Sion 2 Weather Records (SZE00105086)

Record envelope, standing records and threshold days for Sion 2 (SZE00105086), Switzerland, with 126 years of record.

Key Facts for Sion 2

Sion 2 (SZE00105086) is a weather station in Switzerland at 46.22 latitude and 7.33 longitude, 482 m (1,581 ft) above sea level.
The station reports from 1901 to 2026, 126 years of record.
1,464 records set at Sion 2 still stand.
Records are tracked for tmax, tmin, prcp, snwd: an element needs 30 years of data to be eligible.
Sion 2 set a daily record high minimum temperature of 19.2 C (66.6 F) on 20 August 2026 (provisional).

Provisional Records

Records set in the last 60 days are provisional until they clear the revision window.

About the Station

Location: Switzerland, 46.22 latitude, 7.33 longitude.
Elevation: 482 m (1,581 ft).
Period of record: 1901 to 2026, 126 years.
Eligible elements: tmax, tmin, prcp, snwd.

Daily Record Envelope and 2026

19 days at or beyond a record

The band shows the record high and record low for each calendar day at Sion 2. The lines show the 2026 daily maximum and minimum. 19 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Sion 2, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	16.8 C (62.2 F)	-20.6 C (-5.1 F)	13.7 C (56.7 F)	-11.9 C (10.6 F)
Feb	21.4 C (70.5 F)	-17.2 C (1.0 F)	19.4 C (66.9 F)	-3.8 C (25.2 F)
Mar	26.6 C (79.9 F)	-12.8 C (9.0 F)	19.0 C (66.2 F)	-3.2 C (26.2 F)
Apr	30.2 C (86.4 F)	-7.2 C (19.0 F)	25.7 C (78.3 F)	-1.8 C (28.8 F)
May	35.1 C (95.2 F)	-2.2 C (28.0 F)	34.2 C (93.6 F)	1.8 C (35.2 F)
Jun	37.0 C (98.6 F)	1.5 C (34.7 F)	36.8 C (98.2 F)	9.3 C (48.7 F)
Jul	38.0 C (100.4 F)	2.9 C (37.2 F)	29.3 C (84.7 F)	12.6 C (54.7 F)
Aug	37.6 C (99.7 F)	3.9 C (39.0 F)	37.5 C (99.5 F)	10.7 C (51.3 F)
Sep	34.0 C (93.2 F)	0.0 C (32.0 F)	n/a	n/a
Oct	27.4 C (81.3 F)	-5.0 C (23.0 F)	n/a	n/a
Nov	21.1 C (70.0 F)	-13.4 C (7.9 F)	n/a	n/a
Dec	17.5 C (63.5 F)	-17.8 C (0.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Sion 2 still stand. 1956 holds the most, with 46.

Standing records at Sion 2 by the year they were set
Year set	Standing records
1955	30
1956	46
1957	30
1958	23
1959	10
1960	17
1961	26
1962	42
1963	28
1964	11
1965	17
1966	28
1967	19
1968	20
1969	25
1970	16
1971	31
1972	13
1973	20
1974	17
1975	28
1976	16
1977	22
1978	29
1979	29
1980	29
1981	29
1982	19
1983	26
1984	17
1985	41
1986	10
1987	16
1988	12
1989	12
1990	10
1991	9
1992	10
1993	8
1994	15
1995	16
1996	16
1997	13
1998	8
1999	5
2000	9
2001	22
2002	22
2003	25
2004	8
2005	24
2006	22
2007	29
2008	10
2009	17
2010	6
2011	21
2012	31
2013	19
2014	24
2015	33
2016	15
2017	19
2018	28
2019	35
2020	10
2021	10
2022	30
2023	29
2024	15
2025	17
2026	20

All-Time Record Progression

9 new records

9 all-time records were set at Sion 2 between 23 December 1954 and 24 July 2019. Each dot is a new record.

