MEDIA RELEASE  - Friday, 1 May 2009

April 2009 in the Northern Territory

Northeast to southeast winds prevailed over the Territory during April, with the monsoon trough being well offshore, or poorly developed, throughout the month. Tropical Cyclone Kirrily formed in the Arafura Sea, well north of the Territory coast late in April, but otherwise tropical weather activity generally had less than average impacts. A surge of southeasterly winds progressed to the north coast by the end of the month, heralding the end of the wet season and the start of the “The Dry”, which officially begins on May 1.

Rainfall

Over the Territory as a whole, the area-averaged rainfall was 13.1 mm, less than half of the long-term average of 27.9 mm. There were two main rain periods over the Territory during April. The first affected much of the Top End, extending to the northeast border regions, during the second week of April, and was mostly associated with tropical features in the north. The second period was the third week of the month, and was again mostly associated with tropical weather features in the north, and was mostly confined to the Top End. During the later part of this period, rainfall also occurred in southwest parts of the Territory associated with a couple of frontal systems moving through southern parts of the continent.

The wettest overall was 232.4 mm at Groote Eylandt Airport AWS, followed by 145.6 mm at Alyangula Police, followed by 140.0 mm at Yirrkala Tropical Gardens.

The wettest single day was 105.0 mm at Bulman AWS on the 11th, followed by 61.2 mm at Groote Eylandt Airport AWS on the 19th, followed by 60.2 mm at Benmara on the 13th.

Some sites had their highest April daily rainfall on record.

Maximum temperature

Predominately dry sunny conditions led to above average maximum temperatures this month, with some new high temperature records set about the Top End and McArthur River regions. The area-averaged maximum temperature was 33.6°C, which was 0.9°C above the long-term average.

The hottest day was 40.0°C at Walungurru AWS on the 1st, followed by 39.6°C at Rabbit Flat on the 1st, followed by 39.3°C at Rabbit Flat on the 2nd.

The warmest days on average were 37.5°C at Bradshaw AWS, followed by 36.9°C at Timber Creek, followed by 36.7°C at Douglas River.

The coolest days on average were 29.1°C at Alice Springs Airport, followed by 29.5°C at Yulara Aero AWS, followed by 29.9°C at Curtin Springs.

The coldest day was 21.8°C at Kulgera on the 8th, followed by 22.0°C at Kulgera on the 24th, followed by 22.7°C at Yulara Aero AWS on the 24th.

Some sites had their highest April temperature on record.

Some sites had their highest April mean daily maximum temperature on record.

Minimum temperature

Minimum temperatures were mostly warmer than average this month. The area-averaged minimum temperature was 22.0°C, which was 0.3°C above the long-term average. Some areas in the Alice Springs Region, and also the northwest Top End, saw anomalies of more than 1°C.

The coldest night was 6.1°C at Arltunga on the 25th, followed by 6.4°C at Watarrka on the 26th, followed by 7.0°C at Curtin Springs on the 25th.

The coolest nights on average were 13.4°C at Alice Springs Airport, followed by 13.8°C at Kulgera, followed by 14.5°C at Curtin Springs.

The warmest nights on average were 26.1°C at Centre Island AWS.

The warmest night was 28.5°C at Dum In Mirrie AWS on the 15th.

Some sites had their warmest April night (highest daily minimum temperature) on record.

Wind

The strongest wind gust was 93 km/h at Darwin Airport on the 7th, followed by 69 km/h at Dum In Mirrie AWS on the 4th, followed by 67 km/h at Central Arnhem Plateau on the 2nd and McCluer Island on the 20th.


