Hvar’s mean nightly minimum falls from 20.8 °C in August to 17.7 °C in September and 14.3 °C in October, while the sea only drops from 23.5 °C to 20.6 °C. The outdoor night ends several weeks before the swimming does.
The one measurement that matters after dark
Every page about this island quotes daytime temperatures, and daytime temperatures are the wrong series for the question. What decides whether an evening outdoors is pleasant or a mistake is the overnight minimum, and the Croatian meteorological service publishes one for Hvar town — one of only a handful of island stations in the normals.
It is a steeper curve than the daytime one. The island keeps its reputation for a long season because the sea and the sunshine hold up, and both of those are day figures. The night falls away faster, and it falls away first.
Mean daily minimum temperature at the Hvar town station, January to December, °C. Source: DHMZ (meteo.hr), climate normals 1971–2000.
August sits at 20.8 °C and September at 17.7, a fall of 3.1 °C in four weeks. October is 14.3. That is a 6.5 °C drop across two months, against a sea that gives up only 2.9 °C over the same stretch.
| Month | Mean daily minimum, Hvar | Mean daily maximum, Hvar | Sea, Hvar | Mean daily minimum, Split | Mean daily minimum, Dubrovnik |
|---|---|---|---|---|---|
| June | 18.3 °C | 26.4 °C | 20.8 °C | 18.9 °C | 18.9 °C |
| July | 20.9 °C | 29.5 °C | 22.9 °C | 21.7 °C | 21.4 °C |
| August | 20.8 °C | 29.5 °C | 23.5 °C | 21.7 °C | 21.6 °C |
| September | 17.7 °C | 26.0 °C | 22.4 °C | 18.0 °C | 18.4 °C |
| October | 14.3 °C | 21.8 °C | 20.6 °C | 14.1 °C | 14.9 °C |
Hvar is the coolest of the three at night in every month of that table. In July it runs 0.8 °C below Split and 0.5 °C below Dubrovnik. An island in open sea with a big daily range does that: it gives back more of the day’s heat than a mainland harbour does. The daytime figures are why people come; the nighttime figures are why September evenings here surprise them.
mean nightly minimum
The warm night, and the full timetable behind it
Days reach a mean maximum of 29.5 °C, the sea holds 23.5 °C and 29.9 days of the month reach 25 °C. This is also the only stretch when all 17 commercial routes in the national register are running, which is what puts the extra boats on the Split corridor.
The boat home, and why no time appears on this page
The obvious question is what time the last service leaves, and this page will not answer it. The per-line timetable for line 604 — the one vehicle service that docks at Hvar town — is not in the source bundle this site works from, so its departure times, crossing duration and fares are all unverified. Printing one recalled from somewhere else would be the single most dangerous thing this page could do, because unlike a wrong temperature a wrong last sailing strands you.
What the register does support is the shape of the risk. Sixteen services connect Split with the island and 13 reach Hvar town, but nine of those 13 are commercial lines carrying no public service obligation. They exist because summer demand supports them. Four state services remain in winter.
Planning the evening around a boat with no obligation to sail
A late return to Split in August is running on capacity that is contractually optional. Nine of the thirteen services reaching Hvar town are commercial, and a commercial operator withdraws a sailing when the season ends or the weather turns, without owing anybody a replacement. The state core — four services in winter — is what you can actually rely on.
The practical consequence is that a night out on this island is a night spent on this island. Book the bed here rather than the boat back, and check the operator’s own published times on the day. Which of the three towns to sleep in is a different question from which one to arrive at, and the corridor page lists all sixteen services with their operators.
Put the two halves together and the calendar answers itself. The warm night runs out at the end of August; the reliable boats run out at the end of the season; and the sea, which is the thing most people are actually optimising for, outlasts both. If the evenings are the point of the trip, come in August and sleep on the island. If the water is the point, September and October are better and quieter.
What do you need to work out next?
The month is settled. These follow from it.
Where to stay
Which town should the bed be in?
Thirteen of sixteen services reach Hvar town; two carry a car and one of those docks there.
Getting around
Which services actually run in winter?
Four state services remain; the other nine to Hvar town are commercial.
When to go
Is September still warm enough at night?
The nightly minimum falls from 20.8 °C to 17.7 °C between August and September.
Planning
How big is the island really?
Four ferry harbours, and Sv. Nikola is the third highest island point in the country.
Climate data: DHMZ (meteo.hr), climate normals 1971–2000. Ferry data: Agencija za obalni linijski pomorski promet (ZOLPP), 2026 state coastal line register and per-line timetables.