum temperature of 45.4 °C on the 8th, an all-time daytime maximum temperature record for this site. The highest average of daytime maximum temperatures in 2009 was 35.8 °C, recorded at both Bradshaw AWS and Timber Creek. The second highest average maximum temperature was 35.5 °C at Kidman Springs, followed by 35.4 °C at Victoria River Downs.

The coldest daytime maximum temperature recorded in the Territory in 2009 was 9.0 °C at Kulgera on 30 May. The second coldest maximum was 9.6 °C at Alice Springs Airport on 30 May and the third coldest 10.1 °C recorded at both Arltunga on 30 May and Kulgera on 1 June. The coolest average of daytime maximum temperatures was 30.0°C at Alice Springs Airport. The second coolest average was 30.6 °C at Yulara Aero AWS and the third 30.8 °C at Gove Airport and Curtin Springs.

Highest temperature, coldest (lowest maximum temperature) and highest mean daily maximum temperature records were established at several sites.

Minimum temperature

Arltunga recorded the three coldest overnight minimum temperatures in the Territory during 2009 with observations of −1.7 °C, −1.5 °C and −1.3 °C (recorded on 5 August, 16 July and 6 August, and 4 August respectively). The lowest average of overnight minimum temperatures in 2009 was 14.3 °C recorded at Alice Springs Airport. The second lowest was 14.6 °C recorded at Curtin Springs and the third lowest 14.8 °C recorded at Yulara Aero AWS. It was the first year since 1973 in which the temperature at Alice Springs Airport has failed to fall below 0 °C, while the Territory annual low of −1.7 °C was the highest since a value of −1.0 °C, also in 1973.

The warmest overnight minimum temperature recorded in the Territory in 2009 was 32.2 °C at Rabbit Flat on 9 December and Jervois on 24 December. The second warmest overnight minimum was 31.8 °C recorded at Lajamanu on 22 November, followed by, 31.5 °C at Yulara Aerodrome AWS on 25 January. The warmest average of overnight minimum temperatures was 25.2 °C at Cape Don AWS. The second warmest was 24.6 °C recorded at Warruwi AWS and the third warmest was 24.2 °C recorded at Black Point

Warmest night (highest daily minimum temperature), highest mean daily minimum temperature and lowest mean daily minimum temperature records were established at several sites.

Further information

NT Climate Services Centre
Bureau of Meteorology
Phone (08) 8920 3813
Email climate.nt@bom.gov.au
Extremes in 2009
Hottest day 46.0 °C at Rabbit Flat on 8 Dec
Warmest days on average 35.8 °C at Bradshaw
35.8 °C at Timber Creek
Coolest days on average 30.0 °C at Alice Springs Airport
Coldest day 9.0 °C at Kulgera on 30 May
Coldest night -1.7 °C at Arltunga on 5 Aug
Coolest nights on average 14.3 °C at Alice Springs Airport
Warmest nights on average 25.2 °C at Cape Don AWS
Warmest night

32.2 °C at Rabbit Flat on 9 Dec
32.2 °C at Jervois on 24 Dec
Wettest overall 2055.6 mm at Channel Island
Wettest day 290.2 mm at Channel Island on 13 Dec
Highest wind gust 120 km/h at Borroloola on 13 Nov

Details Extremes Records Summaries Important notes the top

Record highest annual daily rainfall
Highest daily rainfall (mm) Previous highest Years of
record
Daly Waters AWS 156.8 on 30 Jan 147.1 on 15 Mar 1944 34
Darwin River Dam 285.0 on 13 Dec 208.4 on 10 Dec 1998 34
Channel Island 290.2 on 13 Dec 249.6 on 3 Jan 1997 24
Stokes Hill 273.6 on 13 Dec 246.6 on 16 Mar 1977 12
Walker Creek 280.0 on 13 Dec 255.2 on 3 Mar 2007 10


