Maximum tides in coastal areas need to be a concern because they often cause tidal flooding. Analysis of maximum tides on the west coast of Sumatra uses long-term data from Sabang 13 years (2005–2018), Sibolga 28 years (1989–2004, 2005–2018), and Padang 25 years (1986–1998, 2005–2018). The analysis of maximum tides is associated with the analysis of the lunar and solar astronomical parameters that influence them. In general, the daily tide pattern has a semi-diurnal pattern which is related to the influence of the lunar phases which is clearly indicated by the monthly variation pattern. Maximum tides reach their peak during the new and full moon which is strengthened by lunar perigee conditions. Spectral analysis shows a semi-annual dominant period which is influenced by variations in solar declination. This is also shown by the annual variation of maximum tides which peak around June when the sun is most north (maximum declination 23.5°) and around December when the sun is furthest south (minimum declination −23.5°). There is no indication of the 18.6 years variation due to the lunar nodal cycle. Maximum tides are dominantly influenced by the moon phase, the nearest distance between the moon and the earth (perigee), and the sun’s declination, which can be an early warning of potential flooding. The tidal flood on Padang coast on June 6 2024 is related to the new moon (June 6), perigee (June 2), and the northernmost sun (June).