Climate in Koper, Slovenia

Koper, Slovenia has a humid continental climate. The annual average temperature is about 11.1°C, with around 1167 hours of sunshine; the national rainfall baseline is roughly 1299 mm across 143 rainy days a year. The warmest month is Jul (highs near 26.1°C) and the coldest is Jan (lows near -3.9°C). These are deterministic planning estimates, not a forecast or measured station data. Temperature and sunshine follow the city's latitude; rainfall and the climate zone come from a country-level baseline that every city in the country shares (refined by region in the United States, Canada and Australia), so they do not show local differences. Check current conditions with an official meteorological service before travel.

Data year 2025; last updated 2026-05-16.

Koper is classified as Humid Continental. The classification combines the city’s own temperature range, which follows its latitude, with a rainfall pattern taken at country level for Slovenia — so cities in the same country usually share a zone.

The rainfall baseline for Slovenia is about 1299 mm a year over roughly 143 rainy days, with the wettest month Jun and the driest Jan. This figure is not specific to Koper: every city in Slovenia carries the same baseline, so it will not show the difference between, say, a dry inland city and a wet coastal one. Use an official meteorological service for local rainfall.

Koper sees an estimated 1167 hours of sunshine a year, concentrated in the warmer months around Jul.

By temperature and rainfall, the most comfortable months in Koper are Sep, May, Aug. Conditions vary year to year — verify with a current forecast before booking.

Koper has a climate comfort score of 64/100, a comfortable year-round climate by this measure. The score weights mild temperatures most, then rainfall balance, sunshine, low seasonality, and the absence of extreme winter cold or summer heat.

• Climate in Ljubljana — Humid Continental, comfort 64/100
• Climate in Maribor — Humid Continental, comfort 63/100
• Climate in Celje — Humid Continental, comfort 63/100