Webcams are the most practical way to see the beach, by desire or curiosity, on days of great swell or on calmer days, and go when big if you can.
Here you can see the detailed surf forecast report of Praia do Norte in Nazaré, Portugal, powered by windguru.
Note: Forecasts can change/fail, check it regularly here, it will be updated, it is more accurate the closer to the date.
Usually when the wave height is above 3 meters (~10 foot) in the forecast (actually the Nazaré canyon can amplify this value 3x), the period of the waves is above 14 seconds and the wind is not very strong and offshore, we have good conditions for big waves! Check the windguru Nazare forecast in the table bellow:
To see real-time monitoring of values measured by buoys in the sea off Nazaré, visit the website Monican from the "Instituto Hidrográfico" of Portugal. You can view wave height and period, the wind, and another data, measured in different areas of the canyon in real time.
Check also the Nazare North Canyon - big waves generator.
Check also the Tourism Nazare.