In the coming weeks, pilots can expect to see mountain waves in several snowy, mountainous regions. When wind flow is perpendicular to a mountain, as the wind velocity and altitude increase during an inversion below 15,000 feet, or a stable air mass layer aloft, mountain waves will occur. These atmospheric disturbances are characterized by lenticular clouds that alert pilots to their potentially deadly presence. It’s possible to predict mountain waves and other atmospheric disturbances with a high level of accuracy, though, giving pilots a chance to decide whether or not to fly under such conditions.
How to Check for Weather Conditions Before and During Your Flight
There are a couple of ways to check the weather for disturbances such as mountain waves before you fly, mainly through observations and weather forecasts. There are also online weather resources, including the Aviation Weather Center and DUATS.
• Metar – Airman’s meteorological reports
• Radar Summary Charts – Reports showing analyses of precipitation surface with cold fronts, warm fronts and areas of high or low pressure
• Surface Analysis Reports – Focus on areas of high or low pressure, as well as cold or warm fronts
• U.A. – Real-time reports from fellow pilots (recommended)
• 12/24-Hour Prognostic Reports – Show where cold fronts, warm fronts and areas of high or low pressure are going to move
• F.A. – Explains reasons for weather forecasts in different areas
• TAF’s Terminal Aerodrome Report – Provides expected future weather for area surrounding airports (not available for all airports)
Deciding Whether or Not to Fly – Know Before You Go
In addition to mountains waves, thunderstorms are also a serious danger to pilots during this time of year. You should always be ready to change your plans or land if you’re presented with scattered storms, as the pilot did on a recent SR22 flight from San Diego, CA to Sarasota, FL, which is pictured below.
The pilot used an Avidyne radio and XM Satellite Weather to predict the weather and made the important decision to land. In order to make a proper go/no go decision, it is necessary to understand the weather and where and how it is generated, so you can effectively predict whether atmospheric changes are likely to occur in the areas where you will be flying. Pilots who are proficient at flying in different environments may also be able to take more risks, whereas inexperienced pilots are in greater danger when flying into mountain waves and other atmospheric disruptions. Pilots should always look at weather observations and forecasts before flying, recognize their personal limits and the limits of their plane, and be ready to make adjustments during the flight if necessary.