The storms that recently covered parts of the U.S. with snow won't be enough to ease the nation's drought.

In fact, climatologists say, it would take historic snowfalls - an absurd amount, really - to undo the damage inflicted by 1 of the driest years on record.

Tom Schwarz understands that all too well. He believes it would take 150 inches to get the soil on his 750-acre Nebraska farm back to its pre-drought condition in time for spring planting. That's unlikely to happen in an area that usually gets about 30 inches per winter.

Climatologists say Schwarz's estimate isn't far off, in part because it takes about a foot of snow, depending on density, to equal an inch of water.