When Sion 2 set new all-time records
Date	Kind	Detail
1954-12-23	Record daily precipitation	Record daily precipitation 65.6 mm (2.6 in)
1957-02-24	Record daily precipitation	Record daily precipitation 68.2 mm (2.7 in)
1971-11-21	Record daily precipitation	Record daily precipitation 81.3 mm (3.2 in)
2002-06-20	Record high minimum temperature	Record high minimum temperature 20.9 C (69.6 F)
2003-08-05	Record high maximum temperature	Record high maximum temperature 37.2 C (99.0 F)
2015-07-04	Record high minimum temperature	Record high minimum temperature 21.0 C (69.8 F)
2015-07-07	Record high maximum temperature	Record high maximum temperature 37.8 C (100.0 F)
2015-07-13	Record high minimum temperature	Record high minimum temperature 21.3 C (70.3 F)
2019-07-24	Record high maximum temperature	Record high maximum temperature 38.0 C (100.4 F)

Wettest Day of Each Month

Nov: 81.3 mm (3.2 in)

The wettest day on record for each calendar month at Sion 2. The most was 81.3 mm (3.2 in) on 21 November 1971.

Record daily precipitation for each month at Sion 2
Month	Record daily precipitation (mm)	Date
Jan	64.5 mm (2.5 in)	19 January 1910
Feb	79.3 mm (3.1 in)	14 February 1990
Mar	50.6 mm (2.0 in)	20 March 1978
Apr	72.8 mm (2.9 in)	16 April 2025
May	49.0 mm (1.9 in)	1 May 2015
Jun	47.5 mm (1.9 in)	21 June 1946
Jul	49.5 mm (1.9 in)	15 July 1922
Aug	57.9 mm (2.3 in)	6 August 2018
Sep	51.8 mm (2.0 in)	4 September 1948
Oct	47.5 mm (1.9 in)	11 October 1940
Nov	81.3 mm (3.2 in)	21 November 1971
Dec	65.6 mm (2.6 in)	23 December 1954

Period of Record Coverage

1955 to 2026

72 years of record at Sion 2, 1955 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1964, 2026.

Days with data per year at Sion 2
Year	Days with data	Share of year	Complete
1955	356	98%	Yes
1956	358	98%	Yes
1957	349	96%	Yes
1958	360	99%	Yes
1959	357	98%	Yes
1960	361	99%	Yes
1961	361	99%	Yes
1962	352	96%	Yes
1963	356	98%	Yes
1964	184	50%	No
1965	365	100%	Yes
1966	365	100%	Yes
1967	365	100%	Yes
1968	366	100%	Yes
1969	365	100%	Yes
1970	365	100%	Yes
1971	363	99%	Yes
1972	365	100%	Yes
1973	365	100%	Yes
1974	365	100%	Yes
1975	363	99%	Yes
1976	365	100%	Yes
1977	363	99%	Yes
1978	365	100%	Yes
1979	364	100%	Yes
1980	365	100%	Yes
1981	365	100%	Yes
1982	365	100%	Yes
1983	365	100%	Yes
1984	366	100%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	365	100%	Yes
1988	366	100%	Yes
1989	365	100%	Yes
1990	365	100%	Yes
1991	365	100%	Yes
1992	366	100%	Yes
1993	365	100%	Yes
1994	365	100%	Yes
1995	365	100%	Yes
1996	366	100%	Yes
1997	365	100%	Yes
1998	365	100%	Yes
1999	365	100%	Yes
2000	366	100%	Yes
2001	365	100%	Yes
2002	365	100%	Yes
2003	365	100%	Yes
2004	366	100%	Yes
2005	365	100%	Yes
2006	365	100%	Yes
2007	365	100%	Yes
2008	366	100%	Yes
2009	365	100%	Yes
2010	365	100%	Yes
2011	365	100%	Yes
2012	366	100%	Yes
2013	365	100%	Yes
2014	365	100%	Yes
2015	365	100%	Yes
2016	336	92%	Yes
2017	334	92%	Yes
2018	365	100%	Yes
2019	365	100%	Yes
2020	366	100%	Yes
2021	364	100%	Yes
2022	364	100%	Yes
2023	364	100%	Yes
2024	365	100%	Yes
2025	365	100%	Yes
2026	214	59%	No

