2012 is shaping up to be warmest year on record in Texas

Barring a late December cold snap, North Texas is on track to have its warmest year on record.

Through Wednesday, the average temperature this year was 69.9 degrees, 0.6 degree higher than in 2006, currently the warmest year.

Earlier this month, the National Oceanic and Atmospheric Administration said 2012 was "likely" to be the warmest year on record for the Continental U.S. based on weather data through the end of November.

While it has been above normal most of the year locally, it was the first half that was unusually warm.

At Dallas/Fort Worth Airport, March was 6.7 degrees above normal, April was 4.8 degrees above normal, and January was 4.5 degrees above normal.

National Weather Service meteorologist Joe Harris said the higher temperatures during the first half of 2012 could probably be attributed to the influence of La Niña, the condition in the Pacific Ocean that tends to bring warmer winter temperatures to Texas.

"I think you can say with the exception of one or two months that the entire year has been above normal, but the first half of the year was exceptionally warm," Harris said. "The La Niña effect began to wane considerably during the summer."

Warm weather has been the trend in recent years, with the six warmest years on record having occurred since 1998.

State climatologist John Nielsen-Gammon said global warming isn't to blame but pointed to warm cycles in the Atlantic and Pacific oceans that began in the mid-1990s and typically last 20 to 25 years.

Drought persists

While temperatures have been warm this year, the biggest impact has been the return of the drought across North Texas.

Even though the Dallas-Fort Worth area saw periods of wet weather earlier this year, the drought never really went away for most of Texas, Nielsen-Gammon said.

"Texas really hasn't been out of a drought since 2011," Nielsen-Gammon said. "There hasn't been a time since then when half of the state was drought-free."

In the latest state drought monitor released last week, 65 percent of the state was in severe drought, up from 59 percent a week earlier.

The amount of the state classified as extreme drought, including a swath of North Texas just to the west and south of the Metroplex, grew to 32 percent, up from 27 percent a week earlier.

At DFW Airport, rainfall is about 7 inches below normal since Oct. 1.

"October and November are the second-driest on record for Texas," Nielsen-Gammon said. "So far, we haven't seen enough in December to reverse that trend."

Water restrictions near

As the drought continues to worsen in Texas, it's close to ushering a return of outdoor water restrictions.

The Tarrant Regional Water District, which supplies raw water to 98 percent of Tarrant County and 1.8 million people in North Texas, is currently projecting that Stage 1 outdoor water restrictions will go into effect around the second week of January. Those restrictions are triggered when the water supply drops to 75 percent. As of Friday, it was 78 percent.

The restrictions could be further delayed by some rainfall, but it would take an enormous amount of rain to avoid restrictions.

Six to 9 inches of rain would be needed to refill area lakes over the next three months, said David Marshall, Tarrant Regional's engineering services director.

"It's highly unlikely we're going to recover this winter," Marshall said. "We've had such an incredibly dry October and November. The evaporation rates in early December were more like September."

Mary Gugliuzza, a spokeswoman for the Fort Worth Water Department, said it plans to meet with wholesale water customers to bring them up to date on the expected return of water restrictions.

"I think it's not a matter of if but when it will happen," Gugliuzza said. "The only thing we don't know is the exact date those restrictions will be triggered."

Bill Hanna, 817-390-7698

Twitter: @fwhanna

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