Ethiopia is pretty pleasant all year round, with temperatures in Addis Ababa averaging around 20°C (68°F) no matter what the season. Early October, just after the rains is a particularly good time to visit. The country is wonderfully green, the wildflowers are stunning and there are fewer visitors. Trekking during this time is especially sublime, though it’s pretty amazing throughout the entire dry season (October through mid-March).
The rainy season in most of the country is from mid-June to the end of September. If you’re planning to visit the Lower Omo Valley, avoid April, May and October, when rains are heaviest and roads are impassable. Finally, you’d do well to coincide with one of Ethiopia’s very colorful festivals, particularly Timkat or Meskel. Be aware, however, that domestic flights and hotels often fill up far in advance of Ethiopian festivals and European Christmas.
Floods – Capital Tensions – Border Issues
Heavy rains have lead to flooding in parts of the country, mostly in the northwest (Tigray, Amhara and Afar) and southwest. Travelers should seek local advice on road and transport conditions.
Political violence flares up now and then in Addis Ababa. Travelers should monitor local news and stay clear of any mass demonstrations.
Travel to the Eritrean border military zone – in the Tigray and Afar regions – should be avoided. The border itself is permanently closed. Ethnic tensions dog the west of the country. Borders with Kenya, Somalia and Sudan are also very dangerous with an extreme risk to traveler’s security.
Check out Safe Travel for updated government warnings or the Thorn Tree travel forum for some good advice from travelers.