Extracted only airports where FZ has been registered during the three-year time period.
FZ is flagged as TRUE/FALSE
Timestamp duplicates have been dealt with and kept in prioritized metartype-order: ['SPECI', 'COR', 'MANUAL', 'AUTO']
Before cleaning: 3275713 rows
After cleaning: 1610629
Ended up with 74 airports in total.
Have done some basic plotting to look at the distribution and simple statistics.
METAR-data is more or less ready.
Overview:
Have done some basic plotting to look at the distribution and simple statistics.
Heatmap of FZ occurrences: