Melbourne's warm spell came to an abrupt end this afternoon as a southerly change swept through the city, with peakhour storms adding to the turbulent weather. The cool change ended a three day warm spell where maximum temperatures in Melbourne reached 31 to 33 degrees, which is nine to 12 above average for this time of year. The mercury plunged by five degrees in 10 minutes when the southerly arrived today and will drop even further as showers and storms affect the city tonight. The evening's first storm formed near Seymour before moving south into eastern suburbs of Melbourne at around 5pm, just in time for the evening peak hour. Showers are likely to continue in Melbourne tonight and on Thursday and further storms are also possible. A severe weather warning has also been issued for all of western and parts of central Victoria due to heavy rain, which may cause flash flooding tonight and on Thursday.