Thursday 4th August 2005

MONTHLY CLIMATE SUMMARY - NT REGIONAL OFFICE

Rainfall deficiencies continue despite July rains in southern NT

Two significant cloud bands, caused by mid and upper level troughs, brought widespread above average rainfall to the Alice Springs district this month. The first band affected the Territory at the end of the first week, the second at the start of the second week. Although this rain significantly reduced medium to long term rainfall deficiencies in the Alice Springs District, some areas of the Alice Springs, Victoria River Downs and Barkly districts still experience severe, to lowest on record rainfall deficiencies.

Most of the Territory also experienced above average maximum and minimum temperatures this month.

Rainfall

Rainfall was very much above average over most of the Alice Springs district, with many stations recording rainfall that was in the highest 10% of records. Both the Territory Grape Farm and Gemtree Park broke their highest monthly rainfall records over three rainfall days. The highest daily and monthly rainfall totals of 80.6mm and 82.5mm respectively, were both recorded at Yuendumu.

Active Gulf lines and many days of moist easterly winds in the north produced showers and some areas of above average rainfall around the Gulf and northeast coast.

Maximum Temperatures

Maximum temperatures were close to average or slightly below average in the southern Alice Springs District due to the cloud bands. Maximum temperatures were generally very much above average over the remainder of the Territory. Highest daily maximum temperature records were exceeded at McArthur River Mine and Lajamanu, with McArthur River Mine recording 34.8oC on the 7th and Lajamanu recording 33oC on the 13th. Lajamanu also exceeded its record highest mean maximum temperature for the month recording 28.5oC. The maximum temperature anomaly was up to 1 degree below average in the far south and about 1 to 3 degrees above average over the remainder.

Interestingly, on the 6th, most stations in the Alice Springs district recorded their highest daily temperatures for the month in a warm northeasterly flow. Then on the 7th, as cloud covered the area and rain fell, most stations in the south recorded their lowest daily temperatures for the month. Stations in the Alice Springs district also recorded high daily maximum temperatures during the last week in dry southeasterly flow and fine conditions due to a ridge over southern Australia.

The highest daily maximum temperature of 35.6oC was recorded at Douglas River on the 6th. The lowest daily maximum temperature of 10oC was recorded at Kulgera on the 11th.

Minimum Temperatures

Minimum temperatures were above, or very much above average over the whole of the Territory this month, with monthly and daily temperature records broken at Ngukurr and Lajamanu. Minimum temperatures were about 1 to 3 degrees above the mean over much of the territory and up to 4 or 5 degrees above the mean in the southern Victoria River Downs district and near Rabbit Flat.

The main cause of these warmer than average minimum temperatures was overnight cloud cover during the two cloud band events mentioned previously and also from another cloud band that formed towards the end of the month. For a period of a few days, a thin layer of cloud trapped under a temperature inversion covered most of the territory preventing overnight temperatures from falling. This cloud band produced no rain.

Nearly all stations north of the Alice Springs district recorded their coolest daily minimum temperatures on the first day of the month, due to fine and dry conditions produced from a ridge pushing into central Australia extending from a high pressure system near Perth.

The lowest minimum temperature of 0.2oC was recorded at Alice Springs on the 4th. The highest daily minimum temperature of 24.9oC occurred at Bradshaw on the 24th.

Maps displaying recent temperature and rainfall patterns can be seen on the Bureau’s web site.

A table of Territory extremes, some new records, and summaries for sites across the State appear below.

Extremes

Weather extremes during July 2005
Highest temperature
Hottest day		 35.6 °C Douglas River on 6th
Highest mean daily maximum temperature
Warmest days on average		 33.7 °C Middle Point AWS
Lowest mean daily maximum temperature
Coolest days on average		 18.6 °C Kulgera
Lowest daily maximum temperature
Coldest day		 10.0 °C Kulgera on 11th
Lowest temperature
Coldest night		 0.2 °C Alice Springs Airport on 4th
Lowest mean daily minimum temperature
Coldest nights on average		 5.2 °C Alice Springs Airport
Highest mean daily minimum temperature
Mildest nights on average		 22.6 °C Warruwi
Highest daily minimum
Warmest night		 24.9 °C Bradshaw on 24th
Highest total rainfall
Wettest overall		 82.5 mm Yuendumu
Highest daily rainfall
Wettest day		 80.6 mm Yuendumu on 8th

Records

Record Highest Total Rainfall for July

Total rainfall
for July 2005 (mm) 		Previous highest
for July 		Years of
record
Territory Grape Farm *
34.2
22.4
in 1996
16
Gemtree Park *
30.6
22.0
in 2001
15
* indicates unconfirmed data


Record Highest Daily Rainfall for July

Highest Daily Rainfall
in July 2005 (mm) 		Previous highest
for July 		Years of
record
Yuendumu *
80.6
on 8th
74.0
on 8th in 1978
51
Territory Grape Farm *
33.0
on 8th
18.0
on 26th in 1996
16
Gemtree Park *
28.8
on 8th
10.4
on 18th in 1995
15
* indicates unconfirmed data


Record Lowest 14-month Cumulative Rainfall totals for June to July

Total rainfall
for June 2004 - July 2005 (mm) 		Previous lowest
for June - July 		Years of
record
Ali Curung *
129.4
171.7
in 1991
24
Mount Riddock *
151.9
190.5
in 1970
24
Ormiston Gorge *
140.8
160.6
in 1990
22
Alice Springs East Side *
132.0
173.6
in 1995
21
Hidden Valley *
234.4
292.6
in 1989
17
Palmer Valley *
91.2
113.6
in 1961
17
Gemtree Park *
175.2
187.8
in 1995
11
* indicates unconfirmed data


