Early September 1 September
78°F
Typical afternoon high
32% historical wet-day frequency
Slovenia · Mountains
Is September a good time?
September averages 73°F afternoons and 73°F seas, with about 10 rain days. Later September is typically cooler.
Historical Zahodna Slovenija regional averages, not a forecast or a measure of queues. Overnight demand compares average stays per day. Covers Ljubljana, Lake Bled, Piran and Julian Alps; conditions vary within the region.
This weather score measures sightseeing comfort. Snow and ski conditions need a separate check.
What matters most?
Weather 50% · Crowds 30% · Cost 20%
#4 of 12 months here · Balanced mix
Overall combines weather, overnight demand and cost. It does not include sea temperature.
Plan your September
Afternoons around 73°F (23°C): T-shirt weather; nights around 54°F (12°C): a sweater and a light jacket. Bring rain gear: about 10 days with at least 1 mm of rain. About 13 hours of daylight.
The sea averages 73°F. Our swimming guide: comfortable for a swim. Your comfort will vary. This is open water near the coast, not a beach-specific reading.
Monthly coastal averages from NOAA, 2011–2025. Sea temperature is separate from the weather and Overall scores.
The sun rises about 06:40 and sets about 19:18 (local time, mid-month). Mornings start around 54°F (12°C); afternoons reach about 73°F (23°C). Expect rain on about 10 days in a typical September.
Early, middle or late?
Early September is typically warmer. The afternoon high averages 78°F on the 1st, versus 67°F on the 30th. Historical wet-day frequency rises from 32% to 35% between those dates.
78°F
Typical afternoon high
32% historical wet-day frequency
73°F
Typical afternoon high
32% historical wet-day frequency
67°F
Typical afternoon high
35% historical wet-day frequency
Historical daily averages from 2011–2025, smoothed over two weeks. A seasonal pattern, not a forecast. This does not establish which week has the lowest prices or fewest visitors.
Weather shows historical patterns, not a forecast. Holidays and events use the dates shown for 2027.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
| 178° | 278° | 378° | 477° | 577° | ||
| 676° | 776° | 876° | 975° | 1075° | 1175° | 1274° |
| 1374° | 1474° | 1573° | 1673° | 1772° | 1872° | 1971° |
| 2071° | 2171° | 2270° | 2370° | 2469° | 2569° | 2669° |
| 2768° | 2868° | 2967° | 3067° |
Afternoon high rain likely (25%+) local school holidays public holiday event
School-holiday dates for September 2027 aren't available in our data yet. A day without a school marker doesn't mean schools are open.
Afternoons cool from about 77°F (25°C) in the first week to 68°F (20°C) in the last. The chance of a wet day runs 31–37%.
Visitor season
Moderate season. September averages 53% of August's overnight stays per day. Fewer overnight stays than August.
Overnight stays across Zahodna Slovenija do not measure queues, day visitors or congestion at individual sights. For its size, busier than most of Europe this month.
Hotel price season
A little above usual. Estimated from national hotel prices and local visitor demand; no measured regional room rate is available.
Fewer overnight stays do not automatically mean cheaper rooms. Check actual quotes for your trip.
Year-to-year variation
In the 15 years from 2011 to 2025, the month's afternoons averaged between 67°F (19°C) and 78°F (26°C); in 12 of them they were within 3°F (1.5°C) of the typical 73°F (23°C). Rain days ranged from 5 to 16; half the years had 7–13.
Rain days in each September
| Year | Afternoon high | Rain days |
|---|---|---|
| 2011 | 78°F | 5 |
| 2012 | 72°F | 12 |
| 2013 | 71°F | 10 |
| 2014 | 70°F | 13 |
| 2015 | 70°F | 11 |
| 2016 | 75°F | 7 |
| 2017 | 67°F | 16 |
| 2018 | 74°F | 9 |
| 2019 | 73°F | 9 |
| 2020 | 74°F | 9 |
| 2021 | 74°F | 6 |
| 2022 | 71°F | 13 |
| 2023 | 76°F | 6 |
| 2024 | 72°F | 14 |
| 2025 | 73°F | 11 |
Checked against official climate averages for Ljubljana Bezigrad. How we check
Compare dates
| Typical conditions | Aug | Sep | Oct |
|---|---|---|---|
| Afternoons | 83°F | 73°F | 63°F |
| Sea | 78°F | 73°F | 67°F |
| Rain days | 9 | 10 | 9 |
| Overnight demand | 100% | 53% | 31% |
August: Warmer afternoons and warmer sea than September. More overnight demand. August guide →
October: Cooler afternoons and cooler sea than September. Less overnight demand. October guide →
Overnight demand measures accommodation stays, not queues. Sea temperatures are monthly coastal averages.
Yellow marks the top three months on the Balanced mix. September stays as your reference.
No other scored month has a Weather score at least 1.0 point higher than September.
Your comparison
Overnight stays are 100% of the busiest month.
National hotel prices and local visitor demand suggest well above usual. No measured regional room rate is available.