Latest Records

Latest records at Sion 2
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
20 August 2026	Sion 2, CH	daily high min (Provisional)	19.2 C (66.6 F)	0.2 C (0.4 F)	13 years	11 of 100 (Routine)
19 August 2026	Sion 2, CH	daily high max (Provisional)	35.6 C (96.1 F)	0.1 C (0.2 F)	16 years	12 of 100 (Routine)
15 August 2026	Sion 2, CH	daily high max (Provisional)	35.8 C (96.4 F)	1.9 C (3.4 F)	13 years	15 of 100 (Routine)
14 August 2026	Sion 2, CH	daily high max	37.0 C (98.6 F)	3.0 C (5.4 F)	3 years	14 of 100 (Routine)
13 August 2026	Sion 2, CH	daily high max	37.5 C (99.5 F)	0.3 C (0.5 F)	23 years	13 of 100 (Routine)
13 August 2026	Sion 2, CH	daily high min (Tie)	18.5 C (65.3 F)	tie	11 years	2 of 100 (Routine)
28 June 2026	Sion 2, CH	daily high min	19.4 C (66.9 F)	0.8 C (1.4 F)	7 years	11 of 100 (Routine)
27 June 2026	Sion 2, CH	daily high min	19.4 C (66.9 F)	0.5 C (0.9 F)	56 years	24 of 100 (Routine)
27 June 2026	Sion 2, CH	daily high max (Tie)	36.8 C (98.2 F)	tie	7 years	2 of 100 (Routine)
24 June 2026	Sion 2, CH	daily high max	36.1 C (97.0 F)	2.3 C (4.1 F)	9 years	14 of 100 (Routine)
22 June 2026	Sion 2, CH	daily high max	36.1 C (97.0 F)	1.3 C (2.3 F)	8 years	11 of 100 (Routine)
21 June 2026	Sion 2, CH	daily high max	35.2 C (95.4 F)	1.2 C (2.2 F)	8 years	11 of 100 (Routine)
2 June 2026	Sion 2, CH	daily rain	17.9 mm (0.7 in)	4.1 mm (0.16 in)	88 years	20 of 100 (Routine)
31 May 2026	Sion 2, CH	daily high max	32.4 C (90.3 F)	2.2 C (4.0 F)	23 years	17 of 100 (Routine)
29 May 2026	Sion 2, CH	daily high max	33.4 C (92.1 F)	1.8 C (3.2 F)	8 years	13 of 100 (Routine)
28 May 2026	Sion 2, CH	daily high max	33.0 C (91.4 F)	0.8 C (1.4 F)	69 years	28 of 100 (Routine)
27 May 2026	Sion 2, CH	daily high max	34.2 C (93.6 F)	2.4 C (4.3 F)	8 years	14 of 100 (Routine)
27 May 2026	Sion 2, CH	daily high min	14.9 C (58.8 F)	0.6 C (1.1 F)	8 years	10 of 100 (Routine)
26 May 2026	Sion 2, CH	daily high max	33.9 C (93.0 F)	2.9 C (5.2 F)	15 years	17 of 100 (Routine)
26 May 2026	Sion 2, CH	daily high min (Tie)	15.0 C (59.0 F)	tie	15 years	2 of 100 (Routine)

Climate Trend

66 complete years, 1955 to 2025

One stripe for each of 66 complete years at Sion 2, 1955 to 2025. Blue stripes are years cooler than the station's own mean of 10.6 C (51.0 F); red stripes are warmer. The coolest year was 1956, at 8.1 C (46.6 F), and the warmest was 2018, at 12.8 C (55.1 F). The strongest colour marks a difference of 2.5 C (4.5 F).

