There are two primary types of mountain waves: trapped lee waves, and vertically propagating waves. In this article, we'll focus on trapped lee waves, and the types of turbulence you can expect flying through them.
An Aviation Selected Special Weather Report (SPECI) is an unscheduled report taken when there is a significant change in the weather during the period between the hourly reports. SPECIs contain all data elements found in a METAR, plus additional plain language information which elaborates on data in the body of the report.
You're about to depart an airport under IFR with low ceilings. There's no SID and no ODP. When can you start your on-course turn, and why? It's called a "diverse departure assessment", and here's how it works.
If you fly over mountainous or rough terrain you'll see cumulus clouds and thunderstorms popping up in the same place day after day, on top of the ridgeline. Why is this?
If you can't safely maintain the required climb gradient for an instrument departure, a VCOA might be a great option. Here's what you need to know before you fly one under IFR.