Everyone says "June and September are the best time in Montenegro". That's true — but it doesn't mean they're the same. There's 4°C of water-temperature difference between them, different wind patterns, different views on the mountains, and different prices. If you're choosing between these two months — this is for you. If you're still deciding about July-August — there's a note about that at the end too.
"In seven seasons I can't pick a favourite month. In June the bay smells different — those are wildflowers on the mountains. In September the light is different — the sun is lower. They're just two different summers." — Captain Alexey
Water temperature
June: 22°C at the start of the month, 24°C by the end. Swimming is comfortable all month, but in the first half it's bracing. September: 24°C at the start, 22°C by the end. The mirror of June. Warm water holds until around the 20th. In July-August water is 26-27°C — almost like a bath, ideal for kids.
Air temperature
June: 25-28°C in the day, 17-19°C at night. If your charter leaves at 9 in the morning, you'll want a light jacket — it's still cool on the water. September: 26-29°C in the day, 18-20°C at night. Slightly warmer than June. First half is still summer, second half is already autumn. In July-August it's 30-34°C in the day. On the deck under the sun without shade — unbearable. Everyone wants to be in the water.
Crowds
June: tourists are there, but Kotor isn't packed. On the Perast waterfront you can sit down at a restaurant without a booking. At the Blue Cave at noon — 3 to 5 boats at once, a 10-minute wait. September: similar to June, but by the 20th it's almost empty. Cruise ships come to Kotor with older tourists (not families), evenings are quieter. July-August: peak. The cave queue is 20-30 minutes, Kotor is crowded, restaurants need bookings. Anchorages full by 10am.
Prices
June: standard. 8-hour charter — €2,600. September: standard until the 15th, 10% off in the second half. May, October: 10-15% off. Coves are empty, prices are friendly, but the water is too cool / cooling for long swims. July-August: 10-15% premium on peak dates (15 July — 15 August). Slots fill a month ahead. If budget matters — October gives the best price-to-experience ratio. If your own comfort matters — first half of June and first half of September.
Wind
In the Bay of Kotor the wind is mild all year — the mountains protect. But some days it picks up. June: a calm month. Steady. The mistral kicks in maybe once every week or two, blows for half a day. September: storms are more frequent, especially in the second half. The easterly bura is cold and unpleasant. Passes in 2-3 days. If you need guaranteed daily outings — June. In September you can get a day when the wind doesn't let us do the full route (we switch to a short loop inside the bay).
Daylight and sunset
June: the sun sets at 20:30. Long evenings, golden hour 19:00-20:00. September: sunset is 18:30 (start) — 17:45 (end). Days are shorter, but the light in the sunset is more "gold" — because the sun is lower. For a 12-hour charter with a sunset — both months work. But in June the sunset is later, you can have dinner on deck after returning. In September it gets dark faster after sunset.
What's in season
June: wild herbs on the mountains, the smell of lavender and thyme. From anchor at Morinj you can smell them from the water. Pomegranate trees bloom in Perast. September: figs are ripe. At the Tivat market — wet, sweet, €3-4 per kilo. Grapes in the valleys. Smells of earth, not flowers. It's a small thing, but if you like specific scenes — June is "spring with flowers", September is "early autumn with harvest".
What to do on a bad day
Happens rarely, but it happens. In June: if there's a storm — we switch to a short route inside the bay (Perast, Our Lady of the Rocks). The storm lasts a day, the next is normal again. In September: bura can blow for 2-3 days. If your day catches it — we offer to move to the next available date, free. In July-August: weather is stable, but sometimes a thunderstorm rolls through in the evening. We skip the evening outing if the forecast is serious.
What's not usually written
In June the bay smells of mountain flowers. That's not marketing — it's a specific scent of lavender and thyme that drifts down to the water in the morning. By July it's gone. In September there's a moment in the second half — day is still summer, morning is already crisp autumn. You can swim in the day and have hot tea on deck in the morning. A rare combination. And: September is very different from first half to second. 1-15 September is summer. 16-30 is already autumn in the mountains and in the air, even though the water is still warm. If you want guaranteed summer — first half.
If picking a specific window
5-25 June — the most stable days of the season. Warm water, few tourists, flowers. 5-15 September — ideal if you want water slightly warmer than June and the same empty coves. 20-30 May or 20-30 October — great pricing, empty coves, but water is on the edge (18-20°C). Not recommended: mid-July to mid-August for anyone who wants quiet. Only if you're here for active beach time or with older kids who want warm sea.
