Tuesday, 1 March 2011 - Monthly Climate Summary for Northern Territory - Product code IDCKGC22R0
Late in the day on 13 February a tropical low pressure system developed over Australia’s Top End, centred about 50 km north of Katherine. As this system moved to the northwest, exceptionally wet conditions began to develop over Darwin and rural areas, becoming notably intense late on the 15th. It was about this same time that the system emerged over Darwin Harbour. Conditions were ripe for the tropical low to intensify as it moved over the warm ocean waters. The low pressure system became Tropical Cyclone Carlos, of category 1 intensity, while over Darwin Harbour on the 16th. The cyclone remained slow moving over the city of Darwin for over 24 hours. By early on the 17th, the system had moved southeast of Darwin and was downgraded to a tropical low. Due primarily to the slow movement of the storm, several rainfall records were broken during this three day period.
Heavy rain from the slow moving TC Carlos added to the already wet conditions and produced an exceptionally wet February. Darwin Airport recorded 367.6 mm of rain in the 24 hour period to 9 am on 16 February. The previous wettest day for Darwin Airport was recorded on 3 January 1997 when Tropical Cyclone Rachel brought 290.4 mm of rain. The Darwin Airport 3-day total (15 to 17 February) was 684.8 mm, breaking the previous 3-day record established between 8th December 1998 and 10th December 1998 when Severe Tropical Cyclone Thelma brought 462.0 mm of rain. In the 7-days period from the 13th to 19th Darwin Airport measured 847.4mm. The previous record for the wettest week at Darwin Airport was 615.8mm set in 6 to 12 January 1991. Moreover, Darwin Airport accumulated 1110.2 mm of rain, breaking the previous monthly record of 1013.6 mm set in March of 1977.
As pre-TC Carlos approached Darwin, the maximum temperature for the 15th at Darwin Airport reached only 24.8° C. The previous record low February maximum temperature was 25.6° C set on the 3rd in 1956.
On the 22nd, a thunderstorm at Jabiru dumped a total of 190 mm of rain in a day, including 70.2 mm in 34 minutes and 119.8 mm in 94 minutes.
On the 16th, again due to pre-TC Carlos, nearly all recording stations around the Greater Darwin region measured their highest 24 hour rainfall on record: Leanyer* recorded the highest with 344.2 mm at which point the rain gauge over flowed, Darwin Airport recorded 367.6 mm, Channel Island had 311.2 mm and Palmerston had 300.0 mm which were all daily rainfall records. New 3-day rainfall records were also set with Channel Island receiving the highest 3-day rainfall accumulation with 808.1 mm in the 3-day period from the 15th to the 17th. During the same 3-day period, Fort Hill Wharf recorded 781 mm and 684.8 mm fell at Darwin Airport. On the 18th, as ex-TC Carlos moved to the south west, more rainfall records were broken when 230.2 mm fell at Mango Farm.
The wettest overall was Leanyer* with 1179.6 mm which is an underestimate because the rain guage overflowed on the 16th. The next wettest was at Channel Island with 1147.8 mm followed by Darwin Airport with 1110.2 mm; this marks the highest total February rainfall on record at each of these sites.
The driest overall was at Alexandria with 1.4 mm.
The wettest single day was on the 16th at Darwin Airport with 367.6 mm, followed by Geriatric Park with 363.2 mm on the 15th and then Leanyer* with 344.2 on the 16th.Tropical cyclone Carlos brought the highest February daily rainfall on record to most sites in the Darwin-Daly rainfall district.
The mean maximum temperatures for the month remained cooler than normal throughout the Territory. The mean minimum temperatures were cooler in the northern half and warmer in the south. The average mean maximum temperature in the Territory for the February was 33.16°C and the Territory average minimum temperature was 23.03°C.
A persistent monsoon trough, along with the rainy weather over the northern half of the Northern Territory during the month contributed to the below normal maximum temperatures in the region. Average maximum temperatures were 3 to 4 degrees below normal in central parts of the Territory.
The warmest days on average were at Walungurru with 37.4 °C, followed by Yulara 35.6°C.
The hottest day was on the 4th in far southern NT when Walungurru reached 42.0 °C , followed by Curtin Springs with 41.0 °C and Yulara Aero measured 40.0 °C, all on the same day.
The coolest days on average were at Central Arnhem Plateau with 29.8 °C, followed by Black Point with 30.1 °C and then Channel Point with 30.4 °C.
