When one country is on holiday and the rest of the market isn't

[Shadow Trader]

A Japanese holiday, a UK bank holiday, a US Thanksgiving: the market doesn't close, but a chunk of its liquidity does.

On a UK bank holiday, for example, London desks are lightly staffed, EURGBP and GBP crosses behave strangely, and the whole European morning feels different. On a US holiday, USD pairs trade in a half-asleep market, with moves that look large on the chart but occur on tiny volume.

Spreads are the first clue. They often run wider than normal at times when they would usually be tight. Slippage tends to increase, and price can jump between levels because fewer orders fill the gaps in between.

Strategies calibrated on regular days can misfire. A volatility filter based on ATR might read low and permit trades that behave badly. A breakout from a thin range may fail because there's nobody to follow through.

Keeping a calendar of holidays in the major financial centers, not just the home country, is worth the five minutes it takes.

Which holiday has been the most surprising in terms of how a pair behaved?