Record lowest total annual rainfall
Total rainfall
for 2009 (mm)		 Previous annual
lowest		 Years of
record		 Annual
average
Alice Springs Airport 76.8 82.1 in 1965 67 279.4
Jervois 97.8 106.8 in 2003 41 282.7
Yambah 85.8 97.7 in 1994 35 311.6
Allambi 35.0 60.7 in 1994 34 253.9
Ross River 93.6 141.0 in 1996 22 374.2
Wallace Rock Hole 87.6 97.4 in 1996 21 265.9
Trephina Gorge 90.7 127.2 in 1996 16 309.0


Record highest annual temperature
Highest daily temperature (°C) Previous highest Years of
record		 Annual
average
Lajamanu AWS 45.4 on 8 Dec 45.0 on 5 Dec 2004 11 33.6
Black Point 36.1 on 19 Oct = 36.1 on 22 Oct 2008 13 31.3
Dum In Mirrie AWS 38.0 on 18 Oct 37.7 on 23 Oct 2008 10 31.6


Record lowest annual daily maximum temperature
Lowest daily maximum
temperature (°C)		 Previous lowest Years of
record		 Average
Kulgera 9.0 on 30 May = 9.0 on 23 Jul 1998 21 28.1


Record highest annual mean daily maximum temperature
Mean daily maximum
temperature (°C)		 Previous highest Years of
record		 Average
Timber Creek 35.8 35.6 in 1992 27 34.8
Pirlangimpi 32.9 32.6 in 2008 19 32.1
Jabiru Airport 35.3 35.1 in 2005 22 34.3
Tindal RAAF 34.6 34.6 in 1986 16 33.7


Record highest annual daily minimum temperature
Highest daily minimum
temperature (°C)		 Previous annual
highest		 Years of
record		 Annual
average
Darwin Airport 29.7 on 10 Dec = 29.7 on 3 Dec 2007 64 23.2
Lajamanu 31.8 on 22 Nov 30.1 on 2 Dec 2007 10 17.9
Black Point 30.2 on 9 Dec 30.0 on 26 Nov 1998 12 24.0
Rabbit Flat 32.2 on 9 Dec 31.2 on 30 Nov 1996 10 16.6


Record highest annual mean daily minimum temperature
Mean daily minimum
temperature (°C)		 Previous annual
highest		 Years of
record		 Annual
average
Pirlangimpi AWS 22.8 = 22.8 in 2007 23 22.1


