Weather will likely play an important role when you plan your trip to Siwa, but bear in mind that cheaper options are usually available when the weather isn’t as good. The hottest months are usually July and August, with an average temperature of 30°C, while the coldest months are January and February, with an average of 15°C. Between January and March, the daytime average is 24°C and the night-time average is 9°C. Between April and June, temperatures average 37°C during the day and 16°C at night. Between July and September, the temperature averages 38°C during the day and 22°C at night. Between October and December, the average temperature is 30°C during the day and 10°C at night.