Just half an hour to go to crucial US CPI

We're into Friday afternoon in Europe and finally the most important scheduled data release of the week, U.S. CPI, is here.

It'll be a really important one as markets are currently seeing around a two-in-three chance of a Fed rate hike next week, and so a cooler or hotter print could shift that meaningfully.

Consensus stands at 0.2% month-on-month for core CPI and 0.4% for headline, and with expectations so finely balanced, we may be into the crazy situation where if core is at 0.249%, and so rounds to 0.2%, we get a different Fed path from if it comes in at 0.250%, and so rounds to 0.3%.

"The Fed is in a corner of its own making - Warsh didn't signal a hike at Jackson Hole but the market is daring him to do it and won't be satisfied now until it happens," said Neil Wilson, UK investor strategist at Saxo.

"Leaving aside why Fed officials can be swayed by a 0.1 ppt difference for a single month after more than five and a half years of above-target readings, it nevertheless means there is an unusually high degree of uncertainty and risk associated with this event."

With bond markets under pressure, what the Fed does in September will also be more important than usual.

The 10-year Treasury yield is currently at 4.95%, and, says Kenneth Broux, an analyst at Societe Generale: "the Road to 5% Runs Through CPI".