Wednesday, 1 May 2013 - Seasonal Climate Summary for Northern Territory - Product code IDCKGC22R0

Northern Territory in October to April 2012-13: Dry, humid and hot

• A late start to the North Australia Monsoon
• Hottest October to April (northern wet season) on record: Alice Springs and Darwin
• Gove Airport
• driest start of a wet season on record
• 300 mm below previous lowest by 1 March
• ended as second driest on record
• Easter weekend storm
• set several new daily rainfall records
• reduced rainfall deficit

Extremes Maps Records Summaries Important notes the top

October thunderstorm sets new Darwin daily rainfall record for northern suburbs

On the morning of Sunday 29 October, a slow moving trough crossed over the western Top End. The rainfall was a classic example of very localised heavy rainfall over Darwin as both the northern suburbs and the region from Humpty Doo to the Cox Peninsula received more than 40 mm while the Airport and the immediate suburbs to the south, including the city, missed out (The Airport recorded only 6 mm for the day). Leanyer managed to pick up 110.8 mm, their highest October daily total in 23 years worth of records.

Driest start of the wet season for Arnhem Land

Dry conditions dominated most of the Arnhem and the Roper - McArthur Districts in November and December. A persistent broad-scale area of very dry air which extended into the middle layers of the atmosphere for most of November and into December. This dry air prevented gulf lines from initiating convection over land. As gulf lines approached the Gove area from the east they would quickly dissipate before reaching the coast, leaving Gove and eastern Arnhem Land sorely dry. Gove Airport failed to register any rainfall during November, the second time in their record with 0.0 mm in November, the first being in 1994. By the end of November Gove Airport had only measured 7.8 mm of rain for the wet season, well under their October to November average of 55.6 mm. Farther south, Borroloola received 13.8 mm, their lowest November rainfall since 2006.

Following the dry November, December also saw low rainfall totals with a late monsoon onset. Gove Airport saw their second driest December on record with only 6.4 mm for the month, the long-term December average at Gove is 181.2 mm. Maningrida, Milingimbi, Ngayawili and Groote Eylandt Airport all had their driest October to December period on record.

Late onset of North Australian Monsoon

On average the North Australian Monsoon sets onto the Top End around the last week of December. This year, however, the monsoon did not arrive in December and rainfall totals for the month were lower than average for all of the Top End. Adelaide River Post Office, Pirlangimpi, Howard Springs Nature Park, and Darwin Hospital all saw their driest December on record. Leanyer, Karama, and Wagait Beach all saw their second driest December on record and it was mostly attributed to a lack of monsoon rainfall.

Beginning on 4 January, a monsoon trough formed off Australia's north coast, but it remained offshore due to a stationary high pressure area over the continent. Even as tropical cyclone Narelle moved south (off the WA northwest coast), from the 9th to the 14th, the high pressure over eastern Australia prevented the monsoon trough from moving over the continent. Beginning on the 15th, a surface based low pressure system formed over central Queensland and began moving to the northwest in the ensuing days. At the middle levels of the atmosphere the monsoon trough began shifting south to meet the surface low. This caused the onset of the North Australian Monsoon on the 17th of January. This came about three weeks later than usual, but still within the standard deviation of the the monsoon timing.

This first monsoon burst was quite brief across the Top End. By 19 January, two low pressure systems had formed over northeastern Australia within the monsoon trough, one over eastern Australia that would eventually become tropical cyclone Oswald and the other over northwestern Australia that would
eventually become tropical cyclone Peta. On the 21st tropical cyclone Oswald formed over the Gulf of Carpentaria and then made landfall on the western shores of the Cape York Peninsula. Over the next week ex-tropical cyclone Oswald moved south along the Queensland coast bringing high winds and
flooding rains to the area. In the meantime, on the 23rd, tropical cyclone Peta formed just of the northwest WA coast and tracked to the south west. With these two tropical systems to either side of the Northern Territory for the last week of January, the Top End experienced a lull in monsoon activity (scant rainfall and high temperatures) even under the influence of the monsoon trough.

