TORNADO WATCH UNTIL 10pm for areas along I-20 and north. Does include Dallas, Tarrant, Denton and Collin County. This is a PDS (Particularly Dangerous Situation) Tornado Watch. If you were to rank severity of tornado watches this would be the highest severity. The watch discussion talks of 3” hail and strong long-track tornadoes possible in the watch area.
After looking at the 18Z (1pm) sounding over Fort Worth, the atmosphere remains very strongly CAPPED here in the metroplex. That CAP is weakening out west where the upper level disturbance is arriving first. Storms have already developed in Oklahoma. We are seeing a storm develop now north of Abilene along the dryline in Texas. More storms will fire along that dryline this afternoon and move east. The coverage of these storms may not be very high. We may have only two or three supercells, but where they hit they will be quite severe.
3pm thru 6pm… Storms will be developing early in this period in western sections of North Texas west of Fort Worth. These will be large rotating thunderstorms with large hail and a tornado threat.
6pm thru 10pm… Storms will be moving into the mteroplex area. If the storms come together into a complex of storms, the tornado threat would be a little lower here in the metroplex. But if they say discrete supercells the tornado threat will still be high here.
10pm thru the night… storms will start to wane after 10pm, but likely still some stronger storms for areas from Dallas east for a few hours during the overnight hours.
Here is a nice map illustrating the severe threat for the region from the NWS.