Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Portoroz-Letalisce. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Portoroz-Letalisce, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
18.2 C (64.8 F)
-9.5 C (14.9 F)
n/a
n/a
Feb
22.2 C (72.0 F)
-10.3 C (13.5 F)
n/a
n/a
Mar
23.2 C (73.8 F)
-10.5 C (13.1 F)
n/a
n/a
Apr
28.2 C (82.8 F)
-4.2 C (24.4 F)
n/a
n/a
May
33.2 C (91.8 F)
3.3 C (37.9 F)
n/a
n/a
Jun
35.6 C (96.1 F)
6.4 C (43.5 F)
n/a
n/a
Jul
37.4 C (99.3 F)
8.8 C (47.8 F)
n/a
n/a
Aug
37.3 C (99.1 F)
7.5 C (45.5 F)
n/a
n/a
Sep
33.0 C (91.4 F)
4.8 C (40.6 F)
n/a
n/a
Oct
27.5 C (81.5 F)
-1.8 C (28.8 F)
n/a
n/a
Nov
24.4 C (75.9 F)
-5.0 C (23.0 F)
n/a
n/a
Dec
19.1 C (66.4 F)
-9.9 C (14.2 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Portoroz-Letalisce still stand. 1991 holds the most, with 71.
Standing records at Portoroz-Letalisce by the year they were set
Year set
Standing records
1987
51
1988
19
1989
41
1990
43
1991
71
1992
27
1993
49
1994
42
1995
27
1996
51
1997
37
1998
36
1999
30
2000
44
2001
46
2002
39
2003
53
2004
17
2005
39
2006
43
2007
41
2008
37
2009
46
2010
26
2011
35
2012
47
2013
42
2014
56
2015
35
2016
37
2017
30
2018
56
2019
46
2020
38
2021
26
2022
30
2023
31
All-Time Record Progression
1 new records
1 all-time records were set at Portoroz-Letalisce between 3 August 2018 and 3 August 2018. Each dot is a new record.
When Portoroz-Letalisce set new all-time records
Date
Kind
Detail
2018-08-03
Record high minimum temperature
Record high minimum temperature 26.3 C (79.3 F)
Wettest Day of Each Month
Sep: 136.5 mm (5.4 in)
The wettest day on record for each calendar month at Portoroz-Letalisce. The most was 136.5 mm (5.4 in) on 21 September 1996.
Record daily precipitation for each month at Portoroz-Letalisce
Month
Record daily precipitation (mm)
Date
Jan
57.7 mm (2.3 in)
8 January 2001
Feb
52.4 mm (2.1 in)
12 February 2007
Mar
45.4 mm (1.8 in)
24 March 1992
Apr
57.5 mm (2.3 in)
21 April 2014
May
59.7 mm (2.4 in)
30 May 2010
Jun
76.3 mm (3.0 in)
20 June 2009
Jul
130.9 mm (5.2 in)
29 July 2010
Aug
131.0 mm (5.2 in)
28 August 2023
Sep
136.5 mm (5.4 in)
21 September 1996
Oct
97.5 mm (3.8 in)
10 October 2000
Nov
108.8 mm (4.3 in)
20 November 2016
Dec
88.1 mm (3.5 in)
6 December 2020
Period of Record Coverage
1987 to 2023
Complete yearUnder 90 percent of days
37 years of record at Portoroz-Letalisce, 1987 to 2023. 3 years have data for under 90 percent of days and are left out of rankings: 1987, 1988, 2023.
Cooler than the station meanWarmer than the station mean
One stripe for each of 34 complete years at Portoroz-Letalisce, 1989 to 2022. Blue stripes are years cooler than the station's own mean of 14.1 C (57.4 F); red stripes are warmer. The coolest year was 1991, at 12.8 C (55.0 F), and the warmest was 2018, at 15.3 C (59.5 F). The strongest colour marks a difference of 1.4 C (2.5 F).
