October 2013 Review - Sydney

Sydney saw very warm maximums for most of the month of October. There were 7 days above 30C, with a monthly maximum of 37.8C recorded on October 10. This was the 4th warmest October day since 1939. The highest monthly minimum of 20.2C recorded on October 23 was the warmest in the last 5 years and within the top 90th percentile for records since 1939. Bushfires affected areas around Sydney for more than a week in the middle of the month on the back of these warm temperatures.

The table below compares averages from the last 5 years for the month of October at Sydney Airport.

Sydney	2009	2010	2011	2012	2013
Average Min.	14.0	14.7	14.2	13.5	14.4
Average Max.	21.9	22.5	22.1	23.8	26.2

Monthly averages for October at Sydney Airport for the period 2009-2013

Of the last 5 years this October was easily the warmest in terms of daily maximums. In fact, looking at Bureau of Meteorology records, this October was actually the second warmest since 1939. Only 1988 was warmer with an average maximum of 27.0C. It's also worth pointing out that only 2007 besides 1988 and 2013 had an average maximum above 25C. 

Another interesting observation is that the average maximum was actually 27.2C with 8 days remaining in the month. If not for the cooler final 8 days of October, which had an average maximum of 23.3C, the record would have been broken. 

Minimums, on the other hand, were fairly normal compared to the previous 5 years. A steady increase of average minimums since 1939 means 2013's average was above the overall average of 13.2C. The lowest overall temperature of the month, 9.7C on October 17, was similar to previous years, while the lowest maximum of 17.7C on October 16 was the warmest in the last 5 years.

As I mentioned in a recent post, the highest wind gust in more than a year was also experienced, 95km/h on October 29. In terms of rain, the monthly total of 16.2mm was well below the long term average of 70.1mm.