Key Summary- The vast majority of Iraq falls under a hot desert climate (BWh), with extremely high summer temperatures and minimal rainfall.
- A northern band transitions to a hot semi-arid climate (BSh), receiving slightly more winter precipitation that supports sparse grassland.
- A small pocket of Mediterranean climate (Csa) exists in the northeastern mountains, where altitude brings cooler weather and winter snowfall.
Iraq’s climate is defined by intense summer heat, cool winters, and a stark scarcity of rainfall across most of its territory. The accompanying Köppen climate map immediately reveals the overwhelming dominance of the hot desert classification BWh, which stretches from the alluvial plains of the Tigris and Euphrates south to the Persian Gulf and west across the rocky Syrian Desert. This is a region of fierce continental extremes, set well away from moderating ocean influences other than the narrow, shallow Gulf coastline. In our WeatherBox charts, you will see summer high temperatures routinely climbing to 45°C to 50°C (113°F to 122°F), while winter nights in the western desert can dip close to freezing. Annual precipitation throughout this zone rarely tops 150 millimetres (6 inches) and falls almost entirely between November and April, often in short-lived but intense showers. The northern plains, including Mosul and Kirkuk, ease into a hot semi-arid BSh zone, where a more pronounced winter wet season pushes yearly rainfall to roughly 250 to 400 millimetres (10 to 16 inches). In the extreme northeast, the Zagros Mountains capture enough winter moisture and altitude-driven cold to qualify as a small Mediterranean climate Csa, the only part of Iraq where regular snowfall and forested slopes occur.
Geography dictates this dramatic climatic gradient. The low latitude, between roughly 29°N and 37°N, results in stubbornly high insolation, while the great landmass of Arabia reinforces the dry, sinking air that suppresses cloud formation for months. The narrow strip of coast along the Gulf does little to cool the south but adds an oppressive layer of high humidity to the blistering heat, making Basra’s summer among the most uncomfortable on Earth. In winter, mid-latitude storm tracks occasionally sweep in from the Mediterranean, delivering most of the country’s precious rain. The mountains of the northeast intercept these systems, creating a modest rain shadow that further starves the lowlands of moisture. This seasonal rhythm leaves a brief, pleasant spring when the northern steppe briefly turns green, a long summer dominated by cloudless skies and the dusty shamal wind, and a short autumn that quickly gives way to chillier conditions. By the time you examine our detailed WeatherBox data, you will notice this pattern repeats with remarkable consistency, carving out one of the most arid and sun-drenched environments on the planet.
