From the Spaceflight Meteorology Group

The National Weather Service has issued a Severe Thunderstorm Watch that includes Galveston County until 8PM CDT this evening. Technically JSC and Harris county are not in the watch area. A cold front merging with a sea breeze is expected to force increased thunderstorm development this afternoon and evening. Storm should weaken by late evening.

A few of these storms could become severe with hail and strong winds.  Hail up to 1.5 to 2.0 inches in diameter looks to be the largest threat followed by wind gusts up to 70 mph. Rainfall amounts through tomorrow morning should average around 0.5 to 1.0 inch around JSC with stronger storms possibly bringing up to 2 inches.