A small, but vigorous storm system in northwest Mexico will dig toward Monterrey tonight, then hook hard left through West Texas up into the Plains at midweek.  While in Mexico, the storm system will pull in a huge plume of Gulf moisture, resulting in big rains across much of Texas, including a possibility of severe storms southeast of DFW Tuesday night through Wednesday afternoon. 
Expect 1-3" of rain across DFW Tuesday, ending late Wednesday. 
We'll clear out and warm up Thursday and Friday. 
A new and stronger cold front is expected to plunge thorugh North Texas sometime Saturday, and at this time, we cannot rule out wintry precipitation on Sunday, January 13. 

- - Chief Meteorologist Brad Barton