Annual mean temperature at Sion 2 as warming stripes, 1955 to 2025
Year	Annual mean temperature	Difference from the station mean
1955	9.2 C	-1.40 C
1956	8.1 C	-2.46 C
1957	9.5 C	-1.11 C
1958	9.6 C	-0.95 C
1959	10.6 C	+0.01 C
1961	10.6 C	-0.01 C
1963	9.1 C	-1.47 C
1965	9.8 C	-0.74 C
1966	11.0 C	+0.44 C
1967	11.0 C	+0.46 C
1968	10.8 C	+0.20 C
1969	10.2 C	-0.33 C
1970	10.4 C	-0.17 C
1971	10.8 C	+0.19 C
1972	10.8 C	+0.25 C
1973	10.4 C	-0.17 C
1974	11.0 C	+0.38 C
1975	11.0 C	+0.41 C
1976	10.9 C	+0.31 C
1977	10.5 C	-0.06 C
1978	8.6 C	-1.99 C
1979	9.3 C	-1.23 C
1980	8.6 C	-2.01 C
1981	9.2 C	-1.37 C
1982	9.5 C	-1.03 C
1983	9.3 C	-1.27 C
1984	9.1 C	-1.49 C
1985	8.9 C	-1.64 C
1986	9.7 C	-0.90 C
1987	9.5 C	-1.07 C
1988	10.5 C	-0.06 C
1989	10.4 C	-0.15 C
1990	10.6 C	-0.02 C
1991	10.0 C	-0.58 C
1992	10.6 C	-0.02 C
1993	10.7 C	+0.10 C
1994	11.5 C	+0.93 C
1995	10.6 C	+0.01 C
1996	10.3 C	-0.28 C
1997	11.0 C	+0.46 C
1998	10.6 C	+0.03 C
1999	10.5 C	-0.09 C
2000	11.1 C	+0.54 C
2001	10.7 C	+0.13 C
2002	11.3 C	+0.74 C
2003	11.8 C	+1.19 C
2004	10.8 C	+0.26 C
2005	10.1 C	-0.48 C
2006	10.9 C	+0.34 C
2007	11.1 C	+0.54 C
2008	11.1 C	+0.51 C
2009	10.9 C	+0.28 C
2010	10.3 C	-0.23 C
2011	11.7 C	+1.16 C
2012	11.3 C	+0.77 C
2013	10.8 C	+0.25 C
2014	12.2 C	+1.64 C
2015	11.9 C	+1.32 C
2018	12.8 C	+2.25 C
2019	12.2 C	+1.62 C
2020	12.0 C	+1.39 C
2021	10.5 C	-0.07 C
2022	12.3 C	+1.72 C
2023	12.0 C	+1.44 C
2024	12.0 C	+1.40 C
2025	12.0 C	+1.41 C

The annual mean temperature here has risen by 0.3 C (0.2 to 0.4) per decade over 1955 to 2025. In Fahrenheit: 0.6 F (0.4 to 0.8) per decade. The slope is a straight line fitted to 66 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Sion 2
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.3 C (0.2 to 0.4) per decade	0.6 F (0.4 to 0.8) per decade	1955 to 2025	66	Rise
Mean daily maximum	0.4 C (0.3 to 0.5) per decade	0.6 F (0.5 to 0.8) per decade	1955 to 2025	66	Rise
Mean daily minimum	0.3 C (0.2 to 0.4) per decade	0.5 F (0.3 to 0.7) per decade	1955 to 2025	66	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

1901 to 2026

Yearly extremes at Sion 2: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	38.0 C (100.4 F)	2019	33.9 C (93.0 F)	72
Coldest night (TNn)	-20.6 C (-5.1 F)	1979	-11.5 C (11.2 F)	72
Wettest day (Rx1day)	81.3 mm (3.2 in)	1971	35.6 mm (1.4 in)	126
Wettest five days (Rx5day)	196.3 mm (7.7 in)	1990	63.6 mm (2.5 in)	126
Longest dry spell (CDD)	64 days	1920	27 days	126

Hottest day (TXx)

The hottest day of the year at Sion 2, 1901 to 2026. The record is 38.0 C (100.4 F) in 2019, marked on the chart; the median year is 33.9 C (93.0 F).

