I've spent the last few weeks analysing the daily highs and lows of other pairs, and made an interesting observation. The 'midnight hour', or the first hour of the day, tends to contain the day's high or low.
The following charts the distribution of the daily highs and lows for the USDJPY, AUDUSD, EURJPY, EURAUD, AUDNZD and EURUSD. I primarily focused on AUD and JPY pairs, being based in Australia.
If you look at the charts below, the midnight hour features prominently.
This observation seems to hold true with the EURUSD, a non-Asian pair, although it isn't the most prominent in this case.
My guess is that during a strongly-trending market, it's possible for price to move in one direction for the entire day, hence the prominence of daily highs and lows during the first hour. If you're daytrading an Asian pair, the high or low of the first hour looks like a good place to put your stop loss.