From the Spaceflight Meteorology Group:

The National Weather Service has issued an Areal Flood Advisory which includes JSC, NASA Ellington Field and Sonny Carter Training Facility through 4:15 PM this afternoon. A Tornado Watch remains in effect for JSC until 6PM today although the tornado threat is decreasing quickly now.

At 3PM 1.46 inches of rain has fallen at JSC Building 30 since midnight, about one ich of that in the past hour.  NASA Ellington Field has recorded 2.30 inches of rain.

The strong line of storms has moved east of both JSC and Ellington Field and the threat for severe weather has decreased substantially. Winds will remain breezy through the evening hours and we may see another 0.25 to 0.5 inch of rain so some minimal to minor street flooding and ponding of water on-site will continue for a short time.