In this month, the weather is generally nice, with bright days and still cool or chilly nights. However, at this time of the year there may be intermittent inflows of chilly air due to the flow of southern winds. They are usually followed by a cold dry wind from the southwest called Pampero, as it comes from the Argentine Pampa.  Sometimes, these cold winds settle to the north of Río de la Plata, thus resulting in low pressure systems which usually cause heavy rains for several days, overcast skies, and strong southeast winds (sudestada) over the city.

In Buenos Aires, the mean temperature during this month is approximately 17°C (62.6° F), the mean maximum temperature is 22°C (71.6° F), and the mean minimum temperature is 13°C (55.4° F). As to extreme values, the maximum may occasionally be over 32°C (89.6° F) and the minimum may rarely go below 0°C (32° F).

In connection with rainfall, the monthly mean is 119.0 mm, distributed over 10 days a month, on average. Relative humidity is 70%, approximately. From this month on, it begins to go down, just like the mean frequency of foggy days, which is 0.3 days. The mean for stormy days is 5 days, on average. This frequency increases by mid spring.

As to clouds, October features 10 days with clear sky and 8 days with an overcast sky, on average.
The mean frequency of strong winds (equal or higher than 43 km/h) is 4 days a month. The maximum wind speed may be over 150 km/h, as it happened in October, 1993, when winds of 157 km/h blew over the city.