For the past several months, there's been a heavy fog obscuring America's economy. Or, as top executives of public companies might say, there's been a real "lack of visibility."

Faced with such conditions, any reasonable investor would slam on the brakes, which is pretty much what has been happening to lending, investing and spending for months.

Now, as businesses try to move ahead without being able to see more than a few feet in front, they're talking about visibility, trying to get visibility and trying to help shareholders stay brave without much visibility. It's like a whole bunch of business meteorologists at work.

Listen to some of the conversations between corporate executives and the analysts who participate in their quarterly earnings conference calls:

"Our visibility remains rather low in the current environment, making our forecasting challenging, and we are therefore going to provide a broad range of revenue and earnings guidance for the March quarter," said Peter Oppenheimer, chief financial officer of computer seller Apple, in a January call discussing first quarter earnings.

"Given the continued uncertainty and the lack of visibility in the financial environment, we feel it is wise to refrain from issuing guidance for 2009," said Bankrate chief Thomas R. Evans, in an early February session. The company's stock price fell.

A month later, the business community was still waiting for some clearing.

"The lack of visibility into the next 10 months makes it very hard to provide earnings guidance for this year," said CEO Bill McComb, during clothier Liz Claiborne Inc.'s fourth quarter earnings chat with analysts in early March. The company did say it was assuming a year rather like the difficult fourth quarter of 2008.

And a week later: "Due to the lack of visibility created by the current economic environment, particularly in the back half of the year, we believe it is appropriate to provide estimates based on the continuation of trends from the fourth quarter of 2008 into fiscal 2009," said Edward W. Stack, chairman and CEO of Findlay retailer Dick's Sporting Goods.

The use of the term "visibility" in this fashion has been around for probably a decade, said Tony Rossi, senior vice president of Financial Relations Board, a company that specializes in financial communications and investor relations. He called the term part of the lexicon of Wall Street.

It tends to be heard more during downturns, he said. Back when technology companies were having trouble a few years ago, they talked a lot about visibility, and the lack of it. A few drove off embankments and cliffs hidden by the haze.

Mr. Rossi's organization surveyed sell-side analysts in late 2008 to answer questions from management teams trying to figure out how to handle the uncertainty in ways that wouldn't damage their stock or their credibility.

Or, as the Financial Relations Board described one question, "Should we continue to provide earnings guidance when we have limited visibility?"

The answer from those surveyed seemed pretty unequivocal. More than 75 percent of the analysts believed that the stock market would penalize companies that stopped issuing earnings guidance.

In a storm, especially, investors want to feel the management team isn't hunkered down and lost, said Mr. Rossi. In the long run, a company that offers as much information as possible about where things stand and what developments could blow things off course builds more trust.

"It's OK to disappoint the Street. It's not OK to surprise the Street," said Mr. Rossi, quoting an old saying.

In more stable times, he said most companies were pretty good at forecasting results. The rapid changes of the past few months have made predicting how many dresses shoppers will buy or how many airplanes a corporation may order rather difficult.

But there may be some forgiveness for those who do their best while allowing themselves a little more room on either side.

Many companies are using another communications tool to cope with the fact that they don't have a good sense of how products may sell in the next three months or in the next year, Mr. Rossi said. They're offering a wider range of projected earnings outcomes. Instead of projecting earnings per share within a few pennies, they may present a much broader guidance range.

Even that is better than nothing, he said. "You definitely do have other companies that are taking a 'let's hide under the desk' mentality."

The market will remember, Mr. Rossi said.

When things get better and the sun shines again on the global economy, investors won't forget the management teams that can be trusted to drive carefully even when the windshield is all fogged up -- and to admit they're not entirely sure what's coming around the next bend.