Santorini Weather, Month by Month

Reading Santorini’s calendar month by month

If you already have your dates fixed, the question is not “when should I go” — that tradeoff belongs to choosing the best time to visit — but “what will it actually be like.” Santorini’s weather moves in a fairly predictable arc: dry heat building through early summer, a windy peak in July and August, a slow cool down into autumn, and a quiet, half-closed winter. This page walks through that arc month by month, in the qualitative terms that actually help with packing and planning, rather than pretending to forecast an exact temperature for a date months away.

Two forces do most of the work: the sun, which is strong and reliable from May to September, and the meltemi, the seasonal north wind that builds through summer and eases by autumn. The mechanics of that wind — where it comes from, why it strengthens in summer — are covered on their own in the meltemi wind explained; here it only matters for what it does to your week: choppier crossings, cancelled boat trips, and cooler evenings on the caldera rim even in the hottest months.

A quick overview, season by season

Period	Air	Sea	Wind	What’s open
Nov – Mar	Cool, wettest months	Cold	Variable, calmer overall	Many caldera hotels, restaurants and cruises closed
Apr – May	Mild, warming	Still cool	Light to moderate	Reopening through spring
Jun	Warm, dry	Warming	Building	Fully open
Jul – Aug	Hot, driest	Warm	Strongest of the year (meltemi)	Fully open, busiest
Sep	Hot, easing	Warm	Easing	Fully open
Oct	Mild, cooling evenings	At its best	Light to moderate	Starting to wind down

This is the shape of the year at a glance. The sections below go month by month; for how this maps onto a specific trip length, see how many days in Santorini and the seasonal write-ups linked throughout.

Winter: November to March

This is Santorini’s quiet season, and it looks different from the postcard version of the island. Air is cool, rain is more likely than at any other point in the year, and the sea is cold enough that swimming is not really on the agenda. The bigger practical change is what’s closed: a large share of caldera-view hotels, restaurants and cruise operators shut for the season, some as early as late October and most not reopening until spring. Fira and a smaller set of year-round businesses keep the island functioning, but the choice that overwhelms visitors in July simply is not there in January.

Ferries also thin out in winter, both in frequency and in the number of routes running — worth checking against the Santorini ferry guide if a winter trip includes island hopping. None of this makes winter a bad time to be on the island; it makes it a different one, quieter and slower, and it should be planned as such rather than treated as a scaled-down summer. For a longer treatment of what a winter stay actually involves, see Santorini in winter and the winter itinerary.

Sunset, for what it’s worth, comes early in deep winter — around 5:15pm in late December — so plan dinner and any sunset walk accordingly rather than by a summer-season clock. For the wider question of where to watch it, see the Santorini sunset guide.

Spring shoulder: April and May

Spring is the island waking up. Hotels and restaurants that closed in autumn start reopening through April, ferry schedules thicken, and the light turns noticeably warmer. By May, days are pleasant and often sunny, and this is genuinely one of the more comfortable windows to be walking the Fira-to-Oia caldera path without the summer heat working against you.

The one thing spring does not deliver yet is a warm sea. After a winter of losing heat, the water is still cool through April and into May, so swims in early spring tend to be short rather than the all-afternoon kind. Sunbathing and walking are comfortable well before swimming is. If beach time matters more than caldera walks, this is worth factoring into a spring trip — see the Santorini beaches guide for what each beach is actually like once the season gets going, including the access caveats on the Red Beach.

Wind is generally lighter in spring than in summer, which also makes it a reasonable window for boat trips before the meltemi builds. A caldera day cruise booked in April or May tends to run more predictably than the same trip in peak summer.

Early summer: June

June is where Santorini shifts into full summer mode without yet reaching its hottest or windiest extreme. Days are warm and dry, the sea has had a full spring to warm further, and the island is open at full capacity — hotels, restaurants, wineries and boat operators are all running their regular schedules. It’s also a strong month for sunset watching: by late June, sunset falls late, around 8:50pm, which stretches the evening considerably compared with the depths of winter.

The meltemi is present in June but has not yet reached its summer peak, which makes it a comparatively steady month for boat-based plans, including diving. Visibility and conditions for a guided diving trip around the caldera are generally good before the wind picks up further in July.

Peak summer: July and August

This is Santorini at its most extreme in every direction: the hottest, driest weather of the year, the longest stretch of sun, and the strongest, most consistent meltemi. The wind is the detail most visitors underestimate — it can turn a calm morning into a choppy afternoon, and it is the single most common reason a caldera cruise, sunset sail or watersports session gets postponed or cancelled outright. Building a spare day into a July or August itinerary for exactly this reason is a reasonable precaution, not overcaution.

