average temp st petersburg florida for october
St Petersburg: Annual Weather Averages. July is the hottest month in St Petersburg with an average temperature of 18Â°C (64Â°F) and the coldest is January at -6Â°C (22Â°F) with the most daily sunshine hours at 9 in July. The wettest month is October with an average of 100mm of rain. The best month to swim in the sea is in July when the average sea temperature is 19Â°C (66Â°F).