The analyst firm's FutureScan forecast is now predicting IT investments for the coming 12 months to increase by only 2.9 per cent, down from last month's prediction of 6.1 per cent.
"Most of the economic forecasts around the impact of Katrina seem to indicate a short-term hit to the US economy in 2005, followed by a rebuilding rebound in 2006," said John Gantz, chief research officer at IDC.
"As this news gets absorbed by IT and business executives, we expect their IT spending expectations to recover."
The analyst recommended that the IT industry should pay close attention to petrol prices this winter. If the price of fuel further increases, consumer spending could be affected, hurting corporate revenues and IT investments.
IDC bases its IT spending forecasts on a measurement of supply and demand of IT products.
Microsoft seizes control of phishing sites linked with Russian state hackers
Fitness trackers over-estimate the number of steps their users take, analysis of 67 research reports suggests
Everything we think we know about the imminent Apple iPhone 9, iPhone 11 and iPhone 11 Plus launches
All the latest rumours about Apple iPhone Displays, CPUs, launch dates and even prices
Nvidia brings Turing microarchitecture into the high-end gaming segment