Low water levels in streams and groundwater reservoirs amid cold weather are evidence of a "hidden drought," whose true impacts will be apparent next spring.

Water reservoirs, stock ponds and underground aquifers, especially in the Southeast, are depleted in a time when the late fall weather should be recharging them, said Eric Luebehusen, a climatologist with the Agriculture Department and author of this week's Drought Monitor. The Southeast's area covered in moderate-to-exceptional drought increased by nearly 52 percent in the past week, despite cooler-than-normal weather.

Because most of the year's crops have been harvested and municipal water use is lower, residents of the region may not see the drastic results of the drought until next year.

"Wintertime drought is always difficult for us to quantify," Luebehusen said. "The immediate 'wow' impacts aren't as pronounced."

Although it is not noticeable from the weather, "it's kind of going on right beneath your feet," said Mark Svoboda, a climatologist with the National Drought Mitigation Center at the University of Nebraska, Lincoln.

Overall, temperatures have remained normal or below normal east of the Mississippi River, according to the Drought Monitor. This is also the driest time of year for most of the area east of the Mississippi and the Rockies, Svoboda said.

"Those impacts will be ready to emerge first thing in the spring," he said. Because the cool weather keeps the evaporation rate low, even a little moisture can go a long way in the dry winter.

"That's the time you can have the most effective recovery from drought," he said.

Now you don't see it (but you will)

Last winter, the Great Plains states were afflicted with drought as the cold rolled in, but farmers were fortunate enough to save the winter wheat crop with a few well-timed rains. This year, farmers are worried that good luck may not strike twice (ClimateWire, Nov. 26).

Although no weather event can be linked directly to climate change, the length and intensity of this year's drought, along with Superstorm Sandy, has rekindled the discussion of adapting to a future of weird weather.

A good snowpack this winter will be critical for ensuring the recharge of groundwater aquifers and streams, Svoboda said, in the East as well as in the Rockies. Hopes for a wet El Niño weather pattern have fizzled, as the Midwest and Southeast drought zones remain in a neutral weather pattern.

With the exception of west-central Alabama, rainfall over the past two months has been less than 50 percent than normal. Stream flows from the Carolinas to northern Florida are in the bottom fifth percentile, according to the Drought Monitor.

Although a low water table may not affect plants and landscapes in the first months out of winter dormancy, the effects will come soon after, Luebehusen said. "Initially they grow fine," he said of vegetation. "In a month or two, if you haven't seen any recent rainfall, then you start to see it."

Stream flows around the Vermont-New Hampshire border and southern Virginia are rapidly declining while the weather remains cool.

The Apalachicola-Flint River Basin is especially low, said Georgia state climatologist Bill Murphey. The basin is an important supply of water for Georgia, Alabama and Florida and the cause of a tri-state dispute over the past two decades.

Murphey is looking forward to the possibility of some well-timed rains in the next few weeks, aided by weather patterns coming in from the Gulf of Mexico.

"We're hoping for several good precipitation events and a steady soaking rain for Georgia," he said.