Hourly images of GOES-East IFR Probabilities and surface plots of visibilities/ceilings as well as 3-hourly HPC depictions of frontal positions, 0701 – 1515 UTC on 21 January 2014(click image to enlarge)

Frontal zones are often accompanies by lower visibilities, and the image above shows how IFR Probabilities march steadily eastward as a front marches eastward across the southern Gulf states. Thus, the IFR Probabilities can, at times, serve as a proxy for a frontal zone.