NASHVILLE (AP) -- National Weather Service forecaster Ryan Husted looked at his radar display and saw something he had never seen before -- snow and rain.

Where Husted had previously seen only a radar reflection of precipitation, on that recent day he saw that it was raining in Memphis, but snowing a few miles north in Millington.

The difference was the dual polarization technology that has been operational for about a month at the Memphis NWS forecast office.

Rain looks like pancakes on radar, Husted said. Snow looks like really big pancakes because of the melting layer. This time of year, all precipitation begins aloft frozen and melts, or doesn't, on the way to the surface.

The technological enhancement is being installed at the Old Hickory NWS office that serves Middle Tennessee beginning Jan. 16 and will be added to the Morristown forecast office that serves East Tennessee during the early part of February.

Nearly all NWS radar sites will have the upgrade by the end of 2012, said Tom Johnstone, warning coordination meteorologist for the Nashville office.

"It's going to give us a much better view, rain to snow, across the forecast area," Johnstone said.

While that difference is important, another capability of the dual polarizing radar is vital.

The enhancement will give forecasters the ability to see flying debris and know when a tornado has touched down.

Until the dual polarization (or "dual pol"), the image was of winds moving toward and away from the radar.

Rotation was evident, but there was no indication whether a tornado had struck or the radar was seeing a funnel cloud aloft.

Tim Van Horn, midday forecaster on WMC-TV in Memphis, agrees.

He has noticed slight differences out of the Memphis NWS office already, but said the upgrade's value will be proved in coming months.

"The biggest difference will come for us in the springtime when severe weather hits," Van Horn said.

"Anything that gives them [NWS meteorologists] a little extra time and a little extra information to pull the trigger on warnings will benefit everyone."

"It's like being a doctor's office," Van Horn added. "The more technology, the quicker the diagnosis."

Johnstone described the new radar as getting two views where only one was seen before.

Forecasters will now get both horizontal and vertical views where they only received a horizontal look previously. And the difference can be astounding.

"Within 50-60 miles of the radar site, we can see leaves and twigs [in the air]," Johnstone said. "It will improve warnings downstream of a touchdown."

Larger debris will be visible even farther out and upward for several thousand feet, he said.

The new system was tested for three years in the heart of Tornado Alley at Norman, Okla., before NWS decided to deploy it across the country.

"There was one event May 10, 2010, in which Norman could see six different tornadoes and all on the ground," Husted recalled from training.

Eventually, the enhanced information will be available to everyone at the NWS Facebook page and on the agency's website.

That will occur in 2013 after all radar sites have been upgraded, Johnstone said.

An additional advantage of the upgrade is a better ability to determine how much precipitation is falling and has fallen.

"This lets us make better forecast and warning decisions," Johnstone said.

Johnstone said it's just one more tool that lets a professional meteorologist look deeper into storms but it doesn't replace the human factor.

"The meteorologist has to be thinking about all this information," he said. "You've got to make some intuitive judgments."