Suomi NPP Visible Imagery from the Day Night Band, 0944 and 1125 UTC on 30 September 2015 (Click to enlarge)

The near-Full Moon provided ample illumination of fog/low stratus near the Oregon Coast early in the morning of 30 September, as shown above. Note also the clear skies near North Bend along the southern Oregon coast. What did the GOES-R IFR Probability field show at these two times?  IFR Probability fields also suggest clear skies around North Bend/Coos Bay (and offshore), as observed.  The fine fingers of fog/low stratus that are moving up river valleys in the 1125 UTC image most notably are not resolved by GOES-15 (which has a 4-km pixel size at the sub-satellite point). Both fields do capture the slow increase in cloud cover over land. Available surface observations show near-IFR conditions at some stations in Oregon.

GOES-R IFR Probabilities computed with GOES-15 and Rapid Refresh Data, 0945 and 1115 UTC on 30 September 2015 (Click to enlarge)