CHICAGO, July 27 (Reuters) - Chicago Board of Trade soybean futuresseesawed throughout Tuesday's session before ending mostly lower asdiffering views about weather outlooks and a volatile cash basis kepttraders on edge, floor brokers said.CBOT soy futures closed 3-1/2 cents per bushel lower to 1/2 centhigher. Old-crop August ended 3-1/2 lower at $6.65-1/2 -- after seeing a26-cent price swing and climbing 17 cents shortly after the open. Earlystrength came from renewed concerns about a 27-year low in U.S. soy stocksand a step-up in Midwest processor bids. The market was also technicallyoversold and due for correction.But it didn't take long for August to lose steam once new-crop soybeansturned lower. New-crop contracts were higher early on 11- to 15-dayoutlooks for hotter, drier weather moving into the Midwest as soybeansbegin setting pods."Even though the longer-range maps had much above normal temperaturescoming into the Corn Belt there's certainly a lot of skepticism that theheat will actually be a factor. That brought a lot of choppy trade," saidDan Cekander, an analyst with Fimat Futures.New-crop November ended unchanged at $5.97 but was also volatile,rallying 10 cents then falling 11 cents. Expectations of a record-largeU.S. soy crop, with some talking about a 3.0 billion bushels crop remainsbearish. Crop conditions continue to improve. USDA late Monday rated 69percent of the U.S. soy crop as good to excellent, up from 68 percent lastweek.The roller coaster ride continued about midday when August recoveredamid strong commercial bull spreading. ADM Investor Services spreadroughly 800 Aug/Nov and 300 Aug/Sept. CIF offers for July at the U.S. Gulfalso spiked higher, up 40 cents by midday. The jump in CIF values sparkedtalk of Chinese interest in U.S. soybeans, but there was no confirmationof a sale.The cash basis was volatile as well. There were reports that the cashbasis appreciated at some Midwest locations, while others remained steadyto softer, floor traders said.Soymeal futures ended 90 cents per ton higher to $1.50 lower, with thefront months up on a technical recovery. August closed 90 cents higher at$212.70. The market was due for a bounce as the nine-day RSI for Augustdipped to 9 as of Monday's close. Funds bought about 1,100 meal futures.The soymeal market has followed the recent weakness in soybeans andremains under pressure from a soft U.S. cash meal market, traders said.CBOT soyoil futures ended 0.01 to 0.25 cent per lb lower, with August down 0.25 at 24.24 cents, pressured by the lower close in soybeans.Funds ended about even in soyoil and soybeans.Malaysian palm oil futures closed mixed. Concerns about a smalleroilseed crop in India due to poor monsoon rains remains supportive to bothpalm oil and soyoil futures.Estimated soybean volume was 67,875 futures and 20,531 options, up from63,449 traded Monday. Soymeal trade was pegged at 37,199 futures, downfrom Monday's 39,901, and 2,634 options. In soyoil, an estimated 28,868futures and 3,285 options traded. That compared to 28,832 traded onMonday.