From the Spaceflight Meteorology Group:

The National Weather Service has issued a Tornado Watch that includes JSC, Ellington Field and Sonny Carter Training Facility until 3PM CDT.

Showers and thunderstorms are expected to increase in coverage this morning across southeast Texas a few of which could become severe.  An isolated tornado, strong gusty winds, brief heavy rain and possibly some hail are possible during the watch period.  Chances for tornadoes appear to better nearer to the Gulf beaches but cannot be ruled out near JSC and Ellington Field, particularly between noon and 2:30 PM.  The storms should be clearing out of JSC after 3:00 PM today.