Smog and Air Traffic in Pakistan

Smog is a mixture of smoke, dust and pollution that hangs in the air and reduces visibility. In parts of Pakistan, notably around Lahore, it can build in autumn and winter, especially when winds are light, and can delay flights.

How smog affects flights

Smog reduces horizontal visibility near the ground, much like fog. If visibility falls below limits for landing or takeoff, flights are delayed or diverted. In a METAR, smoke is coded FU and haze HZ. See how to read a METAR.

Smog and fog together

In winter, smog and fog can combine into a persistent low-visibility layer, particularly on the northern plains. See fog and flight delays.

When it is worst

Light winds and cool, still air trap pollution near the ground, most often from roughly October to January. Rain and stronger winds clear it.

What passengers can do

• Check live weather before leaving: Lahore weather.
• Allow for delays, particularly early morning.
• Wear a mask if outdoors in heavy smog; the same advice as for health.

See also visibility and common causes of delays.

General information only, not legal or safety advice. Details change; check with your airline and the relevant authority. See our editorial policy.