These "FICON" NOTAM's contractions aren't in the FAA contraction list. What do they mean?
FICON is outlined in FAA JO 7930.107 "FICON REPORTING". 

FICON is the "FIeld CONditions reporting. It identifies information that used to be called "braking action", but is now a little more succinct. 

The conditions for the runway are reported in thirds, [First Third]/[Middle Third]/[Last Third], with the following data outlined on page 6:



So 5/5/5 means that the runway is covered with frost or is wet and is "damp or 1/8" or less of standing water". Pilots used to report this as "good" braking action.