Spring is here and after the collective near-death experience of late 2008 global markets are in euphoric mood.  Stock markets continue to power upwards, commodities are coming back in favour and previous safe-haven sanctuaries like the dollar and the yen are being deserted.

The LME complex has been basking in the spring sun, thanks to increasing confidence the worst of the manufacturing meltdown is now over and rising hope that demand for industrial metals could snap back just as quickly as it collapsed.

The following table shows the breadth of price strength since the start of the year with only one LME component, the Mediterranean steel billet contract, still in the red.

                        Close     Chg on Week    Pct Chg  Pct Chg on Year

 Aluminium        $1,544          +$5            +0.3     +0.3

 Copper             $4,685         +$85           +1.9     +52.6

 Lead                $1,465       +$65           +4.6     +46.7

 Nickel               $13,100     +$1,200        +10.1    +12.0

 Steel FE            $355         +$10           +2.9     +6.0

 Steel Med         $332.5      -$7.5          -2.2     -12.5

 Tin                  $14,000    +$1,550        +12.5    +30.8

 Zinc                  $1,555    +$40           +2.6     +28.7

However, after such a surprisingly robust early year performance, is it now time to heed that old stock market adage: sell in May and go away?

CHINA GEARING DOWN?

The sell in May strategy has a real-economy underpinning when it comes to industrial metals.

There is a distinct seasonality to metals buying patterns with restocking buoyancy in the spring fading ahead of the dog days of summer, when northern hemisphere fabricators take holiday downtime.

China, note, is no exception to this rule.

Even while the dragon's appetite continues to suck metal out of the LME warehouse system, there is growing evidence that the Shanghai market is losing some of its white heat ahead of what locals call the low season.

Most significantly, stocks of metal registered with the Shanghai Futures Exchange are growing again. Aluminium inventory has risen for five straight weeks, zinc for three weeks and copper for two weeks. Without anyone quite noticing, zinc inventory at 80,074 tonnes is at a life-of-contract high.

Shanghai copper stocks are rebuilding from an extremely depleted base and at 27,690 tonnes are still very low by any historical yardstick. But rising visible stocks are being accompanied by a lessening of the Shanghai front-month backwardation and by a gradual closing of the London-Shanghai arbitrage, through which hundreds of thousands of tonnes of metal have been flowing since the start of this year.

The arbitrage is still open, just, but as one Chinese trading house manager told Reuters last week, the risk is high given the low season is coming.

NO-ONE ELSE GEARING UP?

China, at least, has managed to restock. There is little evidence that consumers in the developed world have replenished thread-bare inventory levels, which should be a positive for the metal markets.

But do they need to restock now? Although macro indicators point to a stabilisation and small recovery in global manufacturing activity, the metals supply chain remains under tremendous stress.

Detroit is still a black hole of metals demand.

Crucible Materials, a U.S. supplier of specialist steel to the transport sector, last week filed for bankruptcy. In the same week AK Steel issued a Q2 profits warning, Severstal announced more capacity closures in North America and aluminium products manufacturer Kaiser shuttered its Bellwood plant in Virginia.

Meanwhile, big one-off inflows of metal into the LME system such as the 8,775 tonnes of copper warranted at Liverpool or the 9,624 tonnes of nickel that suddenly appeared at Singapore are a reminder that there is no shortage of physical metal out there. In the case of aluminium, the reminder comes daily with each warehouse stocks report.

For many commentators, this bleak landscape is a clear sell signal. Credit Suisse analysts, for example, warn that in the absence of Chinese strategic buying, real demand remains weak while inventories are plentiful. The bank's advice to clients is a simple: Use the current rally as a selling opportunity.

BUT SELLER BEWARE!

Others are not so sure. The metals team at RBC Capital Markets, for instance, was last week advising those customers lucky enough to have ridden the early 2009 rally to take profits but warned that outright short plays are in our view all too dangerous.

There are several good reasons for such caution.

Firstly, Chinese buying may be losing its strength but it is still a key influence in copper in particular, where the search for available LME units has now spread from Asia (none left) to Europe (rapidly dwindling) to the United States. Cancelled copper tonnage at New Orleans stands at 17,750 tonnes. Just over a month ago it totalled exactly zero.

While LME stocks are still falling, going short is a risky strategy.

Would-be bears should take heed of events in the tin contract. LME tin stocks have not rebuilt to any comfort zone, the front part of the curve remains heavily backwardated and the market is little more than the plaything of predator funds.

Secondly, technical players do not care that much about fundamentals. They care about technical signals and these are currently still pointing upwards. All the LME base metals, with the exception of aluminium, have either broken or are challenging 200-day moving averages, a key indicator for the technically-minded.  The CTA fund herd has now covered back short positions (again with the exception of aluminium) and is starting to build long positions.

Thirdly, many of the bigger macro funds have completely missed the 2009 base metals rally and are now itching to pull the trigger as economic indicators pick up. A mass entry by such laggards could generate a next leg up in prices by interacting with the trend-following black box CTA community.

Fourthly, rising risk appetite will pressure the dollar, creating another possible positive feedback loop for the commodities asset class as a whole.

TENSION

Readers will note the pros and cons for selling in May fall into two broad categories: fundamentals, which support the proposition, and technicals, which do not.

This dichotomy lies at the heart of the current tension in the LME complex.

Funds are becoming enthused about metals just at the time that Chinese buying looks to be gearing down without any offsetting pick-up elsewhere.

As such, there is not yet a consensus answer to the sell in May question.

But the tension between fundamental and technical indicators cannot exist for any extended period of time. May will be pivotal to determining the next bigger move in the industrial metals complex. It's just not clear yet what that move will be.

 (Editing by Sue Thomas)

© Thomson Reuters 2009 All rights reserved

* Andy Home is a Reuters columnist. The opinions expressed are his own. For more Metals Insider columns, top Reuters metals stories and third party content, please visit the free Base Metals Community website at (www.metalsinsider.com)

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