It’s also, unusually for a Mediterranean island, the start of harvest. Because Santorini’s vines are dry-farmed with no irrigation and the volcanic soil heats up fast, grapes ripen earlier here than almost anywhere else in Europe — picking often begins from late July into August, well ahead of harvests on the Greek mainland or further north. Visiting a winery in this window can mean seeing the crush in progress rather than just the vines; see the Santorini wine tasting guide and Assyrtiko explained for more on why the grape and the timing are connected, and the Santorini wineries area for where to base a visit.

Crowds peak in July and August too, which compounds with the heat: midday in Fira or Oia is the least comfortable time to be there in every sense. None of that is unique to this guide’s angle — it’s covered from the crowding side on best time to visit — but from a pure weather standpoint, expect heat, glare, and wind to be the three constants of a summer trip, and plan boat bookings with some flexibility.

Early autumn: September

September keeps most of summer’s heat while the wind starts to ease off its peak. It’s often the most comfortable stretch of the warm season: the sea is thoroughly warm after a full summer of heating, the island is still fully open, and the meltemi is less likely to disrupt a boat trip than in July or August. A sunset cruise booked in September tends to benefit from calmer water than the same trip a month or two earlier.

Harvest activity can still be visible into September in wineries that pick later, and the island’s rhythm — busy but not at its July peak — makes this a popular month with visitors who want summer conditions without the most extreme crowding.

Autumn shoulder: October

October is the mirror of May: air temperatures start cooling, particularly in the evenings, while the sea — having spent the whole summer warming up — is at its best for swimming. It is one of the more underrated months for beach time for exactly this reason. Wind is generally lighter than in summer, and the number of tourists on the caldera path and in Oia thins out compared with peak season.

By later in the month, some businesses begin winding down toward the winter closures described above, so it’s worth checking specific hotels, restaurants or boat operators rather than assuming everything is still running at full summer capacity. For a broader comparison of what April–May and September–October each offer, see Santorini in the shoulder season.

Wind, sea and the ground: what doesn’t change with the seasons

A few things about Santorini are worth separating from the monthly weather pattern, because they are constant rather than seasonal. The island has no rivers or natural freshwater supply at any time of year; tap water comes from desalination and is drinkable but not something residents choose to drink. The volcanic ground itself does not change with the seasons either — beach sand stays black or reddish and hot underfoot whenever the sun is out, whatever the month.

Volcanic activity is also worth separating clearly from weather. The seismic swarm that began in January 2025 between Santorini and Amorgos lasted around forty days, produced tens of thousands of small earthquakes, and prompted a temporary local state of emergency — but it did not lead to an eruption, and it has been over for some time. It has no bearing on the seasonal patterns described on this page, and it isn’t a reason to expect different weather in any given month; for the fuller picture, see Santorini safety and the 2025 earthquakes.

Whatever month you’re travelling in, a look at the Santorini packing list is worth pairing with this page — what you pack for a windy August week and a mild October one is not the same, even though both fall inside the island’s long open season.

And if the trip includes more of the Cyclades than just Santorini, seasonal closures and ferry frequency both affect island hopping routes, so it’s worth checking those against the month of travel too. For a wider spread of activities that flex well across seasons, see Awesome Santorini Spots or book directly through a guided highlights tour that adapts to whichever month you land in.

Santorini weather questions, month by month

What is the weather like in Santorini in July and August?

Hot and dry, with little rain and the meltemi wind blowing hardest of the year. Expect strong sun, breezy evenings on the caldera rim, and occasional cancelled boat trips when the wind picks up mid-afternoon.

Is the sea warm enough to swim in May?

The sea is still cool in May, having spent the winter losing heat, so swims tend to be brief. Air temperatures are already pleasant, which is why many visitors sunbathe more than they swim early in the month.

Is October a good month to swim in Santorini?

Yes. By October the sea has spent all summer warming up and is at its best, even as the air starts to cool in the evenings. It is one of the more comfortable months for beach time on the island.

What closes in Santorini over winter?

Many hotels, restaurants and caldera cruise operators close for the season from November through March. Fira and a handful of businesses stay open year-round, but choice narrows sharply compared with summer.

When does the grape harvest happen in Santorini?

Harvest starts early compared with most of Europe, often from late July into August, because the island’s heat and lack of irrigation push the Assyrtiko vines to ripen ahead of schedule.

Does the meltemi wind affect boat trips?

Yes, especially in July and August, when the meltemi blows hardest and can delay or cancel caldera cruises, sunset sails and watersports for a day or more at a time.

What time does the sun set in Santorini in summer versus winter?

Sunset shifts a lot across the year: around 8:50pm in late June versus around 5:15pm in late December. There is no fixed hour, which is why sunset plans should always be checked for the actual date of the trip.

Is Santorini’s weather or safety affected by the 2025 earthquake swarm?

No. The seismic swarm that began in January 2025 was intense but ended after about forty days with no eruption, and it has no bearing on the island’s ordinary seasonal weather patterns described here.