The coldest day was at Watarrka with 22.4 °C and Yulara Aero with 22.8 °C on the 6th when ex-TC Yasi brought thick cloud and rain to the far southern NT. The next coldest day was at Batchelor Aero with 23.9 °C on the 16th.
Some sites, including Darwin Airport, had their coldest February day (lowest maximum temperature) on record. Two sites had their lowest February mean daily maximum temperature on record, these were Channel Point and Delamere Weapons Range.
Minimum temperatures over the northern half of the Territory remained cooler than normal where as in the southern parts they remained warmer than normal.
The coldest night was at Kulgera with 14.5 °C on the 23rd, followed by Arltunga with 14.9 °C on the 26th.
The coolest nights on average were at Arltunga with 20.7 °C, followed by Kulgera with 21.3 °C.
The warmest nights on average were at Centre Island with 25.6 °C, followed by Dum In Mirrie with 25.2 °C.
The warmest night was at Centre Island with 29.1 °C on the 4th, followed by Dum In Mirrie with 29.0 °C also on the 4th.Some sites had their lowest February mean daily minimum temperature on record.
This months highest wind gusts were all associated with TC Carlos. The strongest wind gust was at was at Darwin Airport with 98 km/h on the 15th, followed by Point Fawcett with 91 km/h on the 16th, and then Darwin Airport with 83 km/h on the 16th.
Flooding occured in the Daly and Adelaide Rivers as a result of the heavy rainfall from TC Carlos.
|Extremes in February 2011|
42.0 °C at Walungurru on the 4th
|Warmest days on average||
37.4 °C at Walungurru
|Coolest days on average||
29.8 °C at Central Arnhem Plateau
22.4 °C at Watarrka on the 6th
14.5 °C at Kulgera on the 23rd
|Coolest nights on average||
20.7 °C at Arltunga
|Warmest nights on average|| 26.2 °C at North East Island
|Warmest night|| 29.1 °C at Centre Island on the 4th
|Warmest on average overall||
30.7 °C at Walungurru
|Coolest on average overall||
26.1 °C at Central Arnhem Plateau
1179.6 mm at Leanyer*
|Driest overall||1.4 mm at Alexandria|
|Wettest day||442.5 mm at Daly River Police Station on the 18th|
|Highest wind gust||98 km/h at Darwin Airport on the 15th|
|Record highest February daily rainfall|
|Highest daily rainfall (mm)||
|Darwin Airport||339.6||on the 16th||250.2||on the 18th in 1955||70|
|Tipperary||222.8||on the 18th||177.8||on the 5th in 1942||41|
|Darwin River Dam||216.0||on the 15th||115.0||on the 14th in 1975||39|
|Larrakeyah||234.6||on the 17th||210.5||on the 20th in 2008||35|
|Channel Island||311.2||on the 16th||158.8||on the 16th in 1938||34|
|Jabiru Airport||190.4||on the 22nd||155.8||on the 5th in 1980||18|
|McMinns Lagoon||205.0||on the 16th||135.4||on the 23rd in 1997||34|
|Atula||119.6||on the 22nd||119.2||on the 28th in 2010||32|
|Humpty Doo Collard Road||214.2||on the 15th||144.4||on the 23rd in 1997||30|
|Mango Farm||230.2||on the 18th||123.0||on the 11th in 1981||28|
|Elizabeth Valley||158.7||on the 16th||121.4||on the 17th in 2003||22|
|Karama*||191.7||on the 17th||190.8||on the 22nd in 1997||23|
|Stokes Hill||288.4||on the 16th||148.3||on the 6th in 1969||18|
|Leanyer*||344.2||on the 16th||179.2||on the 20th in 2008||20|
|Territory Wildlife Park||173.0||on the 15th||108.2||on the 18th in 2009||18|
|Shoal Bay||284.2||on the 16th||210.4||on the 22nd in 1997||15|
|CSIRO Berrimah||192.4||on the 17th||181.0||on the 20th in 2008||18|
|Record highest total February rainfall|
|Total rainfall (mm)||
