This live blog was last updated early Friday morning.
On the southern side of a major winter storm, severe thunderstorms race eastward from Texas and Oklahoma to Alabama by later Thursday night.
Initially, large hail will be the main threat from storms through Thursday morning. During the day Thursday, the threat will evolve to include damaging winds and tornadoes.
AccuWeather.com meteorologist Anthony Sagliani details the timing and impacts of these storms.
1:10 a.m. CST Friday: For the moment, the severe threat has ended. However, thunderstorms can still drop heavy rain from southern Louisiana into Alabama. While there can be stronger storms again later Friday, the threat will shift from damaging winds to flooding downpours.
11:15 p.m. CST Thursday: Law enforcement reported a tornado northwest of Hattiesburg, Miss. at 10:34 p.m. CST. This storm is headed north of Hattiesburg and will cross I-59 shortly. A tornado threat remains across far southern Mississippi for the next few hours as thunderstorms rumble into the night.
7:57 p.m. CST Thursday: Numerous trees downed near the Sabine and San Augustine County line in Texas. Sabine County law enforcement reports that a 74-year-old woman was killed when a tree fell on her mobile home, causing the roof to collapse.
5:50 p.m. CST Thursday: Thunderstorm winds blew a roof off a house along Highway 65 near Clayton, La.
3:51 p.m. CST Thursday: A violent storm is passing near Alexandria, La. A possible tornado touch down has been reported in the area.
2:48 p.m. CST Thursday: Trees and power lines down in Cherokee County, Texas as a result of thunderstorm winds. Damage to residence and barn also reported.
2:05 p.m. CST Thursday: Sheriff in Tyler County, Texas reports wind gusts in excess of 60 miles per hour accompanied by hail. Trees also reported down in Polk County, Texas as a result of thunderstorm winds.
1:00 p.m. CST Thursday: The signs of severe weather are brewing in Louisiana and that may be the seed of our severe weather outbreak. The temperature and humidity are coming up enough that they could support tornados.
12:30 p.m. CST Thursday: More hail was reported in central Arkansas.
12:00 p.m. CST Thursday: According to FlightStats.com, severe weather delayed nearly 400 flights and cancelled over one hundred at the Dallas-Fort Worth Airport.
11:30 a.m. CST Thursday: The temperatures are still too low for the storms to really get going, which is not conducive to severe weather. Houston is getting more warm and humid.
10:10 a.m. CST Thursday: "I think we need to wait and see what happens when it gets over to Louisiana," AccuWeather Meteorologist Henry Margusity said. "That's where people need to watch, central and southern Louisiana."
9:50 a.m. CST Thursday: Half-dollar-sized hail reported in central Arkansas and quarter-sized hail reported in southern Arkansas.
8:50 a.m. CST Thursday: The line of storms that people need to watch just moved through Dallas. The storms caused heavy rain and wind gusts between 30 and 40 mph. The line is moving east and will cause problems, like damaging wind and hail, in its path. A tornado is not out of the question. The strongest storms will be this afternoon and evening over extreme eastern Texas and into Louisiana.
7:55 a.m. CST Thursday: "Severe weather over the next few hours is going to focus around College Station down to Houston," AccuWeather Meteorologist Henry Margusity said. "That is where the greatest inflow of moisture is right now."
6:20 a.m. CST Thursday: The line of thunderstorms will head into Dallas within the next hour. Torrential downpours may slow the morning commute. Hail and gusty winds are also possible.
3:25 a.m. CST Thursday: A line of thunderstorms has developed from just west of Wichita Falls to south of San Angelo and is pushing eastward. The area to the east in central Texas is being monitored for a possible tornado watch.
1:36 a.m. CST Thursday: While not uncommon, it isn't everyday that thunderstorms occur when it is in the mid 30s! This is exactly what is happening in Oklahoma this hour. Strong thunderstorms producing small hail are approaching Oklahoma City while thundersnow and "thundersleet" has been reported to the north and west.
11:25 p.m. CST Wednesday: Thunderstorms have erupted over the Texas Panhandle. The storms are expected to strengthen overnight as warm, moist air surges northward. Through the night, the main threat will be large hail. There is the potential for a severe thunderstorm watch to be issued early Thursday morning.
A new tropical threat may loom for the Caribbean and North America in the not-too-distant future, while eight more weeks remain in the Atlantic hurricane season.
The greatest danger of flooding across the central United States will unfold in western Texas, where downpours will be most persistent into Monday.
Fall air has finally arrived in the northeastern United States and may yield the first frost of the season in parts of the region this weekend.
Typhoon Megi will continue to strengthen before threatening lives and property across Taiwan and eastern China this week.
The first windstorm of the season could blast the northern United Kingdom around Tuesday of this coming week as Karl arrives.
Hot, dry and windy weather into Monday will lead to an increased risk of wildfires across Southern California.
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