Daily Archives: December 27, 2012

Predicting the dissipation time of Radiation Fog

GOES-R IFR Probabilities (Upper Left), GOES Brightness Temperature Difference (10.7 µm – 3.9 µm) (Upper Right), GOES-R Cloud Thickness (Lower Left), GOES Visible (0.62 µm) (Lower Right) at 1400 UTC on 27 December 2012.

GOES-R Cloud thickness can be used to predict how long it will take radiation fog and low stratus to burn off after developing overnight.  This case from the high plains of Colorado, on December 27th, is typical.  At 1402 UTC, La Junta Colorado is in a region of enhanced IFR Probability, with 2-mile visibilty and 400-foot ceilings.  The Cloud Thickness at this time, the last image available before twilight conditions, was as much as 1200 feet.  This scatterplot suggests that the fog will be gone in 4-5 hours.  The 1732 UTC image, below, shows the final remnant of low cloud persisting (it was not present at 1815 UTC).  Although difficult to see in the visible imagery, perhaps because of snow-covered ground, it shows up well in both the IFR probability field, the Brightness Temperature Difference field, and the Cloud Thickness field.

As above, but at 1732 UTC.