Extremes

Hottest day
Highest temperature
40.0°C at Walungurru AWS on the 1st
Warmest days on average
Highest mean daily maximum temperature
37.5°C at Bradshaw AWS
Coolest days on average
Lowest mean daily maximum temperature
29.1°C at Alice Springs Airport
Coldest day
Lowest daily maximum temperature
21.8°C at Kulgera on the 8th
Coldest night
Lowest temperature
6.1°C at Arltunga on the 25th
Coolest nights on average
Lowest mean daily minimum temperature
13.4°C at Alice Springs Airport
Warmest nights on average
Highest mean daily minimum temperature
26.1°C at Centre Island AWS
Warmest night
Highest daily minimum temperature
28.5°C at Dum In Mirrie AWS on the 15th
Wettest overall
Highest total rainfall
232.4 mm at Groote Eylandt Airport AWS
Wettest day
Highest daily rainfall
105.0 mm at Bulman AWS on the 11th
Highest wind gust
93 km/h at Darwin Airport on the 7th

Records

Record highest April daily rainfall
Highest daily rainfall
in 2009 (mm)
Previous highest Years of
record
Gallipoli 41.2 on the 12th 29.7 on the 23rd in 1970 31



Record highest April temperature
Highest temperature
in 2009 (°C)
Previous highest Years of
record
Centre Island AWS 36.3 on the 5th 36.0 on the 6th in 1981 34
McArthur River Mine 39.1 on the 4th 39.0 on the 24th in 2002 26
Black Point 34.0 on the 14th = 34.0 on the 28th in 2002 15
Borroloola AWS 38.1 on the 4th 37.8 on the 24th in 2002 13



Record highest April mean daily maximum temperature
Mean daily maximum
temperature
for 2009 (°C)
Previous highest Years of
record
Jabiru Airport AWS 36.3 36.0 in 2003 30
Tindal RAAF AWS 35.4 = 35.4 in 2002 21
Black Point 32.8 32.4 in 2002 15



Record highest April daily minimum temperature
Highest daily minimum
temperature
in April 2009 (°C)
Previous highest
for April
Years of
record
Channel Point 27.7 on the 9th 26.8 on the 25th in 2006 14
Delamere Weapons Range AWS 25.2 on the 25th 25.0 on the 4th in 2006 11




Summaries

This table is very wide and may not fit if printed.