March 2013: Wet weather finally arrives to the Top End

The wet season up to the end of February was hot and dry with many locations having the lowest wet season rainfall on record to that point in the season. In March, especially the last half of March, wet, monsoonal weather finally arrived in the Northern Territory and increased rainfall totals. The Madden-Julian Oscillation (MJO) was the main driver for the monsoon activity and general wet weather in the early part of the month. The MJO stalled over Australian longitudes which provided an extended period for a monsoon trough to form. Following another short break period mid-month, the passage of a westward moving equatorial Rossby wave during the last week of March revived the monsoon trough. A slow-moving, weak tropical low formed within the monsoon trough and moved along the north coast bringing heavy rainfall to most of the Top End (focused over the western Top End) during the Easter holiday weekend (28 March-1 April). This last burst of heavy rainfall lowered rainfall deficits across the northern NT. Many locations that were sitting below their previous lowest recorded wet season rainfall totals jumped above previous records, like Gove Airport, or closer to long-term means.

When comparing wet season (October to April) rainfall totals, the wettest overall was Geriatric Park with 1660.6 mm, followed by Edith Farms Road with 1646.1 mm, and then Walker Creek with 1613.6 mm. Meanwhile, The driest overall for the season was Bond Springs Turnoff with 46.5 mm, followed by Jervois with 70.4 mm, and then by Kulgera with 72.4 mm. Three sites had their lowest total October to April rainfall on record, these were Dum-In-Mirrie, Wagait Beach and Darwin Hospital. Dum-In-Mirrie and Wagait Beach recorded less than 1 metre of rainfall this season.

The wettest single day was at Mataranka Airstrip with 262.1 mm on 29 Mar 2013 (a new daily rainfall record for them), followed by Diljin Hill with 245.0 mm on 3 Mar 2013, and then Fergusson River with 239.0 mm on 30 Mar 2013.

Maximum temperature: Hottest wet season on record for many sites

Alice Springs Airport, Darwin Airport, Gove Airport, Jabiru Airport and Tindal RAAF, among other sites, all experienced their highest October to April mean daily maximum temperature on record. The hottest temperature reached anywhere in the NT this season was 46.7 °C at Walungurru with on 9 Jan 2013, and at Rabbit Flat on 25 Jan 2013. This set a new high October to April temperature record for both of these site where the previous records were 46.2 °C at Walungurru set on 28 January 2011 and 46.3 °C at Rabbit Flat set on 6 December 2004. Walungurru had a few days near this record with 46.6 °C on 8 Jan 2013 and again on 16 Jan 2013. This came at at time when several locations in the Alice Springs district were experiencing a prolonged heatwave. Walungurru endured 17 consecutive days above 42 °C from 1 January to 17 January 2013 of which 5 consecutive days were above 45 °C from 7 January to 11 January, inclusive. When averaged across the whole season, the warmest days on average were at Rabbit Flat with 38.7 °C, followed by Walungurru with 38.4 °C, followed by Brunette Downs with 37.9 °C. Victoria River Downs saw their warmest wet season in 21 years with a mean daily maximum temperature of 37.6 °C.

January was exceptionally hot across the NT (as well as the entire country). January set a new record for mean temperature, reaching 38.9 °C (both night-time and daytime temperatures combined) and also for the highest mean maximum temperature on record with 32.0 °C, which is 2.6 °C above the norm. Both existing records for the NT were set in 1971. Across the territory, 13 stations recorded their hottest January on record for mean temperatures. Such records were driven primarily by an strong sub-tropical ridge which included a hot, dry airmass that moved slowly across the continent resulting in really hot daytime temperatures. Of the 13 stations that recorded their highest mean maximum temperatures for the month, 12 of them also measured their hottest January daily maximum temperature. Gove with a mean maximum temperature of 33.3 °C, Tindal with 36.7 °C and Yulara with 41.3 °C were among the stations that broke their January record.

With a maximum temperature of 46.4 °C on the 11th (amidst the heat wave that perdured in the first half of the month), Yulara Aero equaled its hottest January day on record set in 2011. This was 0.6 °C shy of the hottest day ever recorded in Yulara for any given month. Further north, Tennant Creek hit the 44.2 °C mark on the 25th, making it the hottest January day in 44 years worth of records.

