Weather's impact clouds Friday's jobs report

• Rebound from December cold spell could mean strong gains
• But cold weather may again affect January totals
• Economists forecasting 185%2C000 job gains

Predicting Friday's Labor Department tally of U.S. job growth in January is turning out to be as tricky as forecasting winter weather in Florida.

Many economists believe bad weather severely crimped employment totals in December as some workers stayed home, leading the analysts to expect a big pickup in January as those employees returned to the workplace.

Others say cold, stormy weather again held down job growth in January.

"It's hard to get a read on what's happening," says UBS economist Drew Matus.

Many investors are anticipating Friday's report after financial turmoil in emerging markets and recent weak economic data sharply drove down stock markets the past few weeks.

Private payroll processor ADP may have added to the confusing signals with its report Wednesday that businesses added 175,000 jobs in January, slightly below forecasts. Inclement weather "continued to weigh on the job numbers," said Mark Zandi, chief economist of Moody's Analytics, which helps ADP compile the survey.

The 175,000 total is below ADP's estimated 227,000 private-sector job gains in December. But it's well above the 87,000 private-sector gains and 74,000 overall additions (including government) reported by Labor for December. That marked a sharp drop-off from average monthly gains of more than 200,000 since August. ADP's reported increases have outpaced Labor's by an average 36,000 the past six months, according to an analysis by Barclays.

Jim O'Sullivan, chief U.S. economist of High Frequency Economics, says Labor's survey is far more sensitive to weather effects. He's looking for Labor to report 220,000 payroll gains in January, saying the weather-related rebound from December will far outweigh any additional weather impacts in January.

Matus generally agrees but is figuring in somewhat stronger negative weather effects last month. He forecasts 200,000 job gains.

Meanwhile, 21 economists surveyed by Action Economics estimate 185,000 jobs were added last month, according to their median forecast. What's unusual is that the predictions were clustered toward the low of 130,000 and high of 225,000, rather than being fairly evenly distributed, says economist Kim Rupert of Action Economics.

That, she says, indicates most economists are either looking for a strong bounce-back from December's weather-tinged weakness or continued weather impacts last month.

Excluding weather effects, Matus says, the labor market is poised to add 175,000 to 200,000 jobs a month this year as economic growth surpasses 3% for the first time in the nearly 5-year-old recovery. The private sector, aided by an accelerating housing recovery and lower household debt, is expected to strengthen.

This week, a measure of manufacturing activity showed a far more modest expansion in January, with economists citing weather as a main factor. An index of service-sector activity, which is less affected by weather, rose solidly and beat estimates.