Annual mean temperature at Portoroz-Letalisce as warming stripes, 1989 to 2022
Year
Annual mean temperature
Difference from the station mean
1989
13.2 C
-0.90 C
1990
13.6 C
-0.55 C
1991
12.8 C
-1.32 C
1992
13.6 C
-0.52 C
1993
13.4 C
-0.73 C
1994
14.5 C
+0.36 C
1995
13.3 C
-0.85 C
1996
13.1 C
-1.02 C
1997
13.7 C
-0.38 C
1998
13.6 C
-0.49 C
1999
14.0 C
-0.14 C
2000
14.4 C
+0.27 C
2001
14.2 C
+0.13 C
2002
14.3 C
+0.16 C
2003
14.1 C
+0.02 C
2004
13.5 C
-0.58 C
2005
13.0 C
-1.14 C
2006
14.0 C
-0.09 C
2007
14.6 C
+0.45 C
2008
14.3 C
+0.17 C
2009
14.5 C
+0.37 C
2010
13.5 C
-0.62 C
2011
14.4 C
+0.27 C
2012
14.3 C
+0.24 C
2013
14.4 C
+0.27 C
2014
15.2 C
+1.11 C
2015
14.7 C
+0.59 C
2016
14.7 C
+0.58 C
2017
14.4 C
+0.29 C
2018
15.3 C
+1.15 C
2019
15.1 C
+1.01 C
2020
14.8 C
+0.69 C
2021
14.2 C
+0.08 C
2022
15.2 C
+1.10 C
The annual mean temperature here has risen by 0.5 C (0.4 to 0.7) per decade over 1989 to 2022. In Fahrenheit: 0.9 F (0.6 to 1.2) per decade. The slope is a straight line fitted to 34 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Portoroz-Letalisce
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.5 C (0.4 to 0.7) per decade
0.9 F (0.6 to 1.2) per decade
1989 to 2022
34
Rise
Mean daily maximum
0.5 C (0.4 to 0.7) per decade
1.0 F (0.6 to 1.3) per decade
1989 to 2022
34
Rise
Mean daily minimum
0.5 C (0.3 to 0.7) per decade
0.9 F (0.6 to 1.2) per decade
1989 to 2022
34
Rise
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1986 to 2023
Yearly extremes at Portoroz-Letalisce: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
37.4 C (99.3 F)
2015
34.9 C (94.8 F)
37
Coldest night (TNn)
-10.5 C (13.1 F)
2005
-6.4 C (20.5 F)
37
Wettest day (Rx1day)
136.5 mm (5.4 in)
1996
58.4 mm (2.3 in)
38
Wettest five days (Rx5day)
211.1 mm (8.3 in)
2023
102.1 mm (4.0 in)
37
Longest dry spell (CDD)
75 days
1998
31 days
38
Hottest day (TXx)
The hottest day of the year at Portoroz-Letalisce, 1986 to 2023. The record is 37.4 C (99.3 F) in 2015, marked on the chart; the median year is 34.9 C (94.8 F).
Hottest day (TXx) at Portoroz-Letalisce by year
Year
Hottest day (TXx)
1986
n/a
1987
33.6 C (92.5 F)
1988
34.2 C (93.6 F)
1989
33.0 C (91.4 F)
1990
34.9 C (94.8 F)
1991
33.6 C (92.5 F)
1992
34.7 C (94.5 F)
1993
34.1 C (93.4 F)
1994
35.7 C (96.3 F)
1995
34.4 C (93.9 F)
1996
34.4 C (93.9 F)
1997
31.4 C (88.5 F)
1998
36.3 C (97.3 F)
1999
33.0 C (91.4 F)
2000
35.0 C (95.0 F)
2001
34.7 C (94.5 F)
2002
34.0 C (93.2 F)
2003
36.9 C (98.4 F)
2004
34.9 C (94.8 F)
2005
34.6 C (94.3 F)
2006
35.9 C (96.6 F)
2007
36.7 C (98.1 F)
2008
33.5 C (92.3 F)
2009
33.8 C (92.8 F)
2010
35.5 C (95.9 F)
2011
35.1 C (95.2 F)
2012
36.8 C (98.2 F)
2013
37.3 C (99.1 F)
2014
33.6 C (92.5 F)
2015
37.4 C (99.3 F)
2016
34.5 C (94.1 F)
2017
37.3 C (99.1 F)
2018
35.4 C (95.7 F)
2019
35.6 C (96.1 F)
2020
34.8 C (94.6 F)
2021
35.1 C (95.2 F)
2022
37.2 C (99.0 F)
2023
35.7 C (96.3 F)
Coldest night (TNn)
The coldest night of the year at Portoroz-Letalisce, 1986 to 2023. The record is -10.5 C (13.1 F) in 2005, marked on the chart; the median year is -6.4 C (20.5 F).
