Not again! Another reason to cut Q1 growth?

International trade data Thursday could provide a deeper look at the strong dollar's impact on the economy in the first quarter and may result in economists again slashing growth forecasts.

Trade is released at 8:30 a.m. ET, the same time as weekly jobless claims. Factory orders for February are reported at 10 a.m.

The consensus forecast puts February's trade gap at $41.5 billion from $41.8 billion in January, but economists say there's a good chance the number could come up short. In January, the gap narrowed as oil imports fell, creating the lowest deficit for petroleum products in years. But economists this month are focused on whether exports are weakening due to dollar strength.

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Traders work on the floor of the New York Stock Exchange, April 1, 2015.
Richard Drew | AP Photo
Traders work on the floor of the New York Stock Exchange, April 1, 2015.

"That'll be a good window into how significant the dollar effects are up to this point…. I wouldn't be surprised to see if we go north of $45 billion," said Mark Zandi, chief economist at Moody's Analytics. "It's going to widen. We're heading toward a $50 billion trade deficit in the not-too-distant future. This is the biggest drag on growth."

The dollar index gained about 9 percent since the beginning of the year. Zandi said the effects of the rising dollar are becoming more obvious and exports will continue to be a weak spot in the economy.

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"GDP in Q1 is tracking around 0.7 of a percent," he said. "My guess is it's going to come in closer to 1.5 percent. Most of the data we've had so far is February, and February is a really bad month…. March is going to be a better month."

Economists also expect a spring back in the second quarter when the impact of cold winter weather on consumption fades. Economists expect second-quarter growth of more than 3 percent.

Forecasts for first-quarter growth were cut after weaker consumption and durable goods data last week, but Barclays raised its GDP tracking forecast Wednesday by 0.1 percentage point to 1.1 percent after auto sales for March came in at a stronger-than-expected selling rate of 17.15 million.

Stocks sank and bond yields edged lower Wednesday after the ADP data. The ISM manufacturing survey was also weaker than expected, and the employment component and new orders were also lower. ADP reported just 189,000 jobs in March, well below the 225,000 expected.

It now raises the risk that Friday's government employment report could be weaker than the 245,000 jobs expected.

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The ADP number rattled the markets since it was the first big monthly jobs report to show that the chilling of growth in the first quarter may also be affecting hiring. The Dow closed down 77 at 7,698, and the S&P 500 fell 8 to 2059. The 10-year yield fell to 1.85 percent in late trading.

Zane Brown, fixed income strategist at Lord Abbett, said the ADP report showed a clear weakening due to the stronger dollar, and that could show up in Friday's report for March employment. Brown said ADP added only 5,000 goods-producing jobs, compared with a recent average of more than 30,000.

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"It also corresponds with a pretty significant drop in jobs at large companies," he said, noting they added 19,000 jobs compared with more than 50,000 in recent months.

"Really, the large companies that are producing goods, it really suggests that the dollar is influencing their willingness to hire as well as earnings," he said. "If this really is a function of manufacturing at large companies and it really is a function of a dollar impact, then it could affect the Friday number as well."