PREVIEW-S&P/Case-Shiller 20-city seen up 0.8 pct in September

* What: S&P/Case-Shiller September home prices indexes

* When: Tuesday, Nov. 24, 9 a.m. (1400 GMT)

* Economists' median forecast: +0.8 pct for 20-city index

-9.0 pct yr-over-yr 20-city

NEW YORK, Nov 23 (Reuters) - U.S. home prices likely rose
in September for the fifth straight month, trimming the year's
losses, a Reuters survey on the Standard & Poor's/Case-Shiller
indexes found.

The S&P/Case-Shiller 20-city index rose by 0.8 percent in
September after a 1.2 percent August gain, according to the
median forecast from 14 economists. Estimates ranged from a 0.5
percent decline to a 2.2 percent increase.

The expected rise would result in a 9 percent annual drop,
based on a survey of 31 economists. That would be an
improvement over the 11.3 percent annual drop reported for
August. Forecasts ranged from an annual drop of 8 percent to a
11.2 percent downturn.

The home price data will be announced on Tuesday at 9 a.m.
by S&P, which will also report its national index for the third
quarter.

Some economists expect foreclosures to increase unsold
inventory and pressure prices further before hitting bottom in
2010.

Most economists, however, said the worst of the three-year
plunge was done and any further erosion would be relatively
modest. Through August, prices fell an average of about 30
percent from the mid-2006 peak, based on the 20-city index.

Sales of existing homes in October shot up 10.1 percent to
the highest in more than 2-1/2 years as buyers rushed to take
advantage of a federal tax credit, the National Association of
Realtors said on Monday. Read more at [ID:nN23250199].

The national median home price fell 7.1 percent from
October 2008, the smallest decline in over a year, NAR said.

A sampling of S&P/Case-Shiller forecasts and analysis
follows:

UBS:

FORECAST: +0.2 pct 20-city monthly

-9.6 pct year-over-year

+2.2 pct national Q3 vs Q2

-9.6 pct national Q3 vs Q3 2008

"Home prices have turned upward since Q2, probably
reflecting a combination of strength in underlying demand, a
temporary boost from the homebuyer tax credit, a mix-shift away
from sales of distressed homes, and a boost from seasonal
factors through late summer.

"However, other monthly indicators of prices began to
weaken in August and September. The S&P/Case Shiller composite
20 index will probably lag, partly because it is based on
three-month moving averages. The September reading will reflect
transactions in July, August and September.

"We expect further weakening in prices in coming months
because the homebuyer tax credit probably pulled forward some
demand."

ACTION ECONOMICS:

FORECAST: +0.8 pct September 20-city

"We expect a 0.8 percent September gain, which would
reflect some moderation in the recent home price bounce from
the out-sized 1.2 percent to 1.6 percent gains in each of the
last three months that we believe overstate the degree of
stabilization in the housing market over the summer months."

"The 0.8 percent September gain should allow the y/y rate
of decline to diminish to -8.9 percent from -11.3 percent in
August, and we expect this y/y measure to reclaim positive
territory by January."

BOFA MERRILL LYNCH RESEARCH:

FORECAST: +0.7 pct 20-city monthly

-9.0 pct 20-city year-over-year

-5.0 pct national Q3 quarter-over-quarter

-12.7 pct national Q3 year-over-year

"The true test of a bottom in prices will occur this
winter, when the market will be grappling with a new round of
foreclosure supply.

"The 3Q national price index is expected to show an
annualized quarter-over-quarter decline of 5 percent, following
a 5.8 percent gain in 2Q. This would translate into a
year-over-year decline of 12.7 percent for a peak-to-trough
drop of over 31 percent. Downside of at least another 5 percent
still lies ahead, with the bottom occurring by early 2010."

BARCLAYS CAPITAL:

FORECAST: -0.5 pct 20-city index September

-10.2 pct 20-city year-over-year

+1.2 pct national index Q3 vs Q2

-10.5 pct national index year-over year

"We expect the national index to decrease 10.5 percent y/y,
which would be a 1.2 percent quarter-over-quarter seasonally
adjusted annual rate (saar) gain. This would be consistent with
the gain in the 20-city composite over the first two months of
the quarter and our forecast for a decline in September.

"We believe the volatility owes to seasonal distortions
related to the share of distressed sales, which biased home
prices higher over the prior three months but should now start
to reverse. This pattern was also evident in other measures of
home prices, including Loan Performance, Radar Logic, and FHFA.

"We expect home prices to drop at an accelerating pace
through the rest of 2009 and find a bottom at the end of Q1
2010."
(Reporting by Lynn Adler; polling by Bangalore Polling Unit;
Editing by Leslie Adler)
((lynn.adler@thomsonreuters.com; +1 646 223-6307; Reuters
Messaging: lynn.adler.reuters.com@reuters.net))