Rolling into the NY rollover we're seeing spreads widen on GBP/USD by as much as 30 - 40 pips, (normally, GBP/USD about 2-4 pips wide):
It's also interesting to see GBP/USD gap - major currencies almost never do this:
Most Forex brokers/banks have lowered leverage for GBP pairs leading up to today's vote, and will resume to normal at the start of next week's trading (probably).
Many traders have turned off their algos, because of the unknown risks how markets may react. This gap and spread widening at this quiet time - it's a sign that it's going to be a very long night for US traders, as final results will not come in until 2am EST. That's just 2 hours before the official UK open around 4am EST, and it's a friday. Traders will want to spend the weekend risk-off so expect a volatile friday both EU and NY sessions as traders clear their books of any GBP exposure. If UK votes to Brexit, which doesn't look likely at the moment - expect massive volatility FX has never seen.
Don't forget - the Great British Pound was once the world's reserve currency. London is the FX capital of the world. It's called 'Sterling' because one 'pound' was worth literally - one pound of fine sterling silver.
While Brexit will rock financial markets - let's remember that at the end of the day, it will take 2 years for Brexit to actually happen and even when it does, it only transfers power from Brussels back to London - effectively nothing changes. This is explained well in this article "EU Government Deception" Will life improve for the average British citizen? Probably not. Will the rich be impacted? Probably not, as they have world-class asset managers that have carved up ways to profit from Brexit. So what's all the fuss about - really?
Because it's a harbinger of 'populism' - demanding 'better' management from their owners. If you want to understand Brexit better, don't put out food for the cat tonight, see how they react. Finally, you'll be forced to put something in their bowl.
If you want to understand more about the Forex mechanism behind Brexit, and how Forex is a social control paradigm, checkout Splitting Pennies - Understanding Forex.