The daily weather log

September was a month of changeable weather. It began with normal temperatures returning after a very cold August. Then there was a spell of fine cold weather, with the seven-day mean falling back to 12°, another much warmer fine spell at 18°, and a third at normal temperature (16°).
Between the fine spells there were seven rain days, including very good falls of 19.8 mm on the 1st and 19.0 mm on the 23rd. The total was 66.2 mm.
Despite all the changes, temperatures were not extreme. Only the wet, overcast day on the 6th, reaching 14.3°, was 8° below normal. The hottest day, the 20th, reached 31.5°. Mild frosts on the 10th and 11th did not fall below zero in the screen.
Having twelve mornings completely free of cloud is normal for September. (In 2003, the number was 23!) A milky haze persisted from the 16th to the 22nd, perhaps caused by cypress-pine pollen.

 Comparing September months

The mean of the daily mean temperatures was normal. The mean of the daily maxima was down, and that of the daily minima was up. This made the mean daily temperature range (15.0°) equal lowest September value of the decade, well below the average of 16.5°.
The humidity (early morning dew point: 5.6°) and percentage of cloudy mornings (30%) were a little higher than usual.
The rainfall total, 66 mm, is on the 82nd percentile for September. This is far above the average (41 mm), but less than the 100 mm of September 2005. Last September, by contrast, had only 2 mm: the third driest on record.
Totals for several months together now show no serious shortages. The total for 2 months (August and September) is in the 52nd percentile, 3 months in the 41st, 4 months in the 47th, 5 months in the 32nd, and 6 months in the 22nd percentile. Rainfall totals for longer periods are normal.

Data. Rainfall data is from Manilla Post Office, courtesy of Phil Pinch. Dew point values before August 2005 are from Tamworth Airport 6 am data supplied by the Bureau of Meteorology. Temperature and other data are from 3 Monash Street, Manilla.