The Lowcountry is teetering on having the driest winter since record-keeping began.

Even worse, records by decade indicate the region has been consistently drier for the last half-century than it was for a century before that.

The droughts that have recurred for the last 10 years are a problem, said Hope Mizzell, state climatologist.

"But I think you're staring at a much greater problem."

The wettest decade on record was in the late 1800s, when city of Charleston rainfall averaged more than 55 inches per year, according to S.C. Climatology Office graphing of city of Charleston records. Since 1973, the city of Charleston has averaged little more than 44 inches per year.

While the trend by decade is disturbing, the numbers don't necessarily signal a climatic shift. Both winter and summer rainfall patterns are a little drier, not a lot, said Cary Mock, a University of South Carolina associate geography professor who has studied climate trends.

"It's not like we're clearly getting to a drier climate."

But the relatively drier seasons coupled with warming temperatures would bring on more droughts, he said.

Longtime Johns Island farmer Sidi Limehouse has watched it happen.

"I can remember when water never got out of the ditches, the canals. The canals are now bone dry," he said. The Lowcountry always has cycled between wet years and dry years, but "the wet cycle is drier than it was, and the dry cycle is even drier." It used to be you could dig an irrigation well 20 feet down for water. That water might still be there, but you can't rely on it. He digs 40 feet now.

The long-soaking winter rains that farmers depend on to grow crops are evaporating. More and more, it's "dust settlers," in Limehouse's words -- just enough rain to wet the ground. When a tropical storm passed offshore in the summer, it dropped 8 inches of rain on the Limehouse farm -- the sort of soaking that used to leave the ground mucky for a while. Everything was under water, he said, "and the next day, it was gone."

Through Wednesday, the official Charleston rainfall since Dec. 1 was only 1.34 inches, more than 8 inches below normal for the December-February period considered to be meteorological winter, according to the National Weather Service, Charleston and the S.C. Climatology Office. Because a significant rainfall is forecast this weekend, it's likely this year won't become the worst on record, which was 1.83 inches in 1949-50.

But the next-lowest "winter" rain record was 2.54 inches, set in 1946-47, so this year is most likely to be at least the second-worst.

The oddest part might be that it hasn't seemed so dry. Unlike the drought years a few years back, when dry days would run end-to-end for weeks, rain has fallen. But there have been only 12 days of measured rain, Mizzell said.

And while Lowcountry streams such as the Edisto and Black rivers are considered to be in extreme drought, the Marion-Moultrie lakes are virtually full. The lakes are fed by streams with their headwaters in the Upstate and North Carolina, where rainfall is closer to normal; the rivers headwater in the Midlands.

The Lowcountry has been in some stage of drought for nearly a year, before groundwater completely recovered from a 2007 drought so severe that docks were stranded around Lake Moultrie.

The lakes are "right on the money for where we want them this time of year," said Mollie Gore, spokeswoman for Santee Cooper, the utility that manages the lakes. "We're keeping our fingers crossed right now."

Reach Bo Petersen at 937-5744 or follow him on Twitter at @bopete.