Read the August guide →| Typical conditions | September | August |
|---|---|---|
| Afternoons | 73°F | 83°F |
| Nights | 54°F | 60°F |
| Sea | 73°F | 78°F |
| Rain days | 10 | 9 |
| Visitor season | Moderate season | Peak season |
| Overall / 10 | 7.7 | 6.3 |
| Month rank | #4 | #12 |
| Month | Overall | Rank | High | Low | Sea | Rain days | Weather | Visitor season |
|---|---|---|---|---|---|---|---|---|
| January | 6.8 | #9 | 44°F | 30°F | 52°F | 8 | 4.8 | Low season |
| February | 6.8 | #10 | 47°F | 31°F | 50°F | 7 | 4.8 | Low season |
| March | 7.5 | #6 | 56°F | 36°F | 51°F | 8 | 6.1 | Low season |
| April | 7.9 | #1 | 64°F | 43°F | 56°F | 8 | 7.5 | Low season |
| May | 7.8 | #2 | 70°F | 50°F | 64°F | 12 | 8.0 | Moderate season |
| June | 7.7 | #3 | 79°F | 59°F | 73°F | 10 | 8.5 | Moderate season |
| July | 6.5 | #11 | 83°F | 61°F | 78°F | 11 | 7.8 | Peak season |
| August | 6.3 | #12 | 83°F | 60°F | 78°F | 9 | 7.9 | Peak season |
| September | 7.7 | #4 | 73°F | 54°F | 73°F | 10 | 8.3 | Moderate season |
| October | 7.7 | #5 | 63°F | 46°F | 67°F | 9 | 7.2 | Low season |
| November | 7.1 | #7 | 52°F | 39°F | 62°F | 11 | 5.1 | Low season |
| December | 6.8 | #8 | 46°F | 31°F | 57°F | 8 | 4.9 | Low season |
Near here
Nearby regions, nearest first. Distances are centre to centre, as the crow flies; they are not road distances or journey times.
CarinthiaAustria · about 50 miles
Balanced Overall 7.4 · Very good weather, 69°F (21°C) · Moderate season · Cost pricey
Friuli Venezia GiuliaItaly · about 50 miles
Balanced Overall 7.1 · Very good weather, 76°F (24°C) · Moderate season · Cost pricey
Venice & the VenetoItaly · about 110 miles
Balanced Overall 7.2 · Very good weather, 77°F (25°C) · Busy season · Cost pricey
Croatia's coastSplit, Dubrovnik · Croatia · about 140 miles
Balanced Overall 7.6 · Very good weather, 77°F (25°C) · Moderate season · Cost pricey
Munich & Upper BavariaGermany · about 180 miles
Balanced Overall 6.8 · Very good weather, 69°F (20°C) · Busy season · Cost pricey
Elsewhere in Europe
Ljubljana, Lake Bled & western Slovenia's weather ranks 15 of 28 mountain regions this month. These mountain regions outside Slovenia have clearly better weather on your dates, nearest first, each compared with Ljubljana, Lake Bled & western Slovenia.
It's moderate season, 53% of the busiest month and 29% above its average month. That means about 42,000 overnight visitors on a typical September night across the region, 15% of them from Slovenia itself. Rentals booked through Airbnb, Booking, Expedia and Tripadvisor add up to 13,000 more: 31 for every 100 counted above. Some are the same properties counted twice.
| Climate suitability (HCI:Urban, 0–100) | 77 |
| How our weather was checked | Official climate averages for Ljubljana Bezigrad from the national weather service, every month: afternoon highs typically within 1°F (0.8°C), night lows within 1°F (0.4°C). |
| Tourist nights per 1,000 residents per day | 41 |
| Busiest month here | August · 78 |
| Visitors as share of people present | 4.0% |
| Rank among Europe's regions this month | 86th percentile |
| Domestic share of nights | 15% |
| Platform rental nights per 100 counted nights | 31 |
| Visitor share if every platform night were extra | 5.1% |
| National hotel-price season | Slovenia historical 2024–2025 index: A little above usual (+6% vs its average month). Not a local room quote. |
| Population used | 1.0 million |
| Statistical region | SI04 · Zahodna Slovenija |
Crowds: Eurostat nights spent at tourist accommodation, by month and NUTS 2 region, 2024–2025 average. Overnight visitors per night is the month's nights divided by its days; the per-1,000 figure is Eurostat's, against each year's population. Platform rentals: Eurostat nights booked via Airbnb, Booking, Expedia and Tripadvisor, 2024–2025 average, shown separately because some properties are in both counts. Weather: Holiday Climate Index computed from ERA5 reanalysis with daily highs, night lows and rain days corrected from open national weather-service station records, 2011–2025, population-weighted to the region; day-by-day figures are the same data averaged by date. Heat and rain odds are counted across those years. Sunrise and sunset: NOAA solar equations, local time. Prices: Eurostat price level index and HICP, national. Full method · this region's data.