Aviation Weather Information Flashcards
7 cards from real SPC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Aviation Weather Information flashcards as text
Which type of fog forms when warm, moist air moves over a cooler surface?
Answer: Advection fog
Advection fog forms when warm moist air moves horizontally over a cooler surface, cooling the air to its dew point — common along coastlines and in spring over cold land.
What weather phenomenon is most likely when the temperature and dew point spread is 5°F or less and is decreasing?
Answer: Fog or low cloud formation
A small and decreasing temperature-dew point spread indicates the air is approaching saturation, making fog or low cloud formation likely.
Mountain wave turbulence is most likely to occur when winds at mountaintop level are:
Answer: At least 25 knots and perpendicular to the ridge
Mountain wave turbulence is most severe when surface winds are at least 25 knots and blow nearly perpendicular (within 30°) to the ridge line.
What is a lenticular cloud, and what does its presence indicate to a pilot?
Answer: A lens-shaped cloud forming in the crest of a mountain wave indicating turbulence
Lenticular (lens-shaped) clouds form at the crest of mountain waves and are a visual signal of potentially severe turbulence and strong up/downdrafts in the area.
What ceiling and visibility values define Instrument Meteorological Conditions (IMC)?
Answer: Ceiling below 1,000 feet AGL and/or visibility less than 3 miles
IMC exists when the ceiling is below 1,000 feet AGL and/or visibility is less than 3 miles, requiring instrument flight rules for flight.
An area forecast (FA) covers weather conditions for an area how large?
Answer: A region covering several states
Area Forecasts (FA) cover large geographic regions encompassing several states, providing general aviation weather information including clouds, visibility, and hazards.
The tropopause is significant to pilots primarily because:
Answer: Jet stream winds are strongest near the tropopause and it acts as a temperature inversion limiting convection
The tropopause is the boundary between the troposphere and stratosphere where temperature stops decreasing; jet stream winds concentrate near it and it caps convective activity.