The 30-year fixed-rate mortgage averaged 6.23%, up 2 basis points from a week ago and 13 BPS higher than the level a year ago, according to Freddie mac’s latest Primary Mortgage Market Survey.

“Interest rates drifted slightly higher following the latest positive economic reports,” said Frank Nothaft, Freddie chief economist, in a written statement. “Shoppers bustling through the holiday season boosted December’s retail sales above consensus expectations. In the same month, industrial production reversed a three-month decline and rose faster than had been anticipated.”

Federal Reserve Chairman Ben S. Bernanke warned that even though official projections suggest that the unified budget deficit may stabilize or moderate further over the next few years, “we are experiencing what seems likely to be the calm before the storm,” according to his prepared testimony before the Senate Banking Committee today.

Bernanke noted that spending on entitlement programs will begin to climb quickly during the next decade and “put enormous pressure on the federal budget in coming years.”

Budget deficits push government borrowing and interest rates higher.

The Fed chief added, “if early and meaningful action is not taken,” such as reforming programs like Social Security and Medicare, “the U.S. economy could be seriously weakened, with future generations bearing much of the cost.”

Freddie’s Nothaft noted that in the coming year, inflation is expected “on average to remain moderate at 2.5 percent, barring shocks from the energy sector, but concerns over the level of core inflation will continue to cause mortgage rates to fluctuate.”

Over the next 35 to 45 days, rates will remain relatively unchanged, according to 60 of the 100 mortgage “experts” surveyed by Bankrate.com this week. Another 30 forecast a rise in rates and the rest a downfall.

Accordingly, the Mortgage Bankers Association expects the 30-year to average 6.2% this quarter, but rise 10 BPS next quarter and climb to 6.5% for the second half of the year. The highest Freddie sees the average going throughout the year is 6.3%.

The 15-year, at 5.98%, also ticked up 2 BPS from last week, Freddie said.

The 10-year Treasury note yielded 4.74% near the market’s close today, up about 1 BPS from last week.

The 5-year Treasury-indexed hybrid adjustable-rate mortgage averaged 6.04%, just 1 BPS above a week earlier.

The largest weekly increase — 7 BPS to 5.51% — occurred in the 1-year Treasury-indexed ARM average. The 1-year Treasury bill itself, at 5.08% Wednesday, climbed 6 BPS from a week earlier, according to Fed data.

The ARM share of total mortgage applications managed to edge up to 21%, according to the Mortgage Bankers Association.

Overall, originators completed about 1 percent fewer applications in the week ending Jan. 12, as a 7 percent decrease in purchase money demand overshadowed a 6 percent increase in refinance requests, MBA reported.

The refinance share ticked up from the previous week to comprise half of all applications, MBA said.