There were no low maximum temperature records set this season, but the coolest days on average were at McCluer Island with 31.6 °C, followed by Darwin Harbour with 32.5 °C, and then Ngayawili and Point Fawcett with 32.8 °C. The coldest days, this season, all occurred in the Alice Springs District in the last week of March as a passing cold front clipped the southern border of the NT. Yulara Aero saw the coolest daily maximum temperature 16.4 °C on 30 Mar 2013, followed by Kulgera with 18.2 °C on 28 Mar 2013, and then Curtin Springs with 19.0 °C on 30 Mar 2013.

An exceptional heat wave in early January

A heat wave early in January was exceptional in its extent and duration affecting most of Australia. In the southern NT, Alice Springs broke the record for the longest streak of days above 40 °C. From the 1st to the 17th inclusive, daytime temperatures at the Alice Springs airport rose over the 40 °C mark, surpassing the previous record streak of 12 days over 40 °C set in 2006. Although Alice Springs failed to break the record of the hottest January day set in 1960 with 45.2 °C, it manage to break the January mean maximum temperature record with 40.1 °C. This is 0.1 degrees warmer than the previous record of 40.0 °C set in January 2006. To the south of Alice Springs, Yulara Aero surpassed the 44.0 °C mark 10 days in a row (4th to the 13th inclusive), breaking their previous record streak of days above 44.0 °C of four days set in 1998. Walungurru endured 17 consecutive days above 42 °C from 1 January to 17 January 2013 of which 5 consecutive days were above 45 °C from 7 January to 11 January, inclusive.

Minimum temperature

October was the only month to see generally below average minimum temperatures this season. For all other months the mean daily minimum temperatures were above average to very much above average, with a few new high minimum temperature records. Jabiru experienced their highest October to April mean daily minimum temperature on record with a mean daily minimum of 25.0 °C, passing the previous record of 24.9 set in the 2006/2007 wet season. Walungurru tied their previous highest wet season minimums with a mean daily minimum of 24.6 °C.

January 2013 was an especially warm month for minimum temperatures. The January mean daily minimum for the whole of the NT was 25.0 °C. Although this is only, 1.3 °C above the norm, 12 stations across the Territory managed to register their warmest January nights on record. On average, nights in January 2013 were the warmest since January 2008. Particularly warm, was the night preceding Australia Day (26 January) in which Jabiru, Gove, Tindal, Batchelor and Middle Point recorded their warmest January night on record. It was also on this night (preceding 26th of January 2013) that four Top End sites all measured their warmest wet season (October to April) night on record. These were: Mango Farm with 28.0 °C (previous record 27.4 °C, 6 January 1998), Batchelor Aero with 27.8 °C (previous 27.1 °C, 6 January 1998), Groote Eylandt Airport 30.2 °C (previous record 30.0 °C, 3 December 2007), and Middle Point with 27.6 °C (previous record 27.0 °C, 29 January 2006).

Although not new records, the warmest nights this wet season were at Walungurru with 32.8 °C on 22 Jan 2013, followed by Jervois with 32.5 °C on 12 Jan 2013, and then again at Walungurru with 32.1 °C on 24 Jan 2013. The warmest nights on average for this wet season were at McCluer Island with 26.9 °C, followed by Cape Don with 26.8 °C, and then Centre Island and East Island with 26.5 °C.

While no records were set for low minimum temperatures, this season, the coldest night was at Alice Springs Airport with 4.0 °C on 13 Oct 2012, followed by Arltunga with 4.1 °C on 27 Apr 2013, and again at Arltunga with 4.8 °C on 13 Oct 2012. The coolest nights on average were at Alice Springs Airport with 18.4 °C, followed by Arltunga with 19.0 °C, and then Kulgera with 19.2 °C.

Wind

The strongest wind gust was measured at Lajamanu with 107 km/h on 18 Feb 2013, followed by Cape Wessel with 106 km/h on 20 Jan 2013.

