Why such a winter? It's hard to say

By Errol Castens/NEMS Daily Journal

UPDATES 7:49 a.m.: JACKSON – The Mississippi Department of Transportation (MDOT) announces slick roadway conditions for motorists traveling in northeast Mississippi.

Overnight wintry weather moved across the northern part of the state leaving ice on bridges in Alcorn, Prentiss, Tippah and Tishomingo counties. Motorists are urged to drive with extreme caution if you are traveling in the area, especially over bridges and overpasses.

MDOT personnel will be monitoring the weather and will take whatever measures necessary to keep Mississippi roadways safe. Motorists are encouraged to buckle up, drive safely, stay alert and slow down, especially when driving in wintry weather conditions. MDOT will keep motorists posted on road conditions as information becomes available.

For the most up-to-date information in your area, please visit www.MSTraffic.com and sign up for your traffic alerts. Also, visit http://www.mstraffic.com/mobile to get the latest traffic information from MSTraffic.com on your mobile device. MDOT advises the public to pull off the road to a safe location if you need to check the MSTraffic.com website while driving.

Story from this morning’s NEMS Daily Journal newspaper.

OXFORD – The 2010-11 record-setting “winter of snows” in Northeast Mississippi began with trace amounts on Dec. 12 and 18, followed by much of the region’s waking up to a white Christmas.
It peaked on Jan. 9-10 with the biggest snowfall in some places in at least two decades – as much as 11 inches reported in Benton County. A third snowfall on Jan. 20-21 spread a light blanket on some of the region.
Tuesday night’s forecast included the likelihood of snow across the entire region – two to four inches in many counties, with a narrow belt starting near Holly Springs facing a possibility of as much as eight inches.
It’s a dramatic change for Northeast Mississippians, who only occasionally see snow that sticks long enough to take a picture.
“There’s no date for which snow is ‘normal’ in Tupelo,” said Memphis-based National Weather Service forecaster Marlene Mickelson.
The season is considerably colder, too. December temperatures in Tupelo averaged 3.5 degrees lower than normal, and 4.8 degrees colder thus far in January.
“It’s hard to say why this winter is so different,” said Andy Sniezak, another NWS Memphis forecaster. “We’re in a La Nina pattern – that probably has something to do with it.”
But even La Nina is defying the usual definitions.
El Nino, a weather pattern characterized by unusually warm water west of Ecuador, Colombia and Peru, shares a common Latin American nickname for the Christ Child, because El Nino often appears around Christmas.
“La Nina the opposite of El Nino, brings colder than usual water to the eastern equatorial Pacific. Each pattern typically affects winter weather in various parts of the United States in predictable ways.
Not this year, though: According to the NWS, Tupelo has set or matched eight records for either the date’s lowest temperature, lowest maximum or greatest snowfall. (Even on some December and January dates, however, a trace of snow can be a record amount.)
“La Nina winters are usually warmer than usual in the Southeast,” he said, yet the very fact that forecasters were 3-for-3 in predicting the earlier snows could be attributed to colder conditions. Typically, snows are hard to predict in this region because a slight variation in temperature can change it to sleet, freezing rain or just rain.
“Most of the time (this winter) it’s been cold enough that there’s less of a question of whether it’ll be snow or rain,” Sniezak said. “Most times this winter it’s been cold enough that we knew for sure it was going to be snow.”
Yesterday, expectations of temperatures just a bit under freezing made the snow forecast “trickier,” he said.
Tupelo’s record winter snow, in 1935-36, was just shy of 12 inches, Sniezak said. So far this winter, accumulations at the weather station had totaled 8.2 inches through Tuesday.
The Memphis forecaster said the outlook for the rest of the winter is unclear, but Mike Pigott, a meteorologist for Pennsylvania-based Accuweather.com, said the unusual weather could continue in the Southeast.
“The jet stream pattern is oscillating somewhat,” Pigott said, “but it does look like it will lead mainly to colder than normal temperatures in the Southeast through February.”
Accuweather.com also predicts that this winter could be the coldest since the 1980s.
Contact Errol Castens at (662) 281-1069 or errol.castens@djournal.com.

Region sees rain, snow
- Temperatures dropped and the region saw a mix of rain and snow in the overnight hours going into today.
At press time Tuesday night, the Mississippi Department of Transportation was reporting icy accumulation on bridges, overpasses and sections of roadways in Tunica, DeSoto, Marshall and Benton counties.
According to the National Weather Service in Memphis, a winter storm warning began Tuesday evening and was set to be lifted at 6 a.m. today. A meteorologist in Memphis reported at 9:30 p.m. there was a mix of rain and snow in Tishomingo and Alcorn counties and light snow in Corinth. Areas south of that were mainly seeing rain.
The NWS reported overnight temperatures were expected to be around freezing and should warm up to the 40s today.

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