Century Aluminum (CENX) has a bear flag pattern.

Several markets are now stretching towards extremes: gold is now above $1000 per ounce in European trading, the US dollar is breaking down to a key support level against the Swiss franc, and the S&P futures in European trading are above 1020.

The homebuilding sector, as available via the XHB fund, illustrates clearly a pattern which is visible on many charts: the failure by momentum indicators to confirm the bullish price action in the second half of August.

The weekly chart for gold suggests the metal is now on the verge of either a major breakthrough which could propel it far beyond $1000 or a failure at what would be its fourth attempt to regain the levels above $1000 per ounce from March 2008.

PBW, an ETF which tracks clean energy stocks, has broken below key support levels.

If the dollar strengthens today on weakness in US equities, this will act as a rather powerful feedback loop putting more strain on equities, emerging markets and commodities.

Corning (GLW) registered a hanging man candlestick pattern just above the 50-day EMA and would be worth monitoring today for signs of weakness.

KBE, the exchange traded fund which tracks the KBW Banking Index, is suggesting that, without any obvious earnings sizzle to inspire buyers, the banking sector may have already priced in a lot of the more optimistic mood music.

The chart for Bank of America (BAC), shows the kind of rolling top pattern which often precedes a correction.

UUP, the exchange traded fund which takes a bullish view on the US dollar index, is displaying a lot of positive divergences and there is clear evidence of accumulation.