By Barani Krishnan

 NEW YORK, Oct 21 (Reuters) - U.S. crude oil tumbled below $100 a barrel for the first time since July on Monday amid fears
of excessive near-term supplies, and most other commodities closed lower too on uncertainties about demand.

 A stronger dollar versus the yen added pressure to
commodities denominated in the U.S. currency. The Thomson Reuters/CoreCommodity CRB index fell
0.6 percent, with 10 of the 19 futures markets tracked by the index ending in negative territory. 

Natural gas led the declines, sliding 2 percent, as growing inventories encouraged investors to cut their positions
despite upcoming colder weather that will force more homeowners
and businesses to crank up their heaters. 

Arabica coffee, U.S. crude, orange juice and wheat were other significant losers, each closing down
about 1 percent or more.  In oil, the discount of New York-traded crude versus
Europe's Brent hit its widest in six months as diminished oil
inventories in the U.S. Midwest began to grow.

 New York's West Texas Intermediate (WTI) crude fell $1.59 to settle at $99.22 a barrel for the front-month contract.
Brent's benchmark contract slipped just 30 cents to
close at $109.64 a barrel. 

 The December premium for Brent to WTI ballooned by $1.30 to more than $10 a barrel. The December WTI contract also fell to a
discount versus January, a structure known as contango,
signaling a near-term excess of oil.

 Seasonal refinery maintenance and shifting pipeline flows around the key Cushing, Oklahoma, oil hub have helped reverse a
months-long decline in WTI stockpiles, dramatically shifting the oil market's structure over the past two weeks.

 Now, instead of a squeeze on supplies, traders are betting on a near-term surplus of inventories, at least until
ramped-down refineries begin to rev up operations again. Delayed
U.S. government data for the week to Oct. 11 confirmed the first
decline in Cushing stocks in 14 weeks, while industry data
suggested the drawdown had continued since then.
    "That crude build stood out," said Gene McGillian, analyst
with Tradition Energy in Stamford, Connecticut. "After last
week's API data there are signs that we have strong production
levels and ample supplies."
    
 Prices at 5:09 p.m. EDT (2109 GMT)      
                              LAST/      NET    PCT     YTD
                              CLOSE      CHG    CHG     CHG
 US crude                     99.05    -1.76  -1.8%    7.9%
 Brent crude                 109.77    -0.17  -0.2%   -1.2%
 Natural gas                  3.668   -0.096  -2.6%    9.5%
 
 US gold                    1315.80     1.20   0.1%  -21.5%
 Gold                       1315.54    -0.21   0.0%  -21.4%
 US Copper                     3.30     0.00   0.1%   -9.8%
 LME Copper                 7244.00    -1.00   0.0%   -8.7%
 Dollar                      79.695    0.041   0.1%    3.8%
 CRB                        285.337   -1.581  -0.6%   -3.3%
 
 US corn                     444.00     2.50   0.6%  -36.4%
 US soybeans                1303.25    12.00   0.9%   -8.1%
 US wheat                    699.75    -6.00  -0.9%  -10.1%
 
 US Coffee                   112.70    -1.95  -1.7%  -21.6%
 US Cocoa                   2730.00     9.00   0.3%   22.1%
 US Sugar                     19.42    -0.08  -0.4%   -0.5%
 
 US silver                   22.233   22.014   1.7%  -26.4%
 US platinum                1435.70     0.90   0.0%   -6.7%
 US palladium                749.25     9.60   1.3%    6.5%