Fortescue founder Andrew Forrest has seen the iron ore miner's shares fall 10% this year.

Fortescue founder Andrew Forrest. The company now expects to ship 127mt of iron ore in fiscal 2014. Photo: Jacky Ghossein

Fortescue Metals’ shares fell by as much as 5.5 per cent after it announced that weather problems will force its total iron ore shipments toward the bottom end of previous guidance.

The iron ore miner had originally promised to export between 127 million and 133 million tonnes in the 2014 financial year, but it today predicted that it would export exactly 127 million tonnes.

The shares fell 3.4 per cent to $5.12 at about 1pm AEDT on Thursday from $5.22 shortly before the results were published.

Fortescue said the change was the result of “significant weather related production impacts in January 2014”, which appears to be a reference to severe cyclone activity over the Christmas and New Year period.

Rival Pilbara miner Rio Tinto also blamed the cyclones and storms during that period for hampering its iron ore exports, when it reported to the market on January 16.

Not surprisingly, Fortescue’s exports in the December quarter were slightly lower than analysts had expected, with Fortescue shipping 28 million tonnes compared to the 29.02 million tonnes that JP Morgan had expected.

The slightly weaker production was not the only minor disappointment in the quarterly, with Fortescue confirming that its expansion to a production rate of 155 million tonnes per year had blown out by $200 million.Engineering costs up

The cost increase related to extra engineering work and commission costs associated with the new Kings mine in the Pilbara.

Fortescue had previously promised to spent $US1.9 billion on capital expenditure in the 2014 financial year, but that will now rise to $US2.1 billion.

The 30-month expansion to 155 million tonnes is now likely to cost just over $US10 billion, if the cost of trucks and other fleet items are included.

Fortescue enjoyed a strong iron ore price during the first half, with the received price averaging a very healthy $US124 per tonne.

Iron ore price was fetching $US122.60 per tonne this morning, well below the $US135 per tonne it was fetching on January 2.

Fortescue shares have slid in recent weeks in line with the declines in the iron ore price, and speculation has raged that new environmental rules in China will make some of Fortescue’s lower grade iron ore less valuable.

But the company appears undeterred, and plans to introduce a new, lower grade product within six months.

Morgan Stanley has also been underterred by those price slides, saying this week that it expects the share price falls to cease soon.

Morgan Stanley said much of those falls were due to seasonal factors affecting the iron ore price, and it said there was a ‘’high probability” that Fortescue shares would rise over the next six weeks.

Fortescue also reported two workplace deaths over the past six months, and the company announced today that aside from the regulatory investigations into those two incidents, it had commissioned an external company to conduct a “whole of business” review of safety management at every Fortescue site