A shift to higher borrowing costs is probably months away, but Fed chairman Ben S. Bernanke and his colleagues likely will privately debate how best to signal a change in stance to investors, businesses and ordinary Americans when they open a two-day meeting today.

After a record four straight losing quarters, the economy started growing again in summer quarter, although most of the fuel came from government-supported spending on homes and cars.

Despite the turnaround, growth won't be sufficient to prevent the unemployment rate - now at a 26-year high of 9.8 percent - from rising. Economists predict it will hit 9.9 percent when the government releases the latest snapshot on employment conditions on Friday. It's expected to top 10 percent this year.

Rising unemployment, cautious consumers, tight credit and troubles in the commercial real-estate market are among the forces expected to weigh on the recovery going forward.

Against that backdrop, most economists think that when the Fed concludes its meeting tomorrow, it will keep the target range for its bank lending rate at zero to 0.25 percent. If it does, commercial banks' prime lending rate, used to peg rates on home equity loans, certain credit cards and other consumer loans, will stay at about 3.25 percent, the lowest in decades.

"The Fed has some glide time right now to see where the economy is going," said Wells Fargo's chief economist John Silvia.

For now, Silvia and other economists also predict Fed policymakers will maintain a pledge to keep rates "exceptionally low" for an "extended period" to make sure the recovery gains traction. The Fed has leeway to do so because inflation thus far has been low, economists said.

Low rates encourage borrowing by businesses and individuals - and thus boost economic activity.

Whenever the Fed decides to drop its "extended period" language, it will be taken as a signal that the central bank is preparing to reverse course. Many analysts think the Fed could start to raise rates in the spring or summer.

Given the delicate state of the recovery, Bernanke made clear last month that he's in no rush to boost rates and reel in the unprecedented amount of money the Fed has plowed into the economy. Other Fed policymakers, however, have suggested that rates might have to go up sooner rather than later.

"If policymakers insist on waiting until the level of real activity has plainly and substantially returned to normal - and the economy has returned to self-sustaining trend growth - they will almost certainly have waited too long," Fed Governor Kevin Warsh warned in a speech just days after the Fed's Sept. 22-23 meeting.

It promises to be a high-wire act for the Fed. Boosting rates and removing supports too soon could short circuit the recovery, while holding rates low and keep supports intact for too long could unleash inflation.