Heavy flooding in Thailand will directly impact PC markets in the first half of next year, though they will not hamper this holiday season’s sales significantly, according to IDC.

The research firm said that PC shipments could fall more than 20% from previous forecasts in the first quarter of 2012.

Thailand accounted for 40-45% of worldwide HDD production in the first half of 2011. As of early November, about half of this capacity has been directly impacted by the flooding waters. Another problem that would plague this industry in Thailand for some time would be work stoppages due to poor access and power outages.

However, the full impact of the damage to HDD industry factories cannot be ascertained until the flood waters recede.

According to IDC, HDD industry participants will be able to recover and restore HDD production capacity relatively quickly.

But IDC asks PC vendors to plan for and expect significant HDD shortages by mid-November 2011 that will continue into 1Q 2012, higher HDD prices as demand exceeds supply and manufacturers face increased costs for components, expedited shipments and shifting of production to new locations.

IDC Worldwide Consumer Device Trackers program vice president Loren Loverde said the HDD shortage will affect smaller PC vendors and lower priced products most, including mini notebooks (aka netbooks), emerging markets and entry-level consumer PCs.

"However, even the largest vendors are expected to face HDD shortages, particularly for portable PCs where the market is more consolidated," Loverde said.

The IDC has released a study entitled, "The PC Market Is Disrupted By HDD Shortages: The Severity, Resulting Opportunities, And Expected PC Market Reactions," which assesses the impact of hard disk drive shortages caused by widespread flooding in Thailand on the PC market in Q4 2011 and the first half of 2012.