09.08
tue
tue
DAY

92°F
E 5 mph
precip
1%
1%
NIGHT

72°F
W 4 mph
precip
36%
36%
09.09
wed
wed
DAY

76°F
W 4 mph
precip
70%
70%
NIGHT

70°F
SE 9 mph
precip
87%
87%
09.10
thu
thu
DAY

80°F
SW 3 mph
precip
26%
26%
NIGHT

70°F
S 3 mph
precip
39%
39%
09.11
fri
fri
DAY

78°F
S 2 mph
precip
18%
18%
NIGHT

68°F
W 3 mph
precip
26%
26%
09.12
sat
sat
DAY

78°F
NW 1 mph
precip
17%
17%
NIGHT

62°F
W 4 mph
precip
6%
6%
09.13
sun
sun
DAY

76°F
NW 5 mph
precip
1%
1%
NIGHT

64°F
W 4 mph
precip
18%
18%
09.14
mon
mon
DAY

72°F
SW 4 mph
precip
13%
13%
NIGHT

64°F
W 6 mph
precip
6%
6%
Weather in
September
September
| Portoroz |
14 day weather
forecast
forecast
| Portoroz |
Monthly weather
averages
averages
| Portoroz |
Sea water
temperature
temperature
| Portoroz |
Portoroz Sea Water Temperature in September, °F
The average sea surface temperature in September 2025 for Portoroz was 24.1°F. The maximum and minimum values were 22.8°F and 25.1°F respectively.
Slovenia Resorts:
NAME
F°
| Bled | ![]() |
+62 |
| Bohinjsko Jezero | ![]() |
+62 |
| Bovec | ![]() |
+74 |
| Cerkno | ![]() |
+64 |
| Dolenjske Toplice | ![]() |
+74 |
| Isola | ![]() |
+76 |
| Koper | ![]() |
+76 |
| Ljubljana | ![]() |
+72 |
| Maribor | ![]() |
+76 |
| Moravske Toplice | ![]() |
+78 |
| Piran | ![]() |
+76 |
| Portoroz | ![]() |
+76 |
| Rogaska Slatina | ![]() |
+72 |
| Smarjeske Toplice | ![]() |
+74 |
| Strunjan | ![]() |
+76 |


























