From the Spaceflight Meteorology Group:

A Winter Storm Warning will be in effect for JSC beginning 6PM Monday night though 6PM Tuesday. In addition freezing temperatures for 9 to 12 hours can be expected overnight tonight and for 15 to 18 hours Tuesday evening into Wednesday morning. JSC will set record low temperatures today through Wednesday.

Rain, sleet and snow can be expected at JSC beginning tonight into Tuesday morning at JSC. Between 2.5 and 5 inches of snow is possible