The volatility continued in the Nifty index ahead of the crucial US FOMC meet outcome. The index lower-end support stands at 15,500 where fresh put writing has been observed and if fails to sustain above it will witness further selling pressure. The upper-end resistance stands at 16,000 where the highest open interest is built up on the call side. The Bank Nifty index witnessed a range-bound trading session and will witness sharp movement on either side post the FOMC meeting. The immediate upper-end hurdle stands at 34,000 and a breach above that will lead to fresh short covering. The lower-end support stands at the 33,000-32,500 zone which has earlier acted as the demand zone.