Investors must be careful in the week ahead as Yellen's testimony before Congress and the UK's referendum will most likely be the main drivers for the pair, although there are some macro data on the agenda. Forex - EUR/USD Weekly Outlook: Yellen's Speech & Brexit Referendum to Cause Volatilty London - The week ahead might be very volatile, mainly due to the Brexit referendum on Thursday, but investors might focus on some macro updates from both the euro zone and the United States. The European calendar starts on Tuesday, with German ZEW surveys for June on the agenda, however, the euro rarely reacts in a volatile way ... (full story)