Coldest night (TNn) at Portoroz-Letalisce by year
Year
Coldest night (TNn)
1986
n/a
1987
-9.0 C (15.8 F)
1988
-5.5 C (22.1 F)
1989
-6.9 C (19.6 F)
1990
-5.0 C (23.0 F)
1991
-10.3 C (13.5 F)
1992
-6.2 C (20.8 F)
1993
-6.8 C (19.8 F)
1994
-8.2 C (17.2 F)
1995
-6.4 C (20.5 F)
1996
-8.5 C (16.7 F)
1997
-4.4 C (24.1 F)
1998
-6.3 C (20.7 F)
1999
-5.5 C (22.1 F)
2000
-9.5 C (14.9 F)
2001
-7.8 C (18.0 F)
2002
-7.5 C (18.5 F)
2003
-8.8 C (16.2 F)
2004
-8.6 C (16.5 F)
2005
-10.5 C (13.1 F)
2006
-8.6 C (16.5 F)
2007
-3.6 C (25.5 F)
2008
-6.7 C (19.9 F)
2009
-9.9 C (14.2 F)
2010
-7.4 C (18.7 F)
2011
-5.7 C (21.7 F)
2012
-8.1 C (17.4 F)
2013
-3.8 C (25.2 F)
2014
-2.0 C (28.4 F)
2015
-3.5 C (25.7 F)
2016
-4.6 C (23.7 F)
2017
-8.7 C (16.3 F)
2018
-5.9 C (21.4 F)
2019
-4.4 C (24.1 F)
2020
-2.2 C (28.0 F)
2021
-5.1 C (22.8 F)
2022
-4.0 C (24.8 F)
2023
-5.4 C (22.3 F)
Wettest day (Rx1day)
The wettest day of the year at Portoroz-Letalisce, 1986 to 2023. The record is 136.5 mm (5.4 in) in 1996, marked on the chart; the median year is 58.4 mm (2.3 in).
Wettest day (Rx1day) at Portoroz-Letalisce by year
Year
Wettest day (Rx1day)
1986
0.0 mm (0.00 in)
1987
38.6 mm (1.5 in)
1988
77.7 mm (3.1 in)
1989
50.5 mm (2.0 in)
1990
59.7 mm (2.4 in)
1991
72.7 mm (2.9 in)
1992
48.3 mm (1.9 in)
1993
56.6 mm (2.2 in)
1994
49.5 mm (1.9 in)
1995
55.8 mm (2.2 in)
1996
136.5 mm (5.4 in)
1997
61.9 mm (2.4 in)
1998
54.5 mm (2.1 in)
1999
55.8 mm (2.2 in)
2000
97.5 mm (3.8 in)
2001
68.9 mm (2.7 in)
2002
68.9 mm (2.7 in)
2003
78.6 mm (3.1 in)
2004
55.1 mm (2.2 in)
2005
38.3 mm (1.5 in)
2006
95.0 mm (3.7 in)
2007
53.8 mm (2.1 in)
2008
54.1 mm (2.1 in)
2009
76.3 mm (3.0 in)
2010
130.9 mm (5.2 in)
2011
50.6 mm (2.0 in)
2012
54.3 mm (2.1 in)
2013
77.7 mm (3.1 in)
2014
113.5 mm (4.5 in)
2015
50.4 mm (2.0 in)
2016
108.8 mm (4.3 in)
2017
73.1 mm (2.9 in)
2018
57.1 mm (2.2 in)
2019
64.7 mm (2.5 in)
2020
88.1 mm (3.5 in)
2021
40.7 mm (1.6 in)
2022
39.8 mm (1.6 in)
2023
131.0 mm (5.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Portoroz-Letalisce, 1986 to 2023. The record is 211.1 mm (8.3 in) in 2023, marked on the chart; the median year is 102.1 mm (4.0 in).
