Trends in Instrument Flight Rules (IFR) Conditions at Major Airports in the United States

Abstract

AbstractWeather-related delays are among the most common in aviation and are frequently the result of low visibility or cloud ceilings, which cause landing aircraft to be spaced farther apart for safety, reducing the capacity of an airport to land aircraft in a timely fashion. Using 45 years of archived surface observations from 30 of the busiest airports across the United States, the prevalence of low-visibility and low-ceiling conditions is examined, along with the meteorological conditions that support them and the associated trends over time. It is shown that these conditions are becoming less frequent at most locations?for many significantly so?and that this decrease can be seen at all times of day and in all seasons.