Record Highest Mean Maximum Temperature for July

Mean daily maximum
temperature
for July 2005 (°C) 		Previous highest
for July 		Years of
record
Lajamanu
28.5
28.3
in 2000
10


Record Highest Temperature for July

Highest temperature
in July 2005 (°C) 		Previous highest
for July 		Years of
record
McArthur River Mine
34.8
on 7th
34.7
on 24th in 1981
23
Lajamanu
33.0
on 13th
32.2
on 31st in 1971
10


Record Highest Mean Daily Minimum Temperature for July

Mean daily minimum
temperature
for July 2005 (°C) 		Previous highest
for July 		Years of
record
Lajamanu
12.5
11.1
in 2001
10


Record Highest Daily Minimum Temperature for July

Highest daily minimum
temperature
in July 2005 (°C) 		Previous highest
for July 		Years of
record
Ngukurr
23.0
on 26th
22.8
on 14th in 1962
10
Lajamanu
21.0
on 24th
18.6
on 4th in 1968
10


Summaries

Summary statistics for July 2005


 Maximum temperatures
for July
(°C)		 Minimum temperatures
for July
(°C)		 Rainfall
for July
(mm)
Mean for 2005 Difference from normal Highest for 2005 Mean for 2005 Difference from normal Lowest for 2005 Total for 2005 Normal total
Ali Curung
24.1
-0.5
29.8
9.0
+1.6
5.8
4
5
Alice Springs Airport
19.3
-0.4
27.1
5.2
+1.2
0.2
58
14
Alyangula Police
28.5
+0.5
32.0
19.2
+1.5
16.0
0
3
Arltunga
18.9

25.4
5.5

1.0
31
9
Batchelor Aero
33.3

35.2
17.7

9.9
0

Borroloola
31.1
+0.7
33.6
14.1
+2.0
8.9
0

Brunette Downs
28.0
+1.3
34.3
12.5
+2.0
7.3
0
5
Centre Island
27.1
+1.0
29.7
19.6
+1.2
17.8
2
2
Channel Point
    
32.0
    
13.4
0
0
Curtin Springs
19.7
-0.3
24.5
6.1
+2.5
0.6
55
12
Daly Waters AWS
30.9
+2.2
34.7
14.3
+2.1
7.0
0
2
Darwin Airport
31.9
+1.5
33.7
20.5
+1.2
15.9
0
1
Delamere Weapons Range
30.8

35.0
16.9

8.0
0

Douglas River
32.7
+1.1
35.6
15.1
+2.2
5.0
0
3
Dum In Mirrie AWS
31.2

32.8
19.6

12.1
0

Elliott
30.2
+1.8
35.5
13.9
+2.8
8.8
0
3
Gove Airport
28.4
+0.7
29.5
21.2
+1.1
17.2
26
20
Jabiru Airport
33.2
+1.5
35.2
19.7
+1.2
15.1
0
2
Jervois
21.5
-0.5
30.0
7.7
+2.7
4.0
13
13
Katherine Aviation Museum
31.2
+0.7
34.1
15.1
+2.2
6.5
0
1
Kidman Springs
31.6
+1.2
34.9
14.9
+2.5
6.8
0
3
Kulgera
18.6
-0.3
23.7
6.7
+1.9
2.0
50
11
Lajamanu
28.5
+2.0
33.0
12.5
+4.1
6.0
0
4
Larrimah
30.7
+1.4
34.2
14.1
+1.5
6.0
0
3
Mango Farm
32.8
+1.3
35.5
17.0
+2.1
10.5
0
3
Maningrida
31.1
+0.9
32.5
19.0
+1.7
14.2
7
2
McArthur River Mine
31.5
+1.7
34.8
14.0
+2.1
8.4
1
3
McCluer Island
27.6

29.4
23.9

22.1
0

Ngukurr
    
34.0
    
12.5
0
1
Oenpelli
33.3
+1.3
35.0
19.8
+1.5
13.9
0
2
Papunya
21.2

27.0
7.4

3.0
43
9
Point Fawcett
31.4

33.2
20.5

15.5
0

Rabbit Flat
26.5

31.4
10.5

4.2
0

Tennant Creek Airport
25.2
+0.6
31.4
13.5
+1.3
8.8
0
5
Territory Grape Farm
21.8
27.0
7.4
3.0
34
3
Timber Creek
31.8
+1.3
35.4
17.1
+2.2
8.6
0
2
Tindal RAAF
31.3
+1.4
33.9
15.6
+1.8
8.1
0
4
Victoria River Downs
30.2
+1.0
34.2
13.1
+2.1
5.3
0
3
Warruwi
29.8
+1.3
32.0
22.6
+1.5
21.0
0
2
Watarrka
20.7
-1.1
27.5
7.6
+1.4
2.0
50
14
Wave Hill
29.5
+1.1
33.7
13.5
+2.8
5.5
9
5
Wollogorang
30.2
+0.8
34.7
13.9
+2.5
7.2
0
2
Yuendumu
21.6
-0.2
26.6
7.7
+1.6
3.8
83
13
Yulara Aero
19.8
-0.7
24.3
6.0
+1.4
0.8
68
20

Further information

This statement has been prepared based on information available at 10 am on Thursday 4th August 2005. Although every effort has been made to check them, it is possible that results will change as new information becomes available.

Further information

The Daily Weather Observations lists daily temperatures and rainfall, plus many other meteorological variables, at more than 50 locations across the Territory (and over 700 across Australia). Data from the last 13 months are available free from this web site.

Climate and Consultative Services
Northern Territory Regional Office
Bureau of Meteorology
Phone (08) 8920 3813
Email climate.nt@bom.gov.au