Thirty years ago, statistical study of aircraft lightning strikes and thunder days at Komatsu airport in winter until 1990 were presented. After that, such study has not been examined. In this study, characteristics of aircraft lightning strikes and thunder days after 1990 are presented. Thunder days at Komatsu airport had increased year by year after 1970 while they had decreased for the last decade (after 2010). The remarkable decrease of thunder days after 2010 and increase of those before 2010 may indicate an existence of long term variation in relation to climate change. A trend of aircraft lightning strikes at Komatsu airport was similar to that of thunder days. There was the largest peak of aircraft lightning strikes in 2010 and, in the same year, there was also a peak in the thunder days. Seventy five percent of aircraft lightning strikes occurred in cloud flight. Forty five percent of aircraft lightning strikes in cloud happened in descending flight. Most (approximately 90) of aircraft lightning strikes in cloud occurred at an altitude below 2000 m. The peak altitude range of aircraft lightning strikes was between 500 and 1000 m. The peak altitude range may be corresponded to cloud base in winter. The most dangerous flight condition was descending flight in cloud at an altitude between 500 and 1000 m.
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