Weather in Sisak - 14-day forecast

Detailed weather forecast for Sisak, Croatia: daytime and night temperature, rain, sunrise and sunset - today and for the next two weeks.

Forecast for the next days in Sisak

today☀️ 31°💧 1.1 mm

Sun🌤️ 27°💧 1 mm

Mon☀️ 28°💧 3.7 mm

Tue☀️ 29°💧 0.2 mm

Wed🌧️ 30°💧 2.5 mm

Thu🌧️ 21°💧 2.3 mm

Fri☁️ 22°💧 0.3 mm

Sat☁️ 25°💧 13.3 mm

Forecast vs 1991-2020 climate normal

How does the current forecast compare with normal?

We compare the coming days with weather usually observed at this time of year.

NASA POWER

Saturday 5 Sept in Sisak, the forecast high is 31°C. Typical daytime temperatures at this time of year range from 21°C to 29°C, so it will be warmer than usual. It is warmer than 88% of similar days.

Saturday 5 Sept

31°Cwarmer than usual

usually 21°C–29°C

warmer than 88% of similar days

night: exceptionally warm rain: typical rainfall wind: exceptionally strong

Sunday 6 Sept

27°Cnear normal

usually 21°C–29°C

night: exceptionally warm rain: typical rainfall wind: exceptionally strong

Monday 7 Sept

28°Cwarmer than usual

usually 21°C–29°C

warmer than 72% of similar days

night: exceptionally warm rain: more rain than usual wind: typical

Tuesday 8 Sept

29°Cwarmer than usual

usually 21°C–29°C

warmer than 83% of similar days

night: exceptionally warm rain: typical rainfall wind: typical

Wednesday 9 Sept

30°Cwarmer than usual

usually 21°C–29°C

warmer than 88% of similar days

night: exceptionally warm rain: more rain than usual wind: typical

Thursday 10 Sept

21°Ccooler than usual

usually 21°C–29°C

cooler than 79% of similar days

night: warmer than usual rain: typical rainfall wind: exceptionally strong

Friday 11 Sept

22°Cnear normal

usually 20°C–28°C

night: exceptionally warm rain: typical rainfall wind: exceptionally light

How warm was this week in previous years?

Each bar shows the average daily high during the same 7-day period in each year.

swipe to see more years →

cooler yearstypical rangewarmer years2026 forecastcurrent forecast

From 1981 to 2025, the 5-11 Sept period averaged 25°C by day. The coolest year was 2007 (18°C) and the warmest was 2008 (31°C). The current forecast averages 27°C - higher than in 71% of historical years.

Historical reference: NASA POWER daily gridded data (MERRA-2), the 1991-2020 normal and a +/- 7-day calendar window. The typical range is the 20th-80th percentile. This is not a city weather-station reading and does not change the current forecast. NASA POWER Daily API.

Weather warnings - Sisak

No active weather warnings for Sisak (region: Karlovac region). The national weather service is not forecasting dangerous conditions.

14-day forecast - Sisak

Sisak - 14-day weather forecast infographic

Sisak 30 & 45-day weather - long-range outlook

Next 16 days · forecast

26°

around 19° at night · days with rain: 8

Weeks 3-4 · avg for September

22°

around 11° at night · rain chance 50%

Weeks 5-7 · avg for October

17°

around 7° at night · rain chance 42%

The 30 & 45-day outlook for Sisak: the next 16 days are a numerical forecast updated daily - on average 26° by day and 19° at night. Further out we rely on multi-year climate averages: around 22° in September, and about 17° in October. Forecasts beyond two weeks are indicative only.

