By Ryan Davis
    Of DOW JONES NEWSWIRES
 
 
   CHICAGO (Dow Jones)--Chicago Board of Trade corn futures closed markedly
 lower Thursday on an increasingly benign weather forecast, slipping crude-oil
 prices and a last-minute surge of month-end liquidation, traders and analysts
 said.
 
   September corn closed down 14 cents to $5.87 1/2 per bushel, December corn
 closed down 13 3/4 cents to $6.07 1/2 and March corn closed down 13 3/4 cents
 to $6.27 1/2.
 
   Thursday ended a streak of five straight higher closes as corn followed
 crude-oil prices down, traders and analysts said.  In contrast, crude-oil
 prices buoyed corn prices Wednesday and helped them settle markedly higher.
 
   Coupled with a general lack of fresh fundamentals, crude oil's break was a
 core component in corn's slip, analysts said.
 
   Another was an increasingly benign weather forecast. Analysts said that
 above-average heat and humidity across the U.S. corn belt, seen as potentially
 threatening earlier in the week, could prove somewhat beneficial to the crop.
 
   "Despite all the trepidation about the heat moving in, the temperatures
 aren't that extreme, and it's not that long lasting," said Joel Karlin, sales
 manager and commodity-sales coordinator at Western Milling.  "For some areas
 that are a little bit behind, an increase in the heating-degree days is
 probably a little bit welcomed."
 
   Accompanying humidity could also prove beneficial to the crop, said Shawn
 McCambridge, senior grains analyst at Prudential-Bache.  These are "pretty much
 ideal conditions for the corn crop at this point," he said.
 
   Prices were down all day and dropped even further late in trading due to
 month-end liquidation, traders said.
 
   Other factors leading to corn's decline was a lackluster export-sales report
 and a general cool-down in end-user buying caused by recent gains in the
 market, traders and analysts said.
 
   "Export sales have definitely slowed compared to where they were earlier in
 the year because of the prices," said Karlin, stressing the still historically
 high price of corn.
 
   Export sales were reported Thursday at 888,900 metric tons for the 2007-08
 and 2008-09 marketing years, at the high end of analyst estimates.
 
   Recent gains in the market are also tempering a potential rally, traders and
 analysts said.
 
   "There's not much of a new reason for buyers to step in off of the sidelines
 at this point," said McCambridge.
 
   CBOT oats futures ended lower. A trader said the market was pressured by fund
 liquidation, while commercial buying provided some support to 2009 contracts.
 September oats were down 7 1/2 cents to $3.77 1/2, December oats were down 7
 1/2 cents to $3.97 and March oats were down 7 cents to $4.16 1/2.
 
   Ethanol futures were slightly lower. September ethanol ended down $0.004 to
 $2.446 per gallon and December ethanol ended down $0.020 to $2.430.