Further information

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

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Extremes in October to April 2012-13
Hottest day	46.7 °C at Walungurru on 9 Jan 2013 46.7 °C at Rabbit Flat on 25 Jan 2013
Warmest days on average	38.7 °C at Rabbit Flat
Coolest days on average	31.6 °C at McCluer Island
Coldest day	16.4 °C at Yulara Aero on 30 Mar 2013
Coldest night	4.0 °C at Alice Springs Airport on 13 Oct 2012
Coolest nights on average	18.4 °C at Alice Springs Airport
Warmest nights on average	26.9 °C at McCluer Island
Warmest night	32.8 °C at Walungurru on 22 Jan 2013
Warmest on average overall	31.5 °C at Walungurru
Coolest on average overall	26.6 °C at Arltunga
Wettest overall	1660.6 mm at Geriatric Park
Driest overall	46.5 mm at Bond Springs Turnoff
Wettest day	262.1 mm at Mataranka Airstrip on 29 Mar 2013
Highest wind gust	107 km/h at Lajamanu on 18 Feb 2013

Extremes Maps Records Summaries Important notes the top

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Maps
	Observed	Anomaly	Decile rank
Total rainfall

Click on a map to show it full size in a pop-up window

Month by month
Rainfall rank	Maximum temperature rank	Minimum temperature rank
October
November
December
January
February
March
April
Rainfall rank	Maximum temperature rank	Minimum temperature rank

 

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Record highest October to April daily rainfall
	Highest daily rainfall in October to April 2012-13 (mm)		Previous wettest for October to April		Years of record
Dorisvale	226.0	on 30 Mar 2013	201.0	on 2 Mar 2000	30
Mataranka Airstrip	262.1	on 29 Mar 2013	179.0	on 26 Jan 1998	27
Walker Creek	197.4	on 4 Mar 2013	178.8	on 19 Feb 2008	21
Upper Waterhouse River	182.4	on 31 Mar 2013	136.6	on 5 Apr 2006	15
Cave Creek Station	202.0	on 29 Mar 2013	135.0	on 30 Oct 2010	11
Coodardie	201.0	on 29 Mar 2013	138.0	on 24 Dec 2008	11

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Record lowest total October to April rainfall
	Total rainfall for October to April 2012-13 (mm)	Previous driest for October to April		Years of record	Average for October to April
Dum In Mirrie AWS	928.0	1095.6	in 2001	14	1730.6
Darwin Hospital	1178.0	1240.8	in 2001	11	1709.8
Wagait Beach	953.9	1107.4	in 1989	11	1776.6

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Record highest October to April temperature
	Highest temperature in October to April 2012-13 (°C)		Previous warmest for October to April		Years of record	Average for October to April
Curtin Springs	46.4	on 11 Jan 2013	46.0	on 17 Feb 1992	49	34.2
Watarrka	45.3	on 12 Jan 2013	= 45.3	on 21 Dec 1990	23	34.9
Rabbit Flat	46.7	on 25 Jan 2013	46.3	on 6 Dec 2004	17	37.1
Walungurru	46.7	on 9 Jan 2013	46.2	on 28 Jan 2011	12	36.8

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Record highest October to April mean daily maximum temperature
	Mean daily maximum temperature for October to April 2012-13 (°C)	Previous warmest for October to April		Years of record	Average for October to April
Alice Springs Airport	35.7	35.4	in 2004	70	33.2
Darwin Airport	33.3	= 33.3	in 2004	70	32.4
Jervois	36.8	36.7	in 2004	40	35.2
Centre Island	34.4	34.3	in 2004	37	33.3
Gove Airport	33.0	32.6	in 1989	32	31.9
Jabiru Airport	36.1	36.0	in 2004	32	34.9
Kulgera	34.6	34.5	in 2006	31	32.9
Yulara Aero	36.4	36.1	in 2004	24	34.6
Tindal RAAF	36.2	= 36.2	in 1987	23	35.1
Douglas River	35.9	= 35.9	in 2004	19	34.9
Borroloola	36.2	35.9	in 2001	18	35.0
Dum In Mirrie AWS	32.9	32.5	in 2009	13	32.1
Ngayawili	32.8	32.5	in 2001	13	32.1
Point Fawcett	32.8	32.6	in 2002	13	32.1
Arltunga	34.3	34.2	in 2004	11	32.8
Middle Point AWS	35.6	35.2	in 2004	11	34.5

