Kefalonia weather by month

The best time to visit Kefalonia is June to August — 93/100 in July, 32°C and 1 rainy day. The best season is summer, June to August (92/100 on average).

The worst month is January at 54/100 — cool, rainy, clean air. See January →

Updated September 2026 · climate normals from ERA5 reanalysis

Planning the wider trip? Best time to visit Greece →

Kefalonia🇬🇷 Greece · Greece & Cyprus · Island93
  1. 54Jan
  2. 65Feb
  3. 72Mar
  4. 78Apr
  5. 83May
  6. 92Jun
  7. 93Jul
  8. 91Aug
  9. 87Sep
  10. 79Oct
  11. 61Nov
  12. 56Dec

Best season: June to August (92/100 on average) · worst January (54/100)

Days
32°C
Nights
23°C
Wet days
1
Sun
13.3 h
Humidity
80%
Daylight
15 h
Kefalonia, Greece
Photo: Valentina Nicola · Pexels

Kefalonia, month by month

Comfort score out of 100 for the kind of trip Kefalonia is best for, the average high, rainy days and hours of sun a day from the climate normals, and how busy it tends to be.

MonthScoreTierHighRainSunCrowdsOn
Jan54D15°C14 d8 hBusy1
Feb65C16°C9 d9 hBusy2
Mar72B18°C11 d10 hBusy3
Apr78B21°C5 d11 hPeak2
May83A24°C4 d12 hShoulder2
Jun92S29°C2 d13 hBusy3
Jul93S32°C1 d13 hBusy3
Aug91S32°C2 d13 hPeak6
Sep87A29°C5 d11 hBusy4
Oct79B25°C8 d9 hBusy3
Nov61C21°C14 d8 hQuiet1
Dec56D17°C13 d7 hBusy1

What's on in Kefalonia through the year

Festivals, natural spectacles, holidays and the seasons to watch out for — curated and sourced. The month pages carry the detail.

February
  • Clean Monday23 FebHoliday
March
  • Independence Day25 MarHoliday
April
  • Orthodox Easter10–13 AprHoliday
May
  • Loggerhead turtles1 May – 15 Sep (usually)Nature
June
  • Wildfire season15 Jun – 30 SepHazard
  • Sea warm enough to swim1 Jun – 15 Oct (usually)Season
August
  • Snakes of the Virgin, Markopoulo6–16 AugFestival
  • Robola harvest20 Aug – 30 Sep (usually)Nature
  • August peak1–31 AugHoliday
October
  • Ohi Day28 OctHoliday
  • Out of season20 Oct – 15 AprSeason

Everything on in Kefalonia through the year →

Crowds in Kefalonia in July

How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.

BusySummer holidays in Greece, school holidays in 7 of the markets that fill it(estimated)

JFMAMJJASOND

Peak crowdsBusyShoulder seasonQuiet

Traveller notes on Kefalonia

What people who have been say about the place — the year-round notes first, then month by month.

Forum posters describe February as genuinely capable of turning cold and wet, with occasional snow reported at higher elevations and past floods on the island in this general window. Posters are consistent, though, that Kefalonia's weather is notoriously hard to predict and varies dramatically even bay to bay - it's common for one part of the island to be sunny while another sees rain at the very same time, and a passing storm here typically clears relatively quickly back to milder, sunnier conditions rather than settling in for days. Overall, posters frame February as a real winter month with cold, wet stretches, but not a write-off - flexibility about which part of the island to be in on a given day helps make the most of it.
Tripadvisor community · February · 1 month ago · Read more on Tripadvisor ↗
Regulars describe the sea here with a level of detail worth keeping: by late May the top metre or so has warmed while it stays noticeably colder just beneath, swimmable rather than comfortable for lingering. Our column reads 18.7C, and regulars specifically recommend June instead if the sea and settled weather matter more than avoiding crowds, since June's water is warmer even if only marginally so early in the month. Our row for May gives 23.9C reading as 25C over 15.9C nights, with 24.1mm of rain across 4.4 days - changeable early in the month, improving as it goes. The island stays genuinely quiet through May, busier but not excessively so once June arrives. The record: humidity 80 percent, 12.2 hours of sun, a 24.8 kph wind and AQI 55.
WarmOnTopChillyABitDeeper · May · 1 month ago · Read more on Tripadvisor ↗
June on Kefalonia is good and, by regulars' own accounts, unpredictable: some describe 28C days with 17 or 18C evenings, others 30 to 36C and nights that never turn chilly. Our row's 29.3C over 20.3C sits between the two, reading as 33C, with 15.1mm across 1.7 precipitation days and 13.3 hours of sun. Early June still has low visitor numbers, with the main towns busier but not oppressive, and everything is in flower and green before the summer burns it off. The island's famous beach comes with a condition: Myrtos is very exposed to wind and weather, so the postcard version needs a still day - our 22.4 kph is the average it has to beat. The record: humidity 81 percent, a 23.1C sea and AQI 57.
MyrtosNeedsAStillDay · June · 1 month ago · Read more on Tripadvisor ↗
July on Kefalonia runs into the mid-30s C and often does not drop below 20C overnight, and the forum's specialist subject is the wind. It comes mostly from the west or northwest, strengthens through the late afternoon, and on a northerly day it makes swimming at the west-coast beaches - Myrtos above all, and Petani - genuinely dangerous rather than merely choppy. The wind itself is not cold; the problem is the water. The standing advice is to keep the famous beaches for calm days and have a sheltered east-coast alternative in mind. The record: 31.7C days that feel like 37C, 22.7C nights, 0.9 precipitation days, 13.3 hours of sun, a 25.7C sea and a 25 kph wind.
MyrtosOnTheWrongDay · July · 1 month ago · Read more on Tripadvisor ↗
Kefalonia's forum puts August around 30°C in the shade with roughly 12 hours of sunshine a day, capable of hitting 40°C on the hottest days especially early in the month. Regulars describe the classic siesta rhythm — sightseeing before 11:30am, shade and a long lunch through the peak heat, back out around 4pm — and note the Greek heat feels notably less oppressive than a 30°C day in a humid climate.
Tripadvisor community · August · 1 month ago · Read more on Tripadvisor ↗
Regulars describe September as hot by day, sometimes cool and changeable in the first week and then settled, with any rain arriving warm. Our row gives 28.6C reading as 32C over 20.6C nights, and 64.3mm across only 4.9 days, so the wet part is brief. The sea, they say, is at its warmest now - 25.2C on our reading, level with the air's daily mean. The crowds of July and August have gone while everything stays open, with one caveat worth knowing: as the season winds down the resorts quieten and menus can narrow, because stocks are run down rather than replaced. The main villages are still working in late September. The record: humidity 72 percent, 10.8 hours of sun and a 25.2 kph wind.
TheMenusGetShorter · September · 1 month ago · Read more on Tripadvisor ↗
Regulars are honest this month comes down to luck - some visitors get genuinely good weather throughout, others hit a rainy, changeable stretch, the rain itself typically warm rather than a cold soak. Our row backs that mild, genuinely wet read, 24.8C reading as a hot 25C, over 17.3C nights feeling 16C, with a substantial 107.1mm of rain across 8.3 days and a real 26.9 kph wind. Regulars are consistent by mid-to-late month most smaller resorts have shut down for the season, Argostoli and Lixouri the recommended base since they stay open and genuinely lively regardless. The sea sits at a warm, swimmable 24.6C, right at the lower edge of comfortable for most swimmers. The record: 9.4 hours of sun and AQI 50.
ComesDownToLuckArgostoliStaysOpen · October · 1 month ago · Read more on Tripadvisor ↗

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