Summary statistics for April 2009
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean Diff
from
average
Highest Mean Diff
from
average
Lowest Total Rank Fraction of
average
Darwin-Daly (district 14GA)
Batchelor Aero AWS 35.6   36.7 18th 21.8   14.7 30th 0.4 very low 0%
Black Point 32.8 +1.3 34.0 14th 25.3 +0.4 23.3 4th 46.8 average 43%
Bradshaw AWS 37.5   39.0 4th 23.0   14.6 30th 0
Cape Don AWS 32.2   33.5 18th 25.9   24.2 4th 101.4 average 69%
Central Arnhem Plateau AWS 33.7   35.7 4th 21.5   17.2 30th 27.0
Channel Point 33.3 +1.0 34.9 21st 24.4 +1.0 20.5 29th 5.2 very low 4%
Darwin Airport 33.6 +0.9 35.1 26th 24.6 +0.6 21.5 29th 63.4 average 65%
Delamere Weapons Range AWS 35.6 +1.4 37.1 15th 21.6 +0.3 15.6 29th 0.4 average 2%
Douglas River 36.7 +2.1 38.4 17th 20.8 +0.4 14.0 29th 0 lowest 0%
Dum In Mirrie AWS 33.2   34.9 18th 24.9   19.2 30th 41.0 average 35%
Jabiru Airport AWS 36.3 +1.9 37.3 5th 24.0 +0.5 21.7 30th 34.0 average 42%
Katherine Aviation Museum 35.4 +1.2 37.1 17th 20.6 −0.4 12.9 30th 0 lowest 0%
Mango Farm 36.1 +1.7 37.5 17th 21.9 +0.2 17.5 30th 0 lowest 0%
McCluer Island AWS 31.3   32.6 16th 26.5   24.6 24th 52.6 average 30%
Middle Point AWS 35.3   36.4 14th 22.9   16.9 30th 51.2
Noonamah AWS 35.8   37.6 18th 23.0   17.3 30th 6.6
Pine Creek Council 35.2   36.9 17th 22.4   18.6 29th 0
Pirlangimpi AWS 33.7 +1.1 34.9 14th 23.9 +1.0 20.6 30th 72.2 low 46%
Point Fawcett AWS 33.0   34.2 14th 23.2   19.0 30th 8.2 low 6%
Port Keats Aero 35.7   37.6 18th 22.9   18.0 30th 55.6
Tindal RAAF AWS 35.4 +1.7 37.2 15th 20.5 −0.3 13.9 30th 0 lowest 0%
Arnhem (district 14BC)
Alyangula Police 32.1 +0.3 34.0 6th 23.6 +0.6 21.4 29th 145.6 average 81%
Gove Airport 31.6 +0.8 33.6 5th 23.7 +0.4 21.3 1st 108.0 average 46%
Groote Eylandt Airport AWS 32.9   35.3 1st 21.6   17.7 28th 232.4
Maningrida Aero AWS 33.7   35.5 15th 23.7   20.1 28th 18.8
Milingimbi AWS 33.6   34.9 27th 24.1   20.7 28th 32.0
Ngayawili AWS 32.4   33.8 15th 23.8   21.5 2nd 95.8
Warruwi AWS 32.6 +1.0 34.9 16th 25.4 +0.4 22.5 22nd 42.0 average 34%
Roper-Mcarthur (district 14DE)
Borroloola AWS 35.8 +2.0 38.1 4th 20.0 −0.7 13.0 29th 0 lowest 0%
Bulman AWS 34.9   36.7 4th 20.2   16.0 28th 117.6
Centre Island AWS 33.1 +1.1 36.3 5th 26.1 +0.8 22.7 29th 19.2 average 21%
Daly Waters AWS 35.4 +1.7 37.1 3rd 18.8 −1.1 14.7 29th 0.2 average 1%
Larrimah 35.1 +1.2 36.8 4th 19.2 −0.6 10.5 29th 2.8 average 8%
McArthur River Mine 36.5 +1.8 39.1 4th 21.5 +0.9 14.2 29th 0.8 low 3%
Ngukurr 35.3 +1.3 37.5 5th 22.4 +0.4 18.0 29th 2.4 low 4%
Wollogorang 34.7 +0.9 37.9 3rd 19.8 0.0 13.0 28th 52.6 high 130%
Victoria (district 14F)
Kidman Springs 36.6 +1.1 38.0 15th 20.3 −0.7 11.5 30th 0.6 average 2%
Lajamanu AWS 36.0 +2.5 38.8 2nd 18.4 +0.3 11.0 29th 0 lowest 0%
Timber Creek 36.9 +1.8 38.3 15th 20.5 −0.8 12.9 29th 0 lowest 0%
Victoria River Downs 36.2 +1.8 38.2 3rd 19.7 −0.2 11.1 30th 4.6 average 20%
Wave Hill 35.9 +1.6 38.0 3rd 18.7 −0.2 10.1 30th 1.8 average 9%
Barkly (district 15A)
Elliott 34.7 +0.3 37.1 2nd 19.7 +0.1 14.5 29th 0 lowest 0%
Tennant Creek Airport 33.0 +1.4 36.4 1st 21.0 +0.6 15.5 29th 1.0 average 6%
Alice Springs (district 15B)
Alice Springs Airport 29.1 +0.9 35.4 1st 13.4 +0.8 7.6 29th 0 lowest 0%
Curtin Springs 29.9 +0.8 37.4 1st 14.5 +1.2 7.0 25th 3.8 average 23%
Jervois 31.1 +0.6 36.3 23rd 15.6 +1.4 8.8 28th 0 lowest 0%
Kulgera     34.8 2nd 13.8 0.0 7.5 27th 14.5 high 99%
Papunya 31.8   38.1 1st 16.5   11.0 29th 0.5 average 3%
Rabbit Flat 36.0 +1.9 39.6 1st 17.4 +0.3 11.6 30th 0 lowest 0%
Territory Grape Farm AWS 31.3 +0.7 36.2 1st 15.0 +0.2 9.6 30th 1.0 average 5%
Watarrka     37.5 1st 16.2 −0.5 6.4 26th 3.7 average 22%
Yuendumu 32.0 +2.1 37.3 1st 16.8 +1.2 11.5 26th 0 lowest 0%
Yulara Aero AWS 29.5 −0.4 37.6 1st 15.0 +0.6 7.2 24th 4.4 average 28%

Further information

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