Clear skies and light winds caused Adelaide's minimum temperature to dip as low as ten degrees this morning, which is six below average for December. Cool and crisp air in the wake of a cold front helped the mercury dip, reaching temperatures more commonly found in September. In general, it has been a cool start to summer in the South Australian capital, with the average daytime maximum over the past five days just 21.8 degrees, each day staying below 24 degrees. The long term average for December is 27 degrees. Today, plenty of sunshine and warm northerly winds will help boost the mercury into the low 30s for the first time this summer. Tomorrow will also be warm as northerly winds strengthen and transporting interior heat towards the coast. Tomorrow will reach the mid-to-high 30s followed by a warm night in the low 20s, before a cooler change arrives on Saturday.