For most travelers, May to October is the easiest window for Portugal scuba. Mainland hubs like Sesimbra, Peniche and Berlengas, and Algarve (Lagos) get warmer water and more workable sea states, while winter brings larger Atlantic swell. If you need the most reliable year-round access, Madeira is usually the best bet. Expect mainland water roughly 14°C to 22°C depending on coast and month.

July to September is the best all-around window for Azores pelagic diving because it has the highest odds of calm seas for offshore banks. Plan bases like Pico and Faial, with add-ons like Santa Maria if you have time. Water is often around 20°C to 23°C in late summer, but wind and swell matter more than the thermometer. Build buffer days and treat offshore dives as weather-dependent attempts.

For the Algarve (Lagos), plan snorkeling for July to September when water is warmest and calmer days are more common. June and early October can still work if you get a cooperative forecast and choose sheltered coves. Even in summer, a 3mm to 5mm suit can make longer sessions more comfortable because Atlantic water can feel cool after time in the shade. If the ocean looks surgy at a rocky entry, switch bays or keep it a beach swim day.

A simple plan is 4-6 nights on the mainland plus 4-6 nights in Madeira. Use Lisbon (LIS) as your mainland gateway for Sesimbra and Lisbon Coast (Cascais), then fly to Madeira (FNC) for more consistent water time and hiking. If you want a beach reset, add 1-3 nights in Porto Santo. This combo works well when you have fixed dates because Madeira often saves the trip when mainland swell rises.

If the Azores are your priority, start with a mainland city break, then commit most of the trip to the islands. A common structure is 2-3 nights near Lisbon plus 7-10 nights in the Azores via Ponta Delgada (Sao Miguel). Add Pico and Faial for classic blue-water days. Schedule buffer days so weather cancellations do not wipe out your core dives. Keep your last 24 hours lighter before long flights if you are doing repetitive diving.

Portugal is not tropical, and the right suit depends on region and season. For the mainland, many divers use 5mm in peak summer and 7mm in shoulder months because water can range from about 14°C to 22°C. The Algarve is usually the warmest mainland option. In Madeira, a 3mm to 5mm can work in summer, while a 5mm is comfortable most of the year. In the Azores, plan 5mm to 7mm depending on your cold tolerance and the month, and bring a hood if you chill easily.

Berlengas is usually visited by boat from Peniche and Berlengas, and trips are highly seasonal and forecast-dependent. In peak periods, controlled access can apply, and you may need to register or pay an access tax through the BerlengasPass system. Book early for July and August weekends, and confirm whether your boat ticket includes the access requirement or if you must complete it separately. Treat Berlengas as a flexible "weather window" day rather than a fixed-date commitment.

Beginner-friendly diving in Portugal usually means sheltered bays, short boat rides, and flexible site choice. Sesimbra is a strong pick near Lisbon because it offers protected areas and lots of operator support. The Algarve (Lagos) is another solid option because it has the warmest mainland water and plenty of shallow sites when the sea is calm. For a calmer island environment and clear water, Madeira often works well for newer divers, especially outside peak winter swell.

The best strategy is to plan for flexibility and let local operators choose sites. On the mainland, swell and surge can spike quickly, especially on west-facing sites, so morning departures and sheltered coves are your friends. If your itinerary is fixed-date and dive-heavy, include Madeira because it often has more consistent access than exposed mainland coastlines. For shore dives, never commit to an entry if your exit is breaking, and avoid cave mouths when swell is running. A conservative call saves trips in Atlantic conditions.

Island hopping in the Azores uses a mix of short flights and seasonal ferries. A practical first-timer route is flying into Ponta Delgada (Sao Miguel), then adding Pico and Faial. Use ferries when schedules align, but expect routes and timing to change with season and weather. Book key legs early in July to September, build generous buffers, and avoid planning a long transfer on the same day you are counting on an offshore dive.

Treat cetacean encounters as a regulated activity. In the Azores and Madeira, reputable tours operate under licensing and approach rules designed to reduce stress on animals. For travelers, the practical takeaways are simple: book licensed operators, follow crew instructions, and do not pressure captains to chase or crowd wildlife. If you are diving in the Azores, remember that sea state drives safety. It is normal for operators to adjust plans or cancel. Schedule whale watching as a flexible day so it can move to the best conditions.

Yes, if you choose the right region for your goals. For sheltered technique sessions and easy logistics, Sesimbra and Algarve (Lagos) are practical mainland bases. For steadier conditions and clear water, Madeira is often the best option on fixed dates. The Azores (especially Pico and Faial) can be excellent for advanced blue-water training in summer, but only with a safety-first team and buffer days for weather. As a rule of thumb, plan June to October and expect water roughly 18°C to 24°C depending on region.