I didn't tag @ASGIRC in with my further comment, but FWIW the official situation a while back, in 2017 from the Portuguese AIP (official source of info) for FNC was,.... and here comes the techie stuff:
Wind Limitations, When landing:
- Maximum of two minutes mean Wind Speed Values indicated by the Touchdown anemometer: • In the sector 300° to 010° MAG (clockwise) - 15KT, with the maximum Wind Gust of 25KT.
In the sector 020° to 040° MAG (clockwise) - 20KT, with the maximum Wind Gust of 30KT.
In the sector 120° to 190° MAG (clockwise), and if Runway in use is 05 - 20KT with a maximum Wind Gust of 30KT, and if Runway in use is 23 - 15KT, subject also to maximum Wind Gust of 25KT as indicated by MID Anemometer.
2.Maximum of two minutes mean Wind Speed Values, including Gust indicated by the MID or ROSÁRIO Anemometers • In the Sector 200º to 230º MAG (clockwise) - 25KT.
So to cut to the chase when that lot was written while back in 2017 there was no blanket 15 knot limit but it is quite possible rules have changed so I'm ready to be corrected.