This is the METAR from 9:53 AM this morning.
KIAH 271553Z 12005KT 1/16SM FG VV002 18/18 A3009
Prevailing visibility is one-sixteenth of a statute mile, about 330', due to fog.
No defined ceiling is visible. Vertical Visibility (up into the fog) is 200'.
Temperate and dew point are both 18°C.
Altimeter setting in 30.09"hg.
Whether or not operations would be possible with that low visibility will depend on the Runway Visual Range (RVR) as measured at each particular runway. RVR is often higher than the prevailing visibility.