Signature of the coastal circulation variability in altimetric data in the southern Bay of Biscay during winter and fall 2004

►We study the signature of coastal currents in the Bay of Biscay in 2004. ►Altimetry depicts the main occurrences of the Iberian Poleward Current in winter. ►Geostrophic currents are in good agreement with in situ data and a simulation. ►Local inconsistencies can be found in high-frequency altimetric signals. ►Altimetry should be used in the monitoring system of Navidad events.