January 2015 Review - Sydney

It was a very warm January at Sydney Airport in 2015. With a week remaining in the month, the Airport was on track to record the highest average minimum on record. A drop in temperatures, however, which included the coldest January day since 2000, led to the final recording being the seventh warmest on record according to Bureau of Meteorology accounts.

The cooler period also led to the average maximum missing a potential record. In the end it was the fifth highest in the Airport's 76 years of January records. These figures were obviously well above the average and rainfall was also above average.

Averages from Januaries between 2009 and 2015 are shown below alongside the long term figure.

January averages at Sydney Airport for the period 2009-2015 plus the long term average

January 14 recorded the highest temperature of the month when it reached 36.7C. Only 2011 and 2012 recorded lower figures since 2009. 2009, 2010 and 2013 all recorded a hottest temperature above 40C. The highest minimum of 23.4C came on the 23rd, just before a drop in temperatures a couple of days later.

The 27th day of the month wasn't warmer than 20.6C. This was the lowest daily maximum for a January day since 2000. The lowest overall temperature was also a little unusual. It dropped to 14.3C on the 30th. In the past 30 years, there have been only seven January minimums lower than that.

The warm average of the month was helped by the number of days above 30C. There were 11 in total, three of which also exceeded 35C. 2009 and 2013 saw 13 and 12 days above 30C. There were also 20 minimums above 20C, 11 of which were the first 11 days of the year. Not once in the Airport's history had it not dropped below 20C by January 11 until this year. The last six days of the month, however, failed to hold above 19C, leaving 2011 and 2013 to remain with higher figures of 23 and 22 minimums above 20C respectively.

Daily minimums and maximums against rainfall at Sydney Airport for January 2015

January rainfall was much higher for Sydney in 2015 compared to 2014. The Airport received 112.6mm during the calendar month, comfortably above the long term average of 93.9mm. The Bureau recorded 112.8mm (0.2mm from December 31). Since 2000, 2015 was the fourth January to exceed 100mm of rain. In 2014 the Airport saw only 11.2mm.

The month saw 14 days of rain. A eight day dry streak ran from the first day of the month until the 8th, but it was followed the longest run of rain days, six from the 9th until the 14th. January 27 recorded the highest daily total with 35.0mm. The 28th, which saw 23.8mm, and the 11th with 16.8mm, were the only other days to record more than 15mm.

Wind strength wasn't especially high during the month. The highest gust of 69km/h was seen on both January 8, a north-northeasterly, and on the 25th, a southerly. May last year was the last month to record a weaker strongest gust. January in 2013 and 2014 recorded higher gusts also. The calmest day was the last day of the month. The strongest gust then was only 31km/h.