Wednesday, December 23, 2009
Tornadoes possible today...flurries possible tomorrow
A strong storm system will finally move into East Texas today and with it, a threat for severe weather, including tornadoes. Out ahead of this system, very moist air from the Gulf of Mexico is surging north across the Lone Start State. We are even seeing a few breaks in the clouds this morning and that could lead to extra instability this afternoon.
Winds out ahead of this system this afternoon will increase out of the southeast around 18 mph gusting as high as 25 mph. This will help set the stage for the turning of wind with height that could lead to tornado development this afternoon and evening. The greatest risk of tornadoes appears to be from Tyler to Longview to Marshall and points south from 4PM through the overnight hours.
Scattered thunderstorms will develop ahead of the cold front during this time and it will be these scattered storms with the best chance to rotate. A strong line of storms will develop late tonight around the Metroplex and race east early tomorrow morning. Along this line we will see the possibility of strong winds and even an isolated tornado, although the tornado threat will not be as high as it will with any discreet storm this afternoon and evening.
After this strong line of storms move through, very cold air will rush in tomorrow. Many of our forecast models are now indicating all the moisture may not be out of the area before the cold air moves in, especially north of I-20. What does this mean? It means there is a chance areas north of I-20 could see a few snow flurries.
The light blue around the I-20 and I-30 corridors is light snow that could eb falling tomorrow afternoon.
It all depends on the exact track of the upper low pressure system tomorrow. If this system moves farther south, the chance of snow could move into the Tyler and Longview areas however, no accumulation is anticipated at this time. Right now it does appear there could be a light accumulation north of I-30 and if you are planning travel into Oklahoma, several inches of snow could accumulate tomorrow.