Wettest five days (Rx5day) at Portoroz-Letalisce by year
Year
Wettest five days (Rx5day)
1986
n/a
1987
73.3 mm (2.9 in)
1988
105.5 mm (4.2 in)
1989
94.0 mm (3.7 in)
1990
95.3 mm (3.8 in)
1991
144.8 mm (5.7 in)
1992
90.8 mm (3.6 in)
1993
110.9 mm (4.4 in)
1994
92.4 mm (3.6 in)
1995
67.6 mm (2.7 in)
1996
174.0 mm (6.9 in)
1997
108.8 mm (4.3 in)
1998
102.1 mm (4.0 in)
1999
77.4 mm (3.0 in)
2000
137.6 mm (5.4 in)
2001
122.0 mm (4.8 in)
2002
135.3 mm (5.3 in)
2003
80.1 mm (3.2 in)
2004
99.7 mm (3.9 in)
2005
118.7 mm (4.7 in)
2006
134.1 mm (5.3 in)
2007
102.6 mm (4.0 in)
2008
69.5 mm (2.7 in)
2009
89.6 mm (3.5 in)
2010
155.3 mm (6.1 in)
2011
80.9 mm (3.2 in)
2012
95.0 mm (3.7 in)
2013
80.2 mm (3.2 in)
2014
127.2 mm (5.0 in)
2015
59.5 mm (2.3 in)
2016
140.0 mm (5.5 in)
2017
149.4 mm (5.9 in)
2018
74.6 mm (2.9 in)
2019
122.5 mm (4.8 in)
2020
170.5 mm (6.7 in)
2021
74.4 mm (2.9 in)
2022
86.4 mm (3.4 in)
2023
211.1 mm (8.3 in)
Longest dry spell (CDD)
The longest dry spell of the year at Portoroz-Letalisce, 1986 to 2023. The record is 75 days in 1998, marked on the chart; the median year is 31 days.
Longest dry spell (CDD) at Portoroz-Letalisce by year
Year
Longest dry spell (CDD)
1986
1 day
1987
26 days
1988
56 days
1989
52 days
1990
39 days
1991
29 days
1992
37 days
1993
49 days
1994
24 days
1995
25 days
1996
25 days
1997
41 days
1998
75 days
1999
21 days
2000
25 days
2001
28 days
2002
45 days
2003
30 days
2004
23 days
2005
33 days
2006
34 days
2007
31 days
2008
27 days
2009
18 days
2010
19 days
2011
32 days
2012
50 days
2013
34 days
2014
26 days
2015
40 days
2016
35 days
2017
29 days
2018
29 days
2019
29 days
2020
39 days
2021
24 days
2022
32 days
2023
34 days
Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.
Frost Dates and Growing Season
33 years with a frost
Across 33 years with a frost, the median last spring frost at Portoroz-Letalisce falls on 25 March and the median first autumn frost on 19 November, which leaves a median of 239 days between them.
Fitted over all years, the growing season changes by +4.0 days per decade at this station.
Frost dates and growing season at Portoroz-Letalisce
Measure
Median, all years
Earliest period
Recent period (1992 to 2022)
Recent against earliest
Fitted trend
Last spring frost
25 March
n/a
27 March
n/a
+0.2 days per decade
First autumn frost
19 November
n/a
20 November
n/a
+4.2 days per decade
Growing days
239 days
n/a
237 days
n/a
+4.0 days per decade
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
33 years, 1989 to 2022
A day with at least 62.4 mm (2.5 in) of rain is expected about once in 2 years. A day with at least 173.5 mm (6.8 in) of rain is expected about once in 100 years.
Rainfall return levels at Portoroz-Letalisce: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
62.4 mm (2.5 in)
5 years
83.6 mm (3.3 in)
10 years
100.6 mm (4.0 in)
25 years
126.0 mm (5.0 in)
50 years
148.2 mm (5.8 in)
Longer than the 33 years of record
100 years
173.5 mm (6.8 in)
Longer than the 33 years of record
The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 33 years of values from 1989 to 2022.
A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.
The largest wettest-day totals in the fit: 136.5 mm (5.4 in) in 1996; 130.9 mm (5.2 in) in 2010; 113.5 mm (4.5 in) in 2014.
Download the Data
Data for Portoroz-Letalisce standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Portoroz-Letalisce threshold days by year: CSV or JSON. Field meanings are on the data page.
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.