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Record highest October to April daily minimum temperature
	Highest daily minimum temperature in October to April 2012-13 (°C)		Previous warmest for October to April		Years of record	Average for October to April
Mango Farm	28.0	on 26 Jan 2013	27.4	on 6 Jan 1998	33	23.2
Batchelor Aero	27.8	on 26 Jan 2013	27.1	on 6 Jan 1998	18	23.4
Groote Eylandt Airport AWS	30.2	on 26 Jan 2013	30.0	on 3 Dec 2007	14	23.6
Middle Point AWS	27.6	on 26 Jan 2013	27.0	on 29 Jan 2006	12	23.5

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Record highest October to April mean daily minimum temperature
	Mean daily minimum temperature for October to April 2012-13 (°C)	Previous warmest for October to April		Years of record	Average for October to April
Jabiru Airport	25.0	24.9	in 1997	33	24.4
Walungurru	24.6	= 24.6	in 2006	10	23.5

Extremes Maps Records Summaries Important notes the top

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Summary statistics for October to April 2012-13
	Maximum temperatures for October to April (°C)				Minimum temperatures for October to April (°C)				Rainfall for October to April (millimetres)
	Mean for October to April 2012-13	Diff from average	Highest for October to April 2012-13		Mean for October to April 2012-13	Diff from average	Lowest for October to April 2012-13		Total for October to April 2012-13	Average for October to April	Rank of October to April 2012-13	Fraction of October to April average
Darwin-Daly (district 14GA)
Batchelor Aero	34.4	+0.4	38.6	4 Nov 2012	23.5	+0.1	16.2	13 Apr 2013	1409.8	1555.5	average	91%
Bradshaw	37.2	+0.9	42.3	7 Dec 2012	24.6	+0.1	15.6	3 Oct 2012	997.4	935.6	average	107%
Cape Don	33.6		36.9	7 Dec 2012	26.8		22.9	28 Jan 2013	1242.2	1226.9	average	101%
Central Arnhem Plateau	33.9		39.9	6 Dec 2012	22.9		16.3	2 Oct 2012	1168.2
Croker Island Airport	32.9		36.3	11 Dec 2012	25.7		20.5	14 Mar 2013	1247.6
Darwin Airport	33.3	+0.9	36.6	13 Oct 2012	25.0	+0.2	19.4	13 Apr 2013	1399.3	1682.8	low	83%
Darwin NTC AWS	32.5		35.3	27 Nov 2012	26.0		20.4	3 Dec 2012
Douglas River	35.9	+1.0	40.9	27 Oct 2012	23.1	+0.1	14.6	27 Apr 2013	980.4	1261.2	low	78%
Dum In Mirrie AWS	32.9	+0.8	36.0	25 Apr 2013	25.5	+0.1	18.4	13 Apr 2013	928.0	1730.6	lowest	54%
Jabiru Airport	36.1	+1.2	40.5	31 Oct 2012	25.0	+0.6	19.5	13 Apr 2013	1193.4	1523.7	low	78%
Katherine Country Club	36.6		41.3	6 Dec 2012	23.8		14.8	27 Apr 2013	1071.5
Mango Farm	35.1	+0.3	39.8	10 Oct 2012	23.4	+0.2	15.3	3 Oct 2012	1217.6	1374.8	average	89%
McCluer Island	31.6		34.6	19 Dec 2012	26.9		22.4	14 Mar 2013	1089.6	1131.7	average	96%
Middle Point AWS	35.6	+1.1	39.5	27 Nov 2012	23.2	-0.3	15.1	13 Apr 2013	919.4	1379.7	v low	67%
Noonamah AWS	35.4		39.1	27 Oct 2012	23.6		16.0	13 Apr 2013	1264.0
