They say you can never predict the weather with absolute accuracy, but if you have an old TV and get reception over the air in the City Different, a massive snowstorm is most certainly headed for your living room.

Unless Congress decides to stop it, that storm will come Feb. 17 at midnight. The only way to avoid it is if you've planned ahead and secured a digital TV converter box for your set.

If not, the snow will last, well, forever.

On Feb. 17, all TV stations using full-power broadcasts must stop sending analog over-the-air transmissions and switch to digital format.

In more rural areas, low-power TV stations and translators can continue to broadcast after that date, but eventually they, too, will have to make the switch.

And in Santa Fe and Albuquerque, those low-power broadcasts are not an option — meaning the 29 percent of over-the-air TV users in those cities that have yet to make the switch could very well be seeing snow on Feb. 18.

"The reason this is important is those viewers are generally from underserved populations, the elderly, the poor and rural viewers," said Polly Anderson, general manager and chief executive officer of KNME-TV, which as a public television station has been leading the effort to inform New Mexicans about the switch. "Those populations rely on their televisions for emergency information, and if they wait till the last minute and don't get their TVs set up, they'll see snow."

Television stations didn't decide to make the switchover themselves. The federal Digital Television Transmission and Public Safety Act of 2005 mandated them to make the change.

The reason is that digital TV transmissions take up a lot less space on the airwaves than analog ones do — and with growing use of cell phone and wireless communications, the government decided to switch TV to digital to save valuable and limited spectrum space.

The government also created a program through the National Telecommunications and Information Administration to help consumers pay for digital TV converter boxes for their old TV sets.

That program, which has been in effect for about a year, got $1.5 billion worth of funding, with a $1.34 billion allocation to give consumers up to two $40 coupons to offset the cost of the digital conversion boxes, which range from $40 to $80 retail.

The problem is, a few days ago, that money reached its cap. So they only way funds will free up for more coupons is if people that already have coupons don't use them, said Todd Sedmak, a spokesman for NTIA.

"There's a waiting list," Sedmak said, adding that people who add themselves to the waiting list will get coupons only if existing coupons aren't redeemed.

That said, though, "if people have received a coupon, we urge them to redeem it before it expires so they're ready for the conversion," Sedmak said.

In Santa Fe and Albuquerque, people have requested 264,000 coupons and redeemed 108,000 of those, but some of the coupons went to homes that don't rely solely on over-the-air transmissions. Those that use TV services like cable or satellite don't need to do anything, and their TV service will continue, Sedmak said.

And there are still 102,000 households in Santa Fe and Albuquerque that rely solely on over-the-air transmissions for TV service. Of those households, 85,000 have requested coupons — or 71 percent.

That puts the cities on the low side of being ready for the conversion, but they are far from dead last in the country, Sedmak said.

On an eight-page list of communities and their preparedness for the conversion, Santa Fe and Albuquerque, at 71 percent prepared, fall on the second to last page about half-way down.

The least prepared community in the country is Juneau, Alaska, with only 16 percent of its over-the-air households ready for the switch.

KNME has been trying to spread information for New Mexico viewers for the past year, Anderson said. But commercial stations haven't spent nearly as much airtime trying to let consumers know what's coming, because a lot of their commercial airtime was taken up by ads from the recent political campaigns, she said.

In September, the Federal Communications Commission did a test switchover in Wilmington, Del., complete with a media blitz on several stations, though, and even with all the advertising, there were still big problems after the town switched, Anderson said.

"They had thousands of people calling into to television stations after that test," Anderson said. "Even with a disproportionate amount of information, a lot of people waited until the last minute and didn't have anything set up."

KNME is expecting a similar rush of phone calls Feb. 18, and the station is trying to beef up its information lines and add more volunteers to take calls on that day, she said.

The station is also hosting an open house from 9 a.m. to 2 p.m. Saturday in Albuquerque, at 1130 University Blvd. N.E., where people can bring their sets in and ask experts how to set them up.

Station officials may also host one later in the month in Santa Fe, but nothing has been planned yet, Anderson said.

And if you're a gear head or at least somewhat technology savvy, you shouldn't have much problem setting up a converter box yourself. The boxes are set up through video in and video out connections between an antenna and a VCR or television.

"People who are comfortable in the computer age should have no problem," Anderson said. "But lower income groups, the elderly, some others might have difficulty."

People in nursing homes, who have over-the-air TVs in their rooms, could be especially hard hit by the transition, she added. "For many of them, that's their window to the outside world, and it may be going away," Anderson said.

Some church groups in both cities have been trying to organize missions to help the less technologically savvy through the process, although there is no formal list of any of them, Anderson said.

If money isn't a problem, TV repair services like Coca's TV Service in Santa Fe can come out and hook your old set up for you, said owner Emilio Sanchez. "Usually these hookups take about 5 to 10 minutes, and we can certainly do that for people," he said.

The cost is about $45 and it can be done during a normal service visit, he added.

The conversion might be an annoyance for consumers, but it does come with its benefits. After switching to the digital box, TV viewers will see a much cleaner picture and have access to additional stations in some cases.

KNME, for instance, will provide access to four stations through its digital stream. They are: KNME 5.1, which will have core PBS programming, KNME 5.2, which will feature programming in Spanish, KNME 9.1, which will have mainly science documentaries and current affairs programs, and KNME 9.2, which will feature instructional programs on cooking, gardening, home improvement and other areas.

And some of those feeds won't be available to people who use cable or satellite for their service, Anderson said, giving over-the-air viewers some fodder to thumb their noses at all those pay subscribers out there.

"With the digital box you'll probably also need to have an antenna, but the bonus is that the picture is great, you get more services, and it's over the air, so it's free," Anderson said.

Contact Sue Vorenberg at svorenberg@sfnewmexican.com.

GET READY FOR THE DIGITAL SWITCHOVER

• For more information on the digital TV switchover, visit www.dtv2009.gov or www.knme.org. You can also call KNME-TV toll free at 877-388-5663.

• KNME is also hosting an open house from 9 a.m. to 2 p.m. Saturday in Albuquerque to provide hands-on help for those making the switch. To participate, visit the studio at 1130 University Blvd. N.E.