Wednesday, 3 January 2007
SOUTH AUSTRALIAN MONTHLY CLIMATE SUMMARY - SA REGIONAL OFFICE
Dry December 2006 in South AustraliaDecember rainfall was mostly below to very much below average over much of the State with the exception of the far west where totals in parts were very much above average. December temperatures were above normal.
Rainfall totals were average to above average in the Far North District, average to below average in the North West District and generally average with pockets of below average rainfall in the North East District. Isolated readings of very much above average rainfall in the North West and Far North Districts were due to localised thunderstorm/shower activity. Rainfall totals throughout the Pastoral Districts ranged mostly between 0 mm, at Coober Pedy, and 15 mm, at Panaramitee. Isolated totals above 15 mm were confined to the Far North and North West Districts.
The highest rainfall reported over the Pastoral Districts was 41 mm at Nonning, in the North West District.
Rainfall totals over the Agricultural districts ranged from below to very much below average between Nullarbor and Streaky Bay, in the far west of the Western Agricultural District to above average over much of the Eyre Peninsula, in the same district, to below to very much below average over the eastern border districts. Parts in between recorded mostly average rainfall totals. Kangaroo Island was generally average to below average.
Rainfall totals over 50 mm were confined to isolated stations in the Western Agricultural and Upper North Districts. Rainfall totals mostly between 25 and 50 mm were confined to the Lower North and Mount Lofty Ranges Districts and also central parts of the Eyre Peninsula, in the Western Agricultural District. Rainfall totals below 15 mm were confined to most of the Lower Southeast and Riverland and the far west of the Western Agricultural District. Elsewhere totals were mostly between 15 and 25 mm.
The highest rainfall total for December was 53 mm, and was recorded at Melrose, in the Upper North and also at Winter Springs, in the Western Agricultural District.
Maximum temperatures were between near average and up to about 1°C above normal across most of the Pastoral Districts of South Australia
Mean maximum temperatures in the Pastoral Districts ranged from 31.3°C at Nonning to 36.8°C at Marree. The highest maximum temperature recorded was 43.0°C at Tarcoola on the 9th. Mean maximum temperatures in the Agricultural Districts ranged from 21.9°C at Robe to 32.1°C at Port Augusta Airport. The highest temperature recorded was 44.3°C at Ceduna on the 9th December.
Minimum temperatures were near average to about 1°C above average over the Pastoral districts. Mean minimum temperatures in the Pastoral Districts ranged from 13.1°C at Gluepot Station to 22.3°C at Moomba Airport. The lowest minimum temperature recorded in the Pastoral Districts was 4.9°C at Gluepot.
Minimum temperatures were near average over the northern Agricultural districts to about 1 to 2°C below average over southeastern parts. Mean minimum temperatures in the Agricultural Districts ranged from 8.2°C at Coonawarra to 17.6°C at Port Pirie. The lowest minimum temperature recorded in the Agricultural Districts was 1.1°C at Coonawarra on the 4th.
Significant Weather December 2006
On the 1st, a thunderstorm over the Northwest Pastoral produced a wind gust to 111 km/h at Oodnadatta.
A line of thunderstorms moved over Eyre Peninsula on the 21st and resulted in a wind gust to 110 km/h at Cleve and 91 km/h at Whyalla.
Large hail (2.5cm) was reported from a thunderstorm over Kenton Valley (Mount Lofty Ranges) on the 29th
Significant Fire Weather Days
The passage of a front and pre-frontal trough over South Australia on the 5th helped to produce extreme fire danger in 10 districts.
On the 8th, a large high in the Tasman directed northeasterly winds over South Australia that resulted in extreme fire danger in 8 districts.
The 9th saw extreme fire danger in 14 districts as a front moved over South Australia in the wake of the large high from the 8th.
Extreme fire danger was observed in 8 districts on the 30th as a large high in the Tasman Sea combined with a trough over South Australia to produce strong northeasterly winds.
Adelaide's rainfall for December 2006 is 16.8 mm, recorded on 5 days. This is 10.8 mm below the normal of 27.6 mm on 7 days. Last year 56.4 mm was recorded in December on 10 days. This is the driest December since 2002 when 9.0 mm was recorded. The total rainfall for the year is 287.8 mm and is well below the normal of 558.2 mm and is the driest year since records began at the Kent Town site in 1977. However, if we use the combined Adelaide record, this year's rainfall of 287.8 mm is the second driest since records commenced in 1839. The driest year on record was in 1967 when the total annual rainfall was 257.8 mm.
Adelaide's mean maximum temperature for December 2006 is 28.5°C, which is 1.7°C above the normal December mean maximum of 26.8°C. The mean December maximum last year was 27.3°C. Adelaide's mean maximum temperature for 2006 is 23.1°C, which is 1°C above the annual average of 22.1°C, and is the highest recorded at the Kent Town site. However, if we use the combined Adelaide record it is the 3rd highest average maxima since temperature records commenced in 1887. Last year the annual average maximum temperature was 22.8°C.
The mean minimum temperature for December 2006 is 15.6°C, which is equal to the normal December mean minimum of 15.6°C. Last December, the mean minimum was 16.0°C. Adelaide's mean minimum temperature for 2006 is 12.1°C, which is average for the Kent Town site. Last year the annual average minimum temperature was 12.4°C.
South Australian Weather Summary issued 3 January 2007: For further information please contact Bruce Brooks on (08) 8366 2698.