Oenpelli Airport	35.6		40.8	4 Dec 2012	24.4		17.9	2 Oct 2012	1132.6
Pirlangimpi	33.4	+0.9	36.7	4 Dec 2012	24.3	+0.4	20.3	14 Apr 2013	1575.6	1937.8	low	81%
Point Fawcett	32.8	+0.7	35.2	9 Dec 2012	24.5	-0.4	18.6	27 Apr 2013	995.2	1500.1	v low	66%
Tindal RAAF	36.2	+1.1	41.0	1 Nov 2012	23.8	+0.1	15.0	30 Apr 2013	1068.2	1062.1	average	101%
Arnhem (district 14BC)
Cape Wessel	33.1		36.6	10 Jan 2013	26.1		21.3	14 Mar 2013
Gove Airport	33.0	+1.1	36.2	25 Jan 2013	23.7	0.0	17.7	6 Oct 2012	855.8	1300.9	v low	66%
Groote Eylandt Airport AWS	34.0	+0.7	38.1	25 Jan 2013	23.7	+0.1	15.0	2 Oct 2012	1031.4	1326.5	low	78%
Maningrida Aero	33.4		36.9	25 Jan 2013	24.6		16.9	2 Oct 2012	947.4
Ngayawili	32.8	+0.7	36.3	2 Dec 2012	24.8	+0.2	19.9	13 Apr 2013	1004.2	1482.8	low	68%
North East Island	33.1		35.5	14 Jan 2013	26.5		22.5	3 Oct 2012	752.0	815.3	average	92%
Roper-Mcarthur (district 14DE)
Borroloola	36.2	+1.2	43.3	6 Dec 2012	23.5	+0.2	13.7	14 Oct 2012	842.6	938.8	average	90%
Centre Island	34.4	+1.1	39.7	27 Jan 2013	26.5	+0.2	22.0	12 Oct 2012
Daly Waters AWS	37.5	+1.6	43.4	25 Jan 2013	22.4	-0.3	9.9	14 Oct 2012	583.0	649.4	average	90%
McArthur River Mine	37.6	+1.1	44.1	6 Dec 2012	24.3	+0.9	11.7	14 Oct 2012	607.6	751.9	average	81%
Ngukurr AWS	37.5		43.7	6 Dec 2012	24.9		16.5	14 Oct 2012	664.4
Wollogorang			42.5	28 Jan 2013	22.2	-0.3	10.0	14 Oct 2012
Victoria (district 14F)
Timber Creek	37.4	+0.9	43.0	7 Dec 2012	24.2	+0.1	13.9	29 Apr 2013	719.5	955.0	low	75%
Victoria River Downs	37.6	+1.2	43.8	7 Dec 2012	23.5	0.0	11.3	16 Oct 2012	543.1	640.9	average	85%
Barkly (district 15A)
Brunette Downs	37.9	+1.5	42.9	7 Mar 2013	23.1	+0.4	11.5	13 Oct 2012	244.9	392.5	low	62%
Tennant Creek Airport	36.8	+1.6	44.2	25 Jan 2013	23.7	+0.4	14.2	12 Oct 2012	332.6	441.6	average	75%
Alice Springs (district 15B)
Alice Springs Airport	35.7	+2.5	44.4	12 Jan 2013	18.4	+0.5	4.0	13 Oct 2012	129.2	218.3	low	59%
Arltunga	34.3	+1.5	43.2	12 Jan 2013	19.0	+0.7	4.1	27 Apr 2013	121.8	239.6	low	51%
Curtin Springs	36.0	+1.8	46.4	11 Jan 2013	20.0	+1.7	6.0	3 Oct 2012	104.5	171.4	average	61%
Jervois	36.8	+1.6	45.5	11 Jan 2013	21.1	+1.9	8.4	13 Oct 2012	70.4	237.1	v low	30%
Kulgera	34.6	+1.7	44.9	8 Jan 2013	19.2	+0.8	5.3	2 Oct 2012	72.4	195.1	v low	37%
Rabbit Flat	38.7	+1.6	46.7	25 Jan 2013	21.7	+0.3	7.8	3 Oct 2012	276.0	440.2	average	63%
Walungurru	38.4	+1.6	46.7	9 Jan 2013	24.6	+1.1	13.8	11 Oct 2012	133.0	213.7	average	62%
Yulara Aero	36.4	+1.8	46.4	11 Jan 2013	20.2	+1.4	6.3	3 Oct 2012	86.8	220.8	low	39%

Extremes Maps Records Summaries Important notes the top

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Further information

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

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