Details Extremes Records Summaries Important notes the top

Summary statistics for 2009
Maximum temperatures
(°C)		 Minimum temperatures
(°C)		 Rainfall
(mm)
Mean Diff
from
average		 Highest Mean Diff
from
average		 Lowest Total Average
annual
total		 Rank Fraction
of annual
average
Darwin-Daly (district 14GA)
Batchelor Aero AWS 34.2   39.2 3 Oct 21.3   7.4 20 Jun 1423.8 1606.8 average 89%
Black Point 31.8 +0.5 36.1 19 Oct 24.2 +0.2 15.5 20 Jun 845.9 1273.2 v low 66%
Bradshaw AWS 35.8   44.0 5 Dec 21.9   8.0 12 Jun 1476.4
Cape Don AWS 31.4   35.8 6 Dec 25.2   20.0 17 Jul 897.0 1279.3 low 70%
Central Arnhem Plateau AWS 32.7   39.4 15 Nov 20.4   8.9 19 Jun 1045.4
Darwin Airport 32.7 +0.7 38.0 18 Oct 23.4 +0.2 14.9 20 Jun 1736.8 1707.4 average 102%
Jabiru Airport AWS 35.3 +1.1 41.2 18 Nov 22.9 +0.4 13.0 20 Jun 1056.2 1549.1 v low 68%
Katherine Aviation Museum 34.5 +0.4 41.5 9 Dec 20.1 -0.2 6.0 20 Jun 1066.8 1128.4 average 95%
Mango Farm 34.8 +0.7 41.0 3 Oct 20.2 -0.3 5.9 20 Jun 1351.1 1398.7 average 97%
Noonamah AWS 34.8   40.8 17 Oct 21.5   8.4 20 Jun 1808.6
Pine Creek Council 34.2   39.7 18 Nov 21.8   10.6 17 Jul 1431.5
Pirlangimpi AWS 32.9 +0.8 36.8 18 Oct 22.8 +0.7 14.6 9 Jul 1932.2 2007.9 average 96%
Tindal RAAF AWS 34.6 +0.9 41.1 15 Nov 20.7 +0.2 6.8 20 Jun 822.6 1135.4 low 72%
Arnhem (district 14BC)
Gove Airport 30.8 +0.2 36.1 2 Dec 22.1 -0.3 14.3 22 May 1368.6 1432.1 average 96%
Maningrida Aero AWS 32.3   37.3 18 Oct 22.4   14.0 11 Jun 862.2
Ngayawili AWS 31.6   36.5 16 Oct 22.7   15.3 16 Jul 1460.8
Warruwi AWS 31.5 +0.3 36.4 3 Dec 24.6 +0.3 18.1 20 Jun 816.6 1151.3 low 71%
Roper-Mcarthur (district 14DE)
Borroloola AWS 34.3 +0.6 40.7 2 Dec 19.2 -0.5 5.9 18 Jul 348.4 892.7 v low 39%
Larrimah 34.3 +0.4 41.5 8 Dec 18.8 -0.9 5.0 20 Jun 1051.8 839.4 high 125%
McArthur River Mine 35.0 +0.5 41.9 6 Dec 20.1 +0.6 5.7 17 Jul 883.2 711.4 high 124%
Wollogorang 33.9 +0.2 41.5 7 Dec 18.2 -0.7 3.0 17 Jul 1025.7 919.0 average 112%
Victoria (district 14F)
Kidman Springs 35.5 +0.6 43.5 7 Dec     4.8 17 Jul 1025.7 737.4 v high 139%
Timber Creek 35.8 +0.9 43.5 7 Dec 20.4 -0.8 5.7 21 Jun 837.0 941.9 low 89%
Victoria River Downs 35.4 +1.0 43.4 8 Dec 19.1 -0.5 3.6 19 Jun 828.5 642.9 high 129%
Wave Hill 34.8 +0.6 44.6 7 Dec 18.8 0.0 3.0 19 Jun 784.1 689.5 high 114%
Barkly (district 15A)
Elliott 34.4 -0.2 43.5 9 Dec 18.8 -0.3 5.5 20 Jun 776.0 592.4 high 131%
Tennant Creek Airport 32.4 +0.5 43.0 8 Dec 20.0 +0.2 8.0 18 Jun 457.6 454.2 average 101%
Alice Springs (district 15B)
Alice Springs Airport 30.0 +1.3 43.2 8 Dec 14.3 +1.1 0.2 17 Jul 77.0 279.4 lowest 28%
Curtin Springs 30.8 +1.2 44.0 7 Dec 14.6 +1.2 -0.9 16 Jul 72.0 235.4 v low 31%
Jervois 31.5 +0.5 45.8 9 Dec 16.1 +1.6 1.0 17 Jul 89.4 282.7 lowest 32%
Rabbit Flat 34.8 +1.1 46.0 8 Dec 16.9 +0.3 0.5 16 Jul 263.2 495.0 low 53%
Territory Grape Farm AWS 31.4 +0.5 43.5 8 Dec 15.2 +0.6 1.7 16 Jul 138.4 309.7 v low 45%
Watarrka 30.9 +0.3 43.4 17 Nov     -1.0 14 Jul 116.6 311.7 low 37%
Yuendumu 32.0 +1.6 43.0 8 Dec 16.1 +0.7 1.4 20 Jun 202.9 370.4 low 55%
Yulara Aero 30.6 +0.6 44.2 6 Feb 14.8 +0.8 -0.9 17 Jul 175.2 275.4 average 64%

Details Extremes Records Summaries Important notes the top

Notes

A Annual Climate Summary is prepared to list the main features of the weather in Northern Territory 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 10 am on Monday 21 December 2009. 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 the years 1800 to 2008. They are not shown for sites with less than 10 years of record in that time, 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

NT Climate Services Centre
Bureau of Meteorology
Phone (08) 8920 3813
Email climate.nt@bom.gov.au