, the hottest temperature ever recorded for the city and humidity levels dropped to as low as two percent. The McArthur Forest Fire Danger Index reached unprecedented levels, ranging from 160 to over 200. This was higher than the fire weather conditions experienced on Black Friday in 1939 and Ash Wednesday in 1983. Around midday, as wind speeds were reaching their peak, an incorrectly-rigged 'SWER' (single-wire earth return) mains power cable was ripped down at Kilmore East. This sparked a bushfire that became the deadliest and most intense firestorm ever recorded in Australia. The overwhelming majority of fire activity occurred between the afternoon of 7 February and 7:00 pm, a period when wind speed and temperature were at their highest, and humidity at its lowest. Chronology Wednesday, 28 January 2009 Delburn fire commenced in Central Gippsland; arson suspected. Wednesday, 4 February Bunyip State Park blaze commenced. Saturday, 7 February (Black Saturday) 05:00 am – Bunyip State Park fire jumped containment lines; no other major fire activity. Late morning – Many fires sprang up as temperatures rose and wind speeds increased. 11:50 am – Power lines fell in high winds igniting the Kilmore East fire (Kinglake/Whittlesea area). The fire was fanned by winds, entered a pine plantation, grew in intensity, and rapidly headed southeast through the Wandong area. 12:30 pm – Horsham fire commenced. 12:30 pm – ABC Local Radio abandoned regular programming to cover the fire situation. 12:45 pm – Hume Freeway was closed after fire crews were unable to contain Kilmore East fire. Early afternoon – ABC Local Radio received calls from residents of affected areas supplying immediate up-to-date information on fire activity. 2:55 pm – Murrindindi Mill fire (Marysville area) first spotted from Mt Despair fire tower. 3:04 pm – temperature in Melbourne peaked at . 4:20 pm – Kilmore East fire front arrived at Strathewen. 4:20 pm – Murrindindi Mill fire impacted Narbethong. Mid-afternoon – smoke from Kilmore East firestorm prevented planes from mapping the fire edge. 4:30 pm – number of individual fires across the state increased into the hundreds. 4:30 pm – fire commenced at Eaglehawk, near Bendigo. 4:45 pm – Kilmore East fire front arrived at Kinglake. 5:00 pm – wind direction changed from northwesterly to southwesterly in Melbourne (see Fawkner Beacon Wind chart for 7 February 2009). 5:10 pm – air temperature in Melbourne dropped from over to around in fifteen minutes. 5:30