Heavy November rainfall

November’s heavy rainfall was in complete contrast to the preceding ten months when low falls prevailed. Despite the high falls, the spring total was still below average.

With all ten months to the end of October receiving well-below-average rainfall – six of them recording less than half their average – November’s rainfall average was more-than tripled.

After heavy overnight rainfall, there was 39.6mm in the gauge at the airport’s automatic weather station on the morning of November 6 – the second-highest single-day total for November to the record 87.2mm that fell on November 4, 2015.   

The month’s total of 76.4mm on 12 days, compared with the average 24.4mm on five days, was the highest since a record 97.6mm fell on six days - also during November 2015.

Rainfall to the end of November is 203.0mm on 66 days compared with the average 325.0mm on 75 days.

Due to the heavy November falls, the progressive rainfall total has gone from second-driest at the end of October, to eleventh driest at the end of November.

Daytime temperatures during November averaged 26.3C - 1.5C below the norm – and were the coolest since 2001 when the average was 25.6C.

November nights averaged 13.1C – 0.5C above the norm.  

The average daytime temperature for November of 27.8C is 3.2C warmer than October’s average, but for only the fifth time in 97 years of record, October’s days were warmer than those of November. The last time that this happened was during 1999.

Another anomaly was that the last 11 days of November – usually the warmest part of the month – averaged only 22.2C – a huge 5.6C below-average.      

Spring was a lop-sided affair as far as rainfall was concerned, with September and October contributing only 7.2mm, on seven days, to the 83.6mm total that fell on 19 days.

The spring average is 92.2mm on 20 days.   

The average daytime temperature during spring was 24.8C – just 0.2C warmer than usual – while nights averaged 10.1C – 0.3C below average.

Daytime temperatures ranged from 38.6C on October 31, to 15.5C on September 15, while nights had a top of 23.9C on November 2, to a low of 0.0C on September 4.

During spring only 15 days exceeded 30C compared with the average 23 days. Four of those days went on to pass 35C – four less than average – while two exceeded the old 100F (37.8C) mark – one less than average.

Joe McLaughlin compiled the statistics from data supplied by the Port Pirie airport’s automatic weather station and the Bureau of Meteorology in Adelaide.