airports$tz with values \N replaced with NA (#36).
weather$year and weather$month are now integers to match flights$year and flights$month (@jozefhajnala, #34)
weather$time_hour and flights$time_hour are now stored in the America/New_York timezone (#19).
weather data updated from latest Iowa State mesonet (@rmcd1024, #24). wind_gust is now correctly captured from the underlying data, rather than being a copy of wind_speed. precip is better captures the hourly preciptation (which tends to be recorded at 51 minutes past the hour) (#27)
nycflights imports tibble so you get nice printing even when no other tidyverse package is loaded.
airports now has a tzone column that contains the IANA time zone for the airport (#15).
airlines: carrier columns are characters instead of factors (#2).
airports: duplicate entry for BFT removed (#7).
flights:
new time_hour variable combines year, month, day, and hour into a single variable (#11).
new sched_dep_time and sched_arr_time variables give scheduled departure and arrival times - these are more appropriate for connecting to weather data. hour and minute are now computed from the scheduled departure time, not the actual departure time.
missing tailnum now recorded as NA, not "" (#10).
weather:
Includes weather data for all airports.
New time_hour variable combines year, month, day, hour into a single POSIXct variable.
Saved as ungrouped.