Hourly GOES-R IFR Probabilities starting at 0345 UTC 23 January overlain with the following hour’s Ceilings/Visibilities

Light winds and clear skies over Texas promoted the development of Radiation Fog early in the morning on 23 January 2013.  The animation above shows hourly snapshots of GOES-R IFR Probabilities and observations of Ceilings/Visibilities.  IFR conditions develop first near the coast and then spread inland.  IFR probabilities neatly match the regions of observed IFR conditions.  GOES-R products also include Cloud Thickness, below, which can be used to estimate the time of Fog Dispersal.

As above but for GOES-R Cloud Thickness

The GOES-R Cloud Thickness product estimates the depth of the single-layer water cloud in non-twilight conditions, and it shows the steady deepening of the fog/low stratus overnight, with the thickest clouds occurring in the triangle between San Antonio, Fredericksburg and Austin.  The depth of the clouds just before twilight conditions can be used to estimate cloud dissipation.  The time of that image is 1315 UTC (Note that twilight conditions have already occurred in Louisiana at this time), and is shown below:

GOES-R Cloud Thickness, 1315 UTC on 23 January 2013

 Maximum values of Cloud Thickness in central Texas are 1200-1300 feet, and according to this chart, that suggests a dissipation time of more than 4 hours, or sometime after 1715 UTC.  The visible image from 1745 UTC on 23 January, below, shows a small patch of stratiform clouds remaining where the thickest radiation fog had been.

GOES-13 Visible imagery, 1745 UTC on 23 January 2013

The animation below includes the traditional fog product, the brightness temperature difference between 10.7 µm and 3.9 µm.  The GOES-R product refines the satellite estimate of fog/low stratus by using data from the Rapid Refresh Model.

GOES-R IFR Probabilities (Upper Left), GOES-East Brightness Temperature Difference (10.7 µm – 3.9 µm) (Upper Right), GOES-R Cloud Thickness (Lower Left), GOES-East 10.7 µm imagery (Lower Right)