Japanese monetary policy and its impact on stock market implied volatility during pleasant and unpleasant weather*

We investigate the effect of Japan's Monetary Policy Meeting releases on the intraday dynamics of the Nikkei Stock Average Volatility Index and its futures during pleasant and unpleasant weather. We show that at the time of a monetary policy release when the temperature is pleasant, there is a significant decline in Japanese equities' implied volatility and futures, which lasts for about 10 min and 5 min, respectively. This decline is longer and exhibits a greater variation when releases occur during cold days. Finally, we emphasize the achievable economic profits and losses, given the reaction of Nikkei VI futures to the Japanese monetary policy releases during pleasant and unpleasant weather days, respectively. In particular, taking a short position at the start of the trading day on pleasant days and closing this position at the end of the trading day generates an average annual return of 5.6%.

Automated summary

The study examines how Japan's Monetary Policy Meeting releases affect the intraday dynamics of the Nikkei Stock Average Volatility Index and its futures in different weather conditions. It shows that Japanese equities' implied volatility and futures decline significantly when the temperature is pleasant during the release, with the decline lasting longer and exhibiting greater variation on cold days. Additionally, the study highlights the economic profits and losses that can be achieved by trading Nikkei VI futures based on the reaction to Japanese monetary policy releases during pleasant and unpleasant weather days.