The strongest hazards may be hidden inside cloud
Pilots cannot judge a storm reliably by appearance alone, especially at night or when layers obscure it. Weather radar provides a picture of precipitation intensity and helps identify areas to avoid.
Heavy rain can mask what lies behind it
Radar energy can be absorbed by intense precipitation, creating attenuation. Crews learn to recognize suspicious shadows and avoid assuming that a dark area behind a strong return is clear.
Hail can occur outside the visible core
Strong updrafts can carry hailstones away from the most obvious rain shaft. That is one reason aircraft maintain lateral distance rather than merely skirting the edge of a bright radar return.
Wind shear is especially dangerous near the ground
A storm can produce rapid changes in wind speed and direction during takeoff or landing. Airports and aircraft may provide alerts, and crews can delay, go around or choose another runway.
Route changes are normal in convective weather
Air traffic control may establish broad deviations or close portions of airspace. Flights can take longer routes because safe separation from storms is more important than the published airway.
Avoidance margins depend on the situation
Storm motion, altitude, terrain, radar quality and surrounding traffic all matter. Airline procedures provide minimum guidance, while crews use judgment to create additional space when conditions warrant it.
A thunderstorm contains several hazards at once
Severe turbulence, hail, lightning, heavy precipitation, icing and rapid wind changes can all exist within or near one cell.
Radar shows precipitation, not every hazard directly
Strong returns help crews identify dangerous convective areas, but attenuation and geometry can hide conditions behind intense cells.
Distance is safer than threading between strong cells
Crews and dispatchers plan meaningful lateral avoidance because conditions can extend beyond the visible cloud boundary.
Takeoff and landing add wind-shear risk
Microbursts and gust fronts can rapidly change airspeed close to the ground, where there is little altitude available for recovery.
Storm systems can disrupt an entire network
Airways may close, arrival rates fall and aircraft may need large deviations, creating delays far from the actual storm.
Night can make visual avoidance harder
Lightning illuminates cloud but does not provide a reliable picture of cell structure. Crews depend heavily on radar and weather information.
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