Description of the weather for Friday 6 October 1848 when Agincourt arrived in Sydney
It was a cold day at the signal station on South Head. The maximum temperature was reported in the low 50s Fahrenheit - about 10 to 11 degrees Celsius.
The Sydney Morning Herald, Wednesday 11 October 1848, p2, Meteorology
Friday 6 - Very cold and frosty early noon, with fog till about seven o'clock; moderately fresh westerly breezes forenoon; snowy fleecy clouds floating in a deep blue sky; about twelve o'clock began to blow exceedingly cold from southward, with some rain, (which at a few miles to westward of this was accompanied by small hail); atmosphere remained intensely cold and raw, (most remarkably so for the season), all the rest of the day; two to three P.M. some some squalls of wind and rain; afterward fair and sunshine; during the evening stormy nimbus hanging in the eastern sky, and occasional lightning; all latter part of the night rainy, and a coarse boisterous wind from south-south-west.