This week offers key reports on the US jobs market including the ADP employment report on Wednesday, weekly jobless claims on Thursday, and the government's nonfarm payrolls on Friday.
"Any sense of weakness in the payroll number or any of the employment statistics we get [this] week would really be a cause for concern," Ellenberger noted.
Friday's Labor Department report is expected to show employers hired fewer workers in January than a month earlier, when payrolls jumped by almost 300,000, while the unemployment rate held at 5 per cent and hourly earnings rebounded, according to a Bloomberg poll.
Last week a bounce in oil prices - Brent rose nearly 8 per cent while US crude gained more than 4 per cent-amid talk of a potential coordinated effort by Russia and Saudi Arabia to cut production helped equity markets too, including Wall Street.
On Friday, the Dow Jones Industrial Average rallied 2.5 per cent, as did the Standard & Poor's 500 Index, while the Nasdaq Composite Index climbed 2.4 per cent, bolstered by the Bank of Japan's surprise move on stimulus as well as strong corporate results such as from Microsoft.
For the week, the Dow rose 2.3 per cent, while the S&P 500 gained 1.8 per cent, and the Nasdaq advanced 0.5 per cent.
Even so, the S&P 500 ended January with a 5.1 per cent slide for the month. That's the worst January for equities in seven years, according to Bloomberg.
"The question is: Do we get it all washed out in January and then move on, or is it a harbinger of doom to come? I don't know if I have a great answer either way," Gina Martin Adams, equity strategist at Wells Fargo Securities, told Bloomberg.
"A significant portion of upside equity returns usually do happen in November, December and January, so to lose the performance in January puts pressure on later this year," Adams noted.
Companies slated to release their latest earnings include Exxon Mobil, General Motors, Pfizer, Merck, Aetna, and Alphabet.
"For the past two quarters Alphabet has delivered strong results beating analysts' estimates," Peter Garnry, head of equity strategy at Saxo Bank in Copenhagen, told Reuters. "Facebook's blowout fourth-quarter results point to strong mobile and video numbers for Google."
In Europe, the Stoxx 600 Index posted a 2.2 per cent increase on Friday. That limited its slide for the month of January to 6.4 per cent.
Here, a meeting of Bank of England policy makers on Thursday will be eyed for clues on interest rates, as they present their latest forecasts for economic growth and inflation.
"The BoJ is the latest surprise but the [European Central Bank] were also dovish, and following some of the commentary from the BoE they're seen as likely to present quite a dovish Quarterly Inflation Report," Jason Simpson, a strategist at Societe Generale in London, told Bloomberg. Also, "turmoil in risk assets-commodities, oil, emerging markets etc-is seen pushing money into safe assets."