|Darwin Airport||1068.0||814.5||in 1969||70||364.6|
|Darwin River Dam||829.2||599.0||in 1984||39||324.8|
|Channel Island||1147.8||756.5||in 2003||35||342.6|
|McMinns Lagoon||862.9||855.4||in 2003||34||371.6|
|Humpty Doo Collard Road||836.7||724.2||in 2003||30||348.3|
|Stokes Hill||912.8||668.0||in 1969||18||306.4|
|Elizabeth Valley||883.1||762.0||in 2003||21||348.4|
|CSIRO Berrimah||800.2||769.4||in 2003||17||431.7|
|Shoal Bay||973.1||666.0||in 2008||15||419.1|
|Record lowest February daily maximum temperature|
Lowest daily maximum
|Darwin Airport||24.8||on the 15th||25.6||on the 3rd in 1956||68||31.4|
|Mango Farm||25.0||on the 17th||25.5||on the 16th in 2003||28||33.1|
|Batchelor Aero||23.9||on the 16th||25.2||on the 3rd in 2004||15||32.2|
|Dum In Mirrie||26.1||on the 15th||26.7||on the 19th in 2008||12||31.0|
|Record lowest February mean daily maximum temperature|
Mean daily maximum
|Channel Point||30.4||30.5||in 2008||16||31.5|
|Delamere Weapons Range||31.9||32.1||in 2004||12||34.2|
|Record lowest February mean daily minimum temperature|
Mean daily minimum
|Black Point||24.8||24.9||in 1994||19||25.6|
|Batchelor Aero||23.4||23.6||in 2006||15||23.8|
|Point Fawcett||24.7||24.9||in 2003||11||25.6|
|Groote Eylandt Airport||24.4||24.6||in 2007||11||25.0|
|Pine Creek Council||23.3||23.4||in 2002||10||23.8|
|Summary statistics for February 2011|
|Darwin-Daly (district 14GA)|
|Batchelor Aero||30.8||-1.4||34.5||3rd||23.4||-0.4||21.6||14th||608.0||367.7||v high||165%|
|Black Point||30.1||-0.9||32.4||22nd||24.8||-0.8||21.9||15th||520.2||282.6||v high||184%|
|Central Arnhem Plateau||29.8||34.4||1st||22.4||20.8||12th||418.6|
|Delamere Weapons Range||31.9||-2.3||35.6||3rd||23.5||-0.4||21.4||22nd||358.4||234.4||high||153%|
|Dum In Mirrie||30.7||-0.3||32.9||5th||25.2||0.0||23.2||15th||663.4||459.3||high||144%|
|Jabiru Airport||31.9||-1.2||36.2||3rd||24.2||-0.2||22.3||16th||726.0||364.7||v high||199%|
|Katherine Aviation Museum||32.2||-1.8||35.7||3rd||23.7||-0.2||22.3||9th||359.6||244.9||high||147%|
|Pine Creek Council||31.3||-1.2||34.6||1st||23.3||-0.5||21.7||16th||473.0|
|Port Keats Aero||31.4||34.0||3rd||24.4||22.4||1st||424.2|
|Arnhem (district 14BC)|
|Groote Eylandt Airport||31.9||-0.7||35.5||3rd||24.4||-0.6||21.7||9th||287.8||272.4||average||106%|
|North East Island||32.0||33.6||4th||26.2||23.3||9th||233.0||169.3||high||138%|
|Roper-Mcarthur (district 14DE)|
|Centre Island||31.7||-1.2||36.2||3rd||25.6||-1.0||23.0||13th||548.6||268.8||v high||204%|
|McArthur River Mine||33.5||-1.7||38.7||3rd||24.2||-0.5||22.7||16th||265.2||184.5||high||144%|
|Victoria (district 14F)|
|Victoria River Downs||33.1||-2.3||37.1||3rd||24.1||-0.4||21.7||22nd||175.8||162.0||average||109%|
|Barkly (district 15A)|
|Tennant Creek Airport||33.2||-2.5||36.1||2nd||22.9||-1.6||20.9||1st||298.2||118.6||high||251%|
|Alice Springs (district 15B)|
|Alice Springs Airport||33.4||-1.7||36.2||19th||21.5||+0.7||16.7||23rd||111.2||41.3||high||269%|
|Territory Grape Farm||34.5||-1.8||36.6||20th||21.7||0.0||18.9||23rd||79.2||70.2||high||113%|
|Yulara Aero||35.6||-1.3||40.0||4th||23.0||+0.8||16.6||7th||86.0||39.4||v high||218%|
|Offshore Islands (district 200)|
* Rain guage overflowed at Leanyer and Karama on the 16th.
A Monthly 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 28 February 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
the years 1800 to 2009.
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
(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.