Sydney has endured its coldest start to July in 15 years. The first six days of July have failed to reach 17 degrees in Sydney for the first time since 1997. The nippy start to the coldest month of the year was the result of a large and semi stationary high pressure system over southern Australia. This high maintained a persistent flow of cool air from the Southern Ocean into eastern NSW. Yesterday was the coldest day of the month so far reaching just 14.9 degrees, one below the monthly average. Despite plenty of sunny breaks today, the temperature only reached 16 degrees. As the centre of the high moves further east across Victoria tomorrow, the cool airflow will be cut off and Sydney should reach 17 degrees for the first time this month. If Sydney fails to reach 17 degrees once again on Saturday, it will become the coldest first seven days of July in 27 years. In 1985, Sydney remained below 17 degrees for the first 11 days of the month.