That's as big as it get's, thanks to a big underwater canyon ending right in front of the Praia do Norte. The swell comes to the shore and with the end of the canyon the wave will be build up to what we know the Nazaré wave.
This waves are from the crazy Wednesday in November 2018. Over night the waves were building up. Right before midnight I drove down to the faro, the lighthouse from Nazaré, it was dark no light no stars and no moon. No horror movie will ever be as impressive as the noise of these waves crashing in the rocks below the lighthouse.
The next morning with the first light I finally could see with my eyes the Nazaré waves.
Question: Do you see the Fibonacci curve?