Many Adelaideans had sleeping difficulties last night with the temperature hovering in the 30s almost all night, the hottest night in three years. The temperature was still 33.4 degrees at midnight and stayed above 30 before only briefly dipping below 30 at about 4:30am. If anyone had intentions of sleeping in, to make up for a late New Years Eve, they may have had some difficulty. The temperature rose to 35 degrees at 9am. The overnight minimum of 29.2 degrees made it the highest minimum temperature since January 2009, when the overnight low was 33.9 degrees. Effectively, it was the hottest night in three years. Today is heating up steadily as northerly winds develop, with the city reaching 37 degrees at 10am and heading for 40 degrees, which is 11 above the January average. At 10am, both Parafield and Elizabeth had reached 38 degrees and Roseworthy 39, well on the way to 40. If Adelaide hits 40 it will be the second 40-degree day in a row. Yesterday peaked at 41.6 degrees, late in the afternoon, making it the hottest New Years Day in 112 years. Tonight should not be as warm as last night but there will be a bit more humidity, due to a weak southwesterly change arriving later today. Tomorrow will heat up to the mid 30s again before a stronger cooler change arrives late in the day. From Wednesday, the city and much of SA will have cooled by 10 to 15 degrees.