Climate - Postojna (Slovenia)

The climate of Postojna is moderately continental, with cold winters and warm summers.
The city is located in the Karst hills, at 530 meters (1,700 feet) above sea level, and 30 km (18 mi) north-east of Trieste.
The cold record is -26.4 °C (-15.5 °F), set in January 1968. The heat record is 36.4 °C (97.5 °F), set in August 2013.
The average temperature of the coldest month (January) is of 0.7 °C (33 °F), that of the warmest month (August) is of 19.6 °C (67 °F). Here are the average temperatures.

Precipitation amounts to 1,525 millimeters (60 inches) per year: it is therefore abundant. It ranges from 90 mm (3.5 in) in the driest month (January) to 185 mm (7.3 in) in the wettest (November). Here is the average precipitation.

On average, there are around 2,000 sunshine hours per year. Here are the average sunshine hours per day.

Weather by month

Based on the period 1991 - 2020.
(January - February - March - April - May - June - July - August - September - October - November - December)

In January, the coldest month of the year, the average temperature is 0.7 °C (33.2 °F), with a minimum of -2.8 °C (27 °F) and a maximum of 4.1 °C (39.4 °F).
On the coldest nights of the month, the temperature typically drops to -11 °C (13 °F). However, it dropped to -17 °C (2 °F) in January 2000.
On the mildest days of the month, the temperature typically reaches 11.5 °C (52 °F). However, it reached 15.5 °C (60 °F) in January 2013.
Precipitation amounts to 90 millimeters (3.5 inches), spread over 8 days.
On average, there are 93 hours of sunshine per month, ie 3 hours per day.

In February, the average temperature is 1.7 °C (35.1 °F), with a minimum of -2.6 °C (27.3 °F) and a maximum of 6.1 °C (42.9 °F).
On the coldest nights of the month, the temperature typically drops to -10.5 °C (13 °F). However, it dropped to -15.5 °C (4 °F) in February 2018.
On the mildest days of the month, the temperature typically reaches 13.5 °C (57 °F). However, it reached 21 °C (70 °F) in February 1998.
Precipitation amounts to 105 millimeters (4.1 inches), spread over 8 days.
On average, there are 114 hours of sunshine per month, ie 4.1 hours per day.

In March, the average temperature is 5.4 °C (41.6 °F), with a minimum of 0.4 °C (32.7 °F) and a maximum of 10.3 °C (50.6 °F).
On the coldest nights of the month, the temperature typically drops to -7 °C (19 °F). However, it dropped to -19.5 °C (-3 °F) in March 2005.
On the mildest days of the month, the temperature typically reaches 18 °C (64 °F). However, it reached 22 °C (72 °F) in March 2019.
Precipitation amounts to 100 millimeters (3.9 inches), spread over 8 days.
On average, there are 159 hours of sunshine per month, ie 5.1 hours per day.

In April, the average temperature is 9.2 °C (48.5 °F), with a minimum of 3.7 °C (38.6 °F) and a maximum of 14.7 °C (58.5 °F).
On the coldest nights of the month, the temperature typically drops to -3 °C (26 °F). However, it dropped to -9 °C (15 °F) in April 2003.
On the warmest days of the month, the temperature typically reaches 22 °C (72 °F). However, it reached 28 °C (82 °F) in April 2012.
Precipitation amounts to 115 millimeters (4.5 inches), spread over 11 days.
On average, there are 176 hours of sunshine per month, ie 5.9 hours per day.

In May, the average temperature is 13.6 °C (56.5 °F), with a minimum of 7.7 °C (45.9 °F) and a maximum of 19.5 °C (67.1 °F).
On the coldest nights of the month, the temperature typically drops to 1.5 °C (35 °F). However, it dropped to -1.5 °C (29 °F) in May 2019.
On the warmest days of the month, the temperature typically reaches 26.5 °C (79 °F). However, it reached 31.5 °C (89 °F) in May 2009.
Precipitation amounts to 130 millimeters (5.1 inches), spread over 11 days.
On average, there are 212 hours of sunshine per month, ie 6.8 hours per day.

