Today (22 July 2026), Greece is experiencing a dangerous weather phenomenon known locally as libas — a powerful foehn-type wind that is intensifying heat, drying out vegetation, and dramatically raising the risk of wildfires. Meteorologist Theodoros Kolydas explains the science behind this event in a detailed analysis.
How the Libas Forms
The libas develops when a strong westerly wind encounters the Pindus mountain range. As the air rises on the western (windward) side, it expands and cools. If it reaches saturation, clouds form and precipitation may occur — causing the air to lose much of its moisture.
From Cooling to Scorching Heat
Once the air mass crosses the mountain crest and begins descending on the eastern (leeward) side — over regions like Thessaly — the process reverses. The air compresses and warms at the dry adiabatic lapse rate: roughly 1°C for every 100 metres of descent. Having already shed most of its humidity, the air arrives at lower elevations significantly warmer and drier.
Extreme Temperature Jumps
This mechanism can trigger dramatic temperature surges — up to 20°C during descent. In today’s event, peak temperatures are expected to reach 43°C in the Thessalian plain — up to 8°C higher than in western Greece at the same time.
Wind Intensification Adds Danger
As the air accelerates down the leeward slopes — aided by channeling through valleys and mountain passes — the libas often becomes gusty and turbulent. This creates a volatile combination: soaring temperatures, plummeting humidity, and strengthening winds — a perfect setup for rapid fire ignition and spread.
Kolydas notes that this foehn effect is a key topic in his postgraduate meteorology lectures at the Democritus University of Thrace, where it is studied alongside other atmospheric processes linked to natural disasters. Its ability to transform local weather conditions — temperature, moisture, and wind intensity — within hours makes it one of the most impactful and hazardous regional weather phenomena in Greece.