In-flight Weather Information

Many times, pilots choose to take off and evaluate the weather as they go.  At typical GA aircraft speeds, a 200-mile trip can leave a 2-3 hour weather information gap between the preflight briefing and the actual flight. In-flight updates are vital!  Sources:

Visual Updates: Use your eyes to survey the weather and literally see whether conditions match what was reported or forecast. Sometimes there are local deviations in weather conditions (isolated cells, fog, etc.) that may not be immediately known to the FSS specialist or that may not appear on weather-product depictions.

ATIS/ASOS/AWOS: Listen to ATIS and ASOS/AWOS broadcasts along your route. These broadcasts can help you update and validate preflight weather information about conditions along your route of flight.

Enroute Flight Advisory Service (EFAS, or Flight Watch): Available on 122.0 in the continental United States from 5,000 AGL to 17,500 MSL, Flight Watch provides en route aircraft with weather advisories pertinent to the route of flight and altitude. Provide aircraft identification and the name of the VOR nearest to your position.

Air Traffic Control (ATC):  Monitoring ATC frequencies along the way is one way to keep abreast of changing weather conditions.   You can also request information on the present location of weather, which the controller will try to provide if workload permits.

Datalink and Weather Avoidance Equipment: Radar and lightning detectors can contribute significantly to in-flight weather awareness.  An increasing number of GA aircraft are now being equipped with weather datalink equipment, which uses satellites to transmit weather data such as METARs, TAFs, and NEXRAD radar to the cockpit. Handheld devices with weather datalink capability are also popular.

One of the most important, and critical, things to know about datalink is that regardless of the transmission method, it does not provide “real-time” information.