The honest answer to when you should fly Philadelphia to Sydney is mostly about weather and demand at the far end. On three years of daily observations at the arrival airport, Apr, Sep-Nov gives the most comfortable combination of temperature and rainfall in Sydney.
Averages below come from three full years of daily readings at Sydney’s main airport, not from a seasonal generalisation. The warmest month is February (average high 27°C), the coolest is June (average low 9°C), and the wettest is May (150 mm).
| Month | Avg high | Avg low | Rainfall | Wet days | Philadelphia high |
|---|---|---|---|---|---|
| January | 26°C | 19°C | 121 mm | 14 | 3°C |
| February | 27°C | 20°C | 74 mm | 13 | 6°C |
| March | 25°C | 19°C | 93 mm | 15 | 14°C |
| April good | 23°C | 15°C | 98 mm | 10 | 19°C |
| May | 20°C | 13°C | 150 mm | 17 | 23°C |
| June | 17°C | 9°C | 66 mm | 8 | 30°C |
| July | 17°C | 9°C | 72 mm | 9 | 31°C |
| August | 19°C | 10°C | 102 mm | 11 | 29°C |
| September good | 23°C | 11°C | 53 mm | 5 | 26°C |
| October good | 24°C | 14°C | 39 mm | 9 | 21°C |
| November good | 25°C | 17°C | 85 mm | 13 | 14°C |
| December | 27°C | 18°C | 69 mm | 9 | 7°C |
Climate data: Open-Meteo reanalysis archive.
Sydney runs 14 hours ahead of Philadelphia. Travelling east is the harder direction to adjust to, so if the trip is short, an early departure that lands in daylight is worth more than a marginally cheaper overnight.
We publish observed fares for this route when we have them, and say nothing when we do not — there is no estimate on this page. What holds regardless of the route:
Midweek departures are consistently cheaper than Friday and Sunday on most routes, because that is where demand sits rather than because of any pricing trick. Where we have observed fares for Philadelphia–Sydney, the weekday breakdown appears further down this page; where we do not, we leave it out rather than estimate it.
Top-rated tours and experiences in Sydney, ranked by traveller rating. Prices are per person and change with date and group size.
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