In June, the average temperature is 17.5 °C (63.5 °F), with a minimum of 11.4 °C (52.5 °F) and a maximum of 23.6 °C (74.4 °F).
On the coldest nights of the month, the temperature typically drops to 6 °C (43 °F). However, it dropped to 1.5 °C (35 °F) in June 2019.
On the warmest days of the month, the temperature typically reaches 30 °C (86 °F). However, it reached 34.5 °C (94 °F) in June 2019.
Precipitation amounts to 120 millimeters (4.7 inches), spread over 10 days.
On average, there are 229 hours of sunshine per month, ie 7.6 hours per day.

In July, the average temperature is 19.5 °C (67.1 °F), with a minimum of 13 °C (55.4 °F) and a maximum of 26 °C (78.8 °F).
On the coldest nights of the month, the temperature typically drops to 7.5 °C (46 °F). However, it dropped to 3.5 °C (38 °F) in July 1993.
On the warmest days of the month, the temperature typically reaches 31.5 °C (89 °F). However, it reached 35 °C (95 °F) in July 2006.
Precipitation amounts to 100 millimeters (3.9 inches), spread over 8 days.
On average, there are 270 hours of sunshine per month, ie 8.7 hours per day.

In August, the warmest month of the year, the average temperature is 19.6 °C (67.2 °F), with a minimum of 13 °C (55.4 °F) and a maximum of 26.1 °C (79 °F).
On the coldest nights of the month, the temperature typically drops to 6.5 °C (44 °F). However, it dropped to 3 °C (37 °F) in August 1995.
On the warmest days of the month, the temperature typically reaches 31.5 °C (88 °F). However, it reached 36.5 °C (98 °F) in August 2013.
Precipitation amounts to 110 millimeters (4.3 inches), spread over 8 days.
On average, there are 266 hours of sunshine per month, ie 8.6 hours per day.

In September, the average temperature is 15 °C (58.9 °F), with a minimum of 9.6 °C (49.3 °F) and a maximum of 20.3 °C (68.6 °F).
On the coldest nights of the month, the temperature typically drops to 3 °C (37 °F). However, it dropped to -2 °C (28 °F) in September 1995.
On the warmest days of the month, the temperature typically reaches 26 °C (79 °F). However, it reached 31 °C (88 °F) in September 2011.
Precipitation amounts to 160 millimeters (6.3 inches), spread over 10 days.
On average, there are 184 hours of sunshine per month, ie 6.1 hours per day.

In October, the average temperature is 10.7 °C (51.3 °F), with a minimum of 6.5 °C (43.7 °F) and a maximum of 15 °C (59 °F).
On the coldest nights of the month, the temperature typically drops to -2 °C (28 °F). However, it dropped to -9.5 °C (15 °F) in October 2003.
On the warmest days of the month, the temperature typically reaches 21.5 °C (70 °F). However, it reached 26 °C (79 °F) in October 2017.
Precipitation amounts to 165 millimeters (6.5 inches), spread over 11 days.
On average, there are 136 hours of sunshine per month, ie 4.4 hours per day.

In November, the average temperature is 6.1 °C (42.9 °F), with a minimum of 2.7 °C (36.8 °F) and a maximum of 9.4 °C (49 °F).
On the coldest nights of the month, the temperature typically drops to -6.5 °C (20 °F). However, it dropped to -15.5 °C (4 °F) in November 1999.
On the mildest days of the month, the temperature typically reaches 16.5 °C (62 °F). However, it reached 23.5 °C (75 °F) in November 2015.
Precipitation amounts to 185 millimeters (7.3 inches), spread over 12 days.
On average, there are 81 hours of sunshine per month, ie 2.7 hours per day.

In December, the average temperature is 1.4 °C (34.6 °F), with a minimum of -2 °C (28.3 °F) and a maximum of 4.9 °C (40.9 °F).
On the coldest nights of the month, the temperature typically drops to -11.5 °C (11 °F). However, it dropped to -19 °C (-2 °F) in December 2010.
On the mildest days of the month, the temperature typically reaches 12 °C (53 °F). However, it reached 15.5 °C (60 °F) in December 2016.
Precipitation amounts to 140 millimeters (5.5 inches), spread over 10 days.
On average, there are 79 hours of sunshine per month, ie 2.6 hours per day.

Best Time

The best time to visit Postojna runs from mid-May to mid-September, since it is the warmest and sunniest period of the year. Sometimes, it can be hot in July and August, while in other circumstances, nights can be cool or even a little cold even in these months, so it can be useful to bring a sweatshirt or sweater and a light jacket for the evening.