U.S. home prices spiked 13.7 percent last November, according to the Case-Shiller Home Price Index, in a sign that the rapid price appreciation of 2013 may continue through the winter, normally a slow time for sales when prices dip. 

Case-Shiller’s 20-City Composite increased 13.7 year-over-year. Boston prices rose 9.8 percent year over year, according to the index, but it was the western states that saw the steepest gains, with Las Vegas prices increasing over 27 percent and San Francisco prices up over 23 percent. Dallas and Chicago also has exceptionally good months, with Dallas’ 9.9 percent increase its highest annual return since Case-Shiller began tracking it in 2000, while Chicago’s 11 percent rise was its highest since December 1988.

Month over month, the index was down 0.1 percent from October, the first decrease since November 2012. Boston prices, however, were up 0.2 percent compared with last month.

"November was a good month for home prices," David M. Blitzer, chairman of the index committee at S&P Dow Jones Indices, which publishes the index, said in a statement. "Despite the slight decline, the 10-City and 20-City Composites showed their best November performance since 2005. Prices typically weaken as we move closer to the winter … Combined with low inflation-1.5 percent in 2013-home owners are enjoying real appreciation and rising equity values. While housing will make further contributions to the economy in 2014, the pace of price gains is likely to slow during the year."