METRO (Meteorology) – VT-10 Primary Practice Test

The main idea here is that these weather categories are the FAA’s standard way to summarize ceiling and visibility for flight operations, and the official definitions come from the FAA’s Flight Information Handbook. Specifically, in the Flight Information Handbook under the National Weather Service – FAA Weather Information Service section, you’ll find the exact thresholds used to define LIFR, IFR, MVFR, and VFR. Those thresholds are what pilots rely on when interpreting weather data from METARs and TAFs.

For reference, the commonly used ranges are: LIFR means ceilings below 500 ft and/or visibility below 1 mile; IFR means ceilings 500–999 ft and/or visibility 1–2.9 miles; MVFR means ceilings 1,000–3,000 ft and/or visibility 3–4.9 miles; VFR means ceilings at or above 3,000 ft and visibility 5 miles or more.

While the AIM covers weather topics and procedures, and the METAR Glossary explains terms used in reports, the official category definitions are published in the Flight Information Handbook. The FAA Weather Camera Portal isn’t relevant to these definitions.