Day-by-day forecast for Sisak

Saturday5 September 2026

☀️31°clear sky

sunrise 06:20 · sunset 19:26 · night 19° · evening 26° · rain 1.11 mm · humidity 27% · wind 7 m/s · clouds 2%

Sunday6 September 2026

🌤️27°scattered clouds

sunrise 06:21 · sunset 19:24 · night 18° · evening 29° · rain 0.96 mm · humidity 34% · wind 4 m/s · clouds 38%

Monday7 September 2026

☀️28°clear sky

sunrise 06:23 · sunset 19:22 · night 20° · evening 30° · rain 3.72 mm · humidity 25% · wind 3 m/s · clouds 2%

Tuesday8 September 2026

☀️29°clear sky

sunrise 06:24 · sunset 19:20 · night 22° · evening 34° · rain 0.18 mm · humidity 26% · wind 3 m/s · clouds 7%

Wednesday9 September 2026

🌧️30°light rain

sunrise 06:25 · sunset 19:18 · night 18° · evening 30° · rain 2.51 mm · humidity 26% · wind 3 m/s · clouds 5%

Thursday10 September 2026

🌧️21°light rain

sunrise 06:26 · sunset 19:16 · night 16° · evening 24° · rain 2.25 mm · humidity 52% · wind 5 m/s · clouds 79%

Friday11 September 2026

☁️22°overcast clouds

sunrise 06:27 · sunset 19:14 · night 17° · evening 26° · rain 0.33 mm · humidity 46% · wind 2 m/s · clouds 100%

Saturday12 September 2026

☁️25°broken clouds

sunrise 06:29 · sunset 19:12 · night 21° · evening 29° · rain 13.26 mm · humidity 44% · wind 1 m/s · clouds 83%

Sunday13 September 2026

🌧️20°light rain

sunrise 06:30 · sunset 19:10 · night 14° · evening 15° · rain 1.11 mm · humidity 64% · wind 6 m/s · clouds 98%

Monday14 September 2026

☀️21°clear sky

sunrise 06:31 · sunset 19:08 · night 15° · evening 25° · rain 3.78 mm · humidity 53% · wind 2 m/s · clouds 1%

Tuesday15 September 2026

☀️23°clear sky

sunrise 06:32 · sunset 19:07 · night 20° · evening 29° · rain 0.18 mm · humidity 40% · wind 1 m/s · clouds 100%

Wednesday16 September 2026

🌧️29°light rain

sunrise 06:33 · sunset 19:05 · night 19° · evening 30° · rain 0.66 mm · humidity 40% · wind 4 m/s · clouds 1%

Thursday17 September 2026

🌤️25°a few clouds

sunrise 06:35 · sunset 19:03 · night 20° · evening 29° · rain 50.67 mm · humidity 48% · wind 3 m/s · clouds 23%

Friday18 September 2026

☀️27°clear sky

sunrise 06:36 · sunset 19:01 · night 21° · evening 31° · humidity 39% · wind 2 m/s · clouds 7%

Saturday19 September 2026

☀️28°clear sky

sunrise 06:37 · sunset 18:59 · night 21° · evening 33° · humidity 37% · wind 2 m/s · clouds 56%

Sunday20 September 2026

☀️29°clear sky

sunrise 06:38 · sunset 18:57 · night 25° · evening 34° · humidity 32% · wind 2 m/s · clouds 1%

UV index in Sisak - is it safe to sunbathe?

Today the UV index in Sisak is 6 (moderate) - unprotected fair skin can burn in about 35 minutes. Seek shade around midday. SPF 30+, sunglasses and a hat for longer stays.

Pollen in Sisak - info for allergy sufferers

Today ragweed pollen is highest in Sisak - about 622 grains/m³, very high level. Allergy sufferers should limit time outdoors on dry, windy days and take medication as advised. Pollen levels are a CAMS model forecast and are indicative.

Sisak weather through the year

Warmest, driest months on average: April, May, June, July.

Upcoming public holidays in Croatia: All Saints' Day — 1 November · Remembrance Day — 18 November · Christmas Day — 25 December.

Nearby and related places

Velika GoricaZagrebPrijedorSamoborSplitKorčulaKarlovac

FAQ - Sisak weather

What is the weather like in Sisak today?

Today it is about 31° during the day and 19° at night, clear sky.

How far ahead can I check the forecast for Sisak?

This page shows a detailed 14-day forecast plus the long-term monthly climate, so you can plan both a short trip and a holiday months ahead.