Obama administration officials said Monday that some visitors to HealthCare.gov will experience outages, slow response times or try-again-later messages in December.

The Centers for Medicare and Medicaid Services (CMS) delivered the message in the latest attempt to downplay expectations for Nov. 30, the administration’s self-imposed deadline for fixing ObamaCare’s federal enrollment site.

{mosads}CMS spokeswoman Julie Bataille said errors that persist past this weekend would be “intermittent” and, in line with a promise made by the White House, would not affect the vast majority of the site’s users.

But Bataille acknowledged that some would still experience “periods of suboptimal performance” by the system due to either heavy traffic or technical issues that are still being addressed.

“The system will not work perfectly on Dec. 1, but it will work much better than it did in October,” Bataille said.

The comments came after HealthCare.gov experienced an unscheduled outage on Monday for one hour. The CMS had recently touted the site for not randomly crashing. Bataille said the problem was remedied quickly by the site’s tech team.

Administration officials are facing a challenge in how to describe the system’s status.

It’s clear from user reports that HealthCare.gov has improved substantially in the last month, and the administration is eager to tout their progress amid anecdotes about persistent errors.

But the site is still far from perfect and could remain problematic on and off for the foreseeable future.

The White House said Monday the repair effort is “on track” to meet the Saturday deadline thanks to steady technical improvements.

Seeking to strike a balance, spokesman Josh Earnest said the site remains a “work in progress” but touted metrics showing that its error rate and page load times are now far below where they started.

The administration has staked its healthcare rollout on expanding the system’s user capacity and addressing site errors by the end of the month, which falls over the Thanksgiving weekend.

Both supporters and opponents of the Affordable Care Act are closely watching the deadline, which helped the White House tamp down a political firestorm over the exchanges’ troubled debut.

The White House knows that if the site cannot recover by next month, its dysfunction will plunge the administration into another political crisis.

The month of October dealt a serious blow to President Obama’s poll numbers and erased Democrats’ political advantage coming out of the government shutdown.

Opponents see any further missteps on healthcare as crucial fodder for next year’s midterm elections.

Further technical problems at HealthCare.gov would also threaten the wave of enrollments expected in the first three weeks of December, putting consumers at risk of lacking coverage they need on Jan. 1.

Former White House budget director Jeff Zients, who is now in charge of fixing the healthcare site, said last week that the system would “reach everybody we need to reach” in December, thanks to ongoing fixes.

Part of that effort is building the system’s capacity to handle user traffic. HealthCare.gov was designed to handle 50,000 concurrent users but has only managed about half that number since Oct. 1.

The CMS said that, by this weekend, the site will be able to handle a full user load and will have a “queuing” system in place in case of traffic above that threshold. Under that program, users can either wait to be granted access or choose to receive an email when traffic dies down.

But not all parts of the system are working well, even two months after the exchanges launched.

HealthCare.gov has struggled to transmit accurate application information to insurance companies in forms known as 834s. The CMS did not provide an update Monday on that fix, suggesting that officials are still struggling to ensure the forms are correct.

The 834 issue highlights the range of problems that could arise for HealthCare.gov even if the site’s user experience improves.

The system relies on a series of complicated interactions with insurers as well as federal agencies to determine eligibility for premium tax credits and Medicaid.

Critics have charged that the broken system cannot be trusted to accurately make eligibility determinations. It is unclear whether this is a problem facing HealthCare.gov.

The Obama administration is also behind on launching its Spanish-language enrollment website and its online enrollment system for small businesses.

Bataille said that the small business sign-ups, now available only in paper form, would be “enhanced” by the end of the month, but did not say when the related Web system would be ready.