From the Spaceflight Meteorology Group:

The National Hurricane Center has issued a Tropical Storm Watch for the JSC area.

At 4PM CDT, Tropical Storm Nicholas was located at 22.8 N 95.5 W or 465 miles south of JSC.  Nicholas was moving NNW at 14 MPH.  Maximum sustained winds were 40 MPH.

Nicholas is forecast to make landfall on the middle Texas coast, likely near Matagorda Bay late Monday night or Tuesday morning as a strong Tropical Storm or possibly a minimal hurricane. The primary threat to JSC appears to be the threat for heavy rain and possible flash flooding Tuesday morning. A Flash Flood Watch and Storm Surge Watch are also in effect for the JSC vicinity.  More precise details will be issued for JSC Monday morning.

The next advisory will be issued around 8:30 AM CDT Monday with another update later in the morning.

Tropical Weather Info from National Hurricane Center:
NHC Tropical Weather Page
Hurricane Statement from NWS Houston/Galveston:  Hurricane Statement from NWS