A Skew-T diagram shows how temperature and moisture change with altitude through the atmosphere. It's the same type of chart used by meteorologists and pilots.

The Lines

• Red line = Temperature at each altitude
• Green line = Dew point (how moist the air is)
• Blue dashed line = Freezing level (0°C)

What to Look For

• Blue shading between the lines = near-saturation (T–Td < 3°C) — cloud or fog forming at that level
• Lines far apart = dry air — clear skies at that level
• Orange shading = temperature inversion — a warm lid trapping air below. When annotated as "Cloud INV", there's also moisture trapped below (the cloud sea effect), with estimated cloud base and top heights shown
• Temperature going right (warmer) as you go up = inversion layer
• Wind colour: green = calm (≤3 mph), yellow = moderate, red = strong (>11 mph) — calm winds favour inversions

Cloud Inversions

The classic "above the clouds" mountain experience happens when:

• There's a temperature inversion at 400–1500m altitude
• Air is moist below the inversion (red & green lines close) — cloud trapped there
• Air is dry above the inversion (lines spread apart) — clear summit views
• Winds are light (not mixing everything up)

The Numbers

• Left axis = pressure in hPa (higher = lower altitude) with approximate height
• Bottom axis = temperature in °C (skewed to the right)
• Right column = wind direction and speed at each level

Data is from the UKMO (Met Office) forecast model via Open-Meteo. Use the time slider to see how conditions evolve.