Afghanistan's mostly mountainous geography makes for varying degrees of harshness depending on the altitude. Most of the country experiences a severe winter from December to February where 8°C (47°F) is a warm day and -8°C (18°F) a very cold night. A light to moderate wet season occurs from October to May with March and April being the only particularly wet months. Between June and September it is quite dry with average highs of 30-32°C (86-89°F) and apart from the arid winds along the Iranian border it can be quite pleasant. However May and September to October provide particularly comfortable mid-20°C (around 80°F) days and a little more moisture. Afghanistan's lower areas have slightly warmer winters with the only significant rain for the year and summer days bake with an average high around 39°C (104°F) in July.