The best months for Wadi Rum are March to May and September to November. Spring brings wildflowers to the canyon floors and comfortable daytime temperatures around 25-30°C. Autumn is similarly pleasant, with the bonus of reliably clear skies.
Summer is brutal. Temperatures regularly exceed 40°C, the sand burns through your shoes, and even short walks become exhausting. If you must visit in July or August, stick to early morning and late afternoon, and drink far more water than you think you need.
Winter brings cold nights — genuinely cold, sometimes below freezing — and the contrast with mild daytime temperatures catches people off guard. Bring warm layers for evenings at the camp. The upside is that winter light is spectacular, the desert is empty of crowds, and the air is so clear you can see Saudi Arabia from the high ground.
Ramadan affects tour availability and camp meal schedules. Plan ahead if your visit falls during the holy month.