By Barbara Kollmeyer, MarketWatch

Critical information for the U.S. trading day

Signals out of what is shaping up as the most important OPEC summit in two years are not encouraging.

Talk of discord between members, a Russia no-show (https://t.co/U3boNa57as) and failed premeeting meetings (http://www.reuters.com/article/us-opec-meeting-idUSKBN13N0Q6) have been dogging crude, which is sharply lower this morning. Goldman Sachs, for one, points out Brent futures are pricing in a just 30% chance (http://www.marketwatch.com/story/why-the-opec-meeting-is-likely-to-disappoint-in-one-chart-2016-11-29) of a production-cut deal getting done. Others are putting the odds of success on Wednesday at less than that (http://oilprice.com/Energy/Energy-General/Suckered-Again-How-Likely-Is-A-OPEC-Production-Cut.html).

Our call of the day says the next 24 hours will be crucial for all markets.

If no deal is agreed (http://www.marketwatch.com/story/why-saudi-arabia-might-walk-away-from-an-opec-oil-output-deal-2016-11-29), that will hit not just oil, but also forex and equity markets from Middle Eastern stocks to Wall Street, says Naeem Aslam, chief market analyst at Think Markets.

Aslam thinks OPEC will toss markets a small bone. Even so, he warns that Wall Street is vulnerable, because upward momentum for stocks has been in part underpinned by the recovery in oil prices this year. The other driver -- the U.S. election -- can't juice this market until investors see what the new Trump administration will do.

Aslam says the S&P 500 could drop well below 2,100 if OPEC fails. "If there is no deal, the Saudis are going to make sure they dump the market with as much oil as possible because now the real trade war will begin and they will not care about anything." That means squeezing out the small players and oil in the mid $20s. Ugly for stocks.

If doomsday happens, the bright spots will be airlines and ocean shipment companies, both which benefit from weak oil.

Key market gauges

Futures on the Dow and S&P are holding a bit higher. Gold and silver are pulling back, while the dollar is up against the yen, but down elsewhere. See more in Market Snapshot (http://www.marketwatch.com/story/us-stocks-on-pace-for-muted-open-as-analysts-argue-traders-got-carried-away-2016-11-29).

Crude is under pressure as the markets watch the newsfeed. Asia finished mostly lower, while Europe is marginally higher.

The chart

Gold has taken a nearly 7% hit this month, and it can't seem to get back to $1,200 an ounce.

Blogging for See It Market (https://www.seeitmarket.com/spdr-gold-etf-gld-hits-key-fibonacci-price-support-trading-16306/), Dana Lyons says gold needs stocks and/or the dollar to weaken to get going again. For now, he's keeping an eye on a key technical support level for the SPDR Gold Trust exchange-traded fund (GLD) .

"After breaking most trendlines, key moving averages and other such potential support, GLD is now nearing a 61.8% Gold Fibonacci Support (retracement) of its December-July rally. This may be the gold bugs' last best chance to halt the decline," says Lyons, a partner at J. Lyons Fund Management.

According to this Fibonacci explanation (http://www.investopedia.com/terms/f/fibonacciretracement.asp), that 61.8% support is extremely significant to tech watchers. Either the final sellers throw in the towel, and bargain hunters rush in; or the final buyers unload, and short sellers jump in to push prices lower.

Another view on gold comes from Kimble Charting Solutions (https://www.kimblechartingsolutions.com/2016/11/gold-miners-testing-triple-support-32-decline/). They look at the VanEck Vectors Gold Miners ETF (GDX) , which is also nearing a critical support level.

The buzz

Giving Tuesday is upon us. Here are the apps to make it happen (http://www.marketwatch.com/story/these-5-apps-will-make-donating-easy-this-giving-tuesday-2016-11-28)

Tesla (TSLA) is under fire from the SEC over "tailored" accounting methods (http://www.marketwatch.com/story/sec-knocks-tesla-over-tailored-accounting-in-earnings-release-2016-11-28).

People Magazine publisher Time (TIME) has reportedly rebuffed a takeover offer from Edgar Bronfman Jr. and the owner of Warner Music, a source told DealBook (http://www.nytimes.com/2016/11/28/business/dealbook/time-inc-is-said-to-turn-away-from-a-takeover-by-edgar-bronfman.html?_r=0).

Congress on Monday night backed a bill that protects people who post (http://abc27.com/2016/11/28/congress-backs-bill-on-customer-rights-for-online-review/) negative reviews on Yelp or Trip/Advisor from legal backlash. It now goes to the desk of President Barack Obama.

The economy

Ahead of Friday's big jobs report, we've got third-quarter GDP at 8:30 a.m. Eastern Time, Case-Shiller home prices at 9 a.m. Eastern, and consumer sentiment an hour after that.

Among Fed speakers, William Dudley is skedded at 9:15 a.m. Eastern and Jerome Powell at 12:40 p.m. Eastern.

The stat

$2 billion. That's how much fraudulent returns will cost retailers over the holiday shopping rush, according to the National Retail Federation (http://www.businessinsider.com/holiday-shopping-fraud-cost-2-billion-dollars-2016-11).

Adobe says its final tally shows $3.39 billion was spent on Cyber Monday -- a record and a 10.2% rise on a year ago.

Random reads

5 survivors, more than 70 dead after plane crashes in Colombia. On board, a beloved Brazilian "Cinderella" soccer team (https://apnews.com/afa4c77206294384991e4f53c7e93680/Colombia-authorities-say-they-are-responding-to-plane-crash). (http://www.bbc.co.uk/news/world-latin-america-38140981?ns_mchannel=social&ns_campaign=bbc_breaking&ns_source=twitter&ns_linkname=news_central)

Are options a mystery to you? This explainer from Slope of Hope is great (http://slopeofhope.com/2016/11/building-blocks-by-the-director.html).

(http://www.bbc.co.uk/news/world-latin-america-38140981?ns_mchannel=social&ns_campaign=bbc_breaking&ns_source=twitter&ns_linkname=news_central)Evacuations under way in Gatlinburg, other tourist spots due to Smoky Mountains wildfires (http://www.nbcnews.com/news/us-news/tennessee-mountain-resorts-gatlinburg-pigeon-forge-evacuated-wildfires-n689396)

(https://twitter.com/kingofkingsport/status/803464455157936129)

Happy 117th to Emma Morano, the last living person born in the 1800s (http://www.bbc.co.uk/news/world-europe-38141440?ocid=socialflow_twitter)

Thailand's Prince Maha Vajiralongkorn set to be crowned King Rama V (http://www.reuters.com/article/us-thailand-king-succession-idUSKBN13O05L?il=0)

More fodder for the Brexit unhappy:

(https://twitter.com/bridiepjones/status/803298570434646016)

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(END) Dow Jones Newswires

November 29, 2016 07:28 ET (12:28 GMT)

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