Freddie Mac released its weekly update on national mortgage rates this morning, showing a continued rise in interest rates -- nearly across the board.

Thirty-year and 15-year fixed rate mortgages (FRMs) rose eight basis points apiece in comparison to last week, hitting 3.59% and 2.77%, respectively.

Among variable rate mortgages, 5/1 adjustable rate mortgages tacked on one basis point, rising to 2.63%. One-year ARMs stayed flat at 2.55%.

In a statement, Freddie Mac vice president and chief economist Frank Nothaft observed that this is the third week in a row that FRMs have risen and mused that this trend "may slow some of the refinance momentum." Even so, "rates are nonetheless low and home-buyer affordability high, which should further aid home sales and construction in coming weeks."

Nothaft noted that even at the higher rates, "the National Association of Realtors reported that the median number of days on the market for these sales fell from 62 to 46 days, the fewest since it began collecting the data in May 2011."

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