Hottest day (TXx) at Sion 2 by year
Year	Hottest day (TXx)
1901	n/a
1902	n/a
1903	n/a
1904	n/a
1905	n/a
1906	n/a
1907	n/a
1908	n/a
1909	n/a
1910	n/a
1911	n/a
1912	n/a
1913	n/a
1914	n/a
1915	n/a
1916	n/a
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	n/a
1934	n/a
1935	n/a
1936	n/a
1937	n/a
1938	n/a
1939	n/a
1940	n/a
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	32.2 C (90.0 F)
1956	32.2 C (90.0 F)
1957	33.9 C (93.0 F)
1958	33.9 C (93.0 F)
1959	32.2 C (90.0 F)
1960	31.1 C (88.0 F)
1961	32.2 C (90.0 F)
1962	33.9 C (93.0 F)
1963	32.8 C (91.0 F)
1964	36.0 C (96.8 F)
1965	34.7 C (94.5 F)
1966	32.8 C (91.0 F)
1967	33.5 C (92.3 F)
1968	35.4 C (95.7 F)
1969	32.8 C (91.0 F)
1970	33.0 C (91.4 F)
1971	35.0 C (95.0 F)
1972	32.4 C (90.3 F)
1973	32.6 C (90.7 F)
1974	35.1 C (95.2 F)
1975	34.0 C (93.2 F)
1976	32.7 C (90.9 F)
1977	30.0 C (86.0 F)
1978	29.9 C (85.8 F)
1979	30.5 C (86.9 F)
1980	30.5 C (86.9 F)
1981	31.9 C (89.4 F)
1982	30.7 C (87.3 F)
1983	36.6 C (97.9 F)
1984	34.2 C (93.6 F)
1985	32.8 C (91.0 F)
1986	34.6 C (94.3 F)
1987	32.0 C (89.6 F)
1988	33.7 C (92.7 F)
1989	34.1 C (93.4 F)
1990	33.7 C (92.7 F)
1991	32.6 C (90.7 F)
1992	34.4 C (93.9 F)
1993	33.1 C (91.6 F)
1994	32.8 C (91.0 F)
1995	33.5 C (92.3 F)
1996	32.3 C (90.1 F)
1997	31.2 C (88.2 F)
1998	34.4 C (93.9 F)
1999	31.5 C (88.7 F)
2000	34.2 C (93.6 F)
2001	32.4 C (90.3 F)
2002	33.7 C (92.7 F)
2003	37.2 C (99.0 F)
2004	34.8 C (94.6 F)
2005	35.2 C (95.4 F)
2006	35.9 C (96.6 F)
2007	34.2 C (93.6 F)
2008	32.7 C (90.9 F)
2009	35.5 C (95.9 F)
2010	35.6 C (96.1 F)
2011	36.8 C (98.2 F)
2012	36.9 C (98.4 F)
2013	37.2 C (99.0 F)
2014	36.2 C (97.2 F)
2015	37.8 C (100.0 F)
2016	34.8 C (94.6 F)
2017	36.9 C (98.4 F)
2018	36.2 C (97.2 F)
2019	38.0 C (100.4 F)
2020	36.0 C (96.8 F)
2021	33.3 C (91.9 F)
2022	36.8 C (98.2 F)
2023	37.6 C (99.7 F)
2024	34.7 C (94.5 F)
2025	36.1 C (97.0 F)
2026	37.5 C (99.5 F)

Coldest night (TNn)

The coldest night of the year at Sion 2, 1901 to 2026. The record is -20.6 C (-5.1 F) in 1979, marked on the chart; the median year is -11.5 C (11.2 F).

Coldest night (TNn) at Sion 2 by year
Year	Coldest night (TNn)
1901	n/a
1902	n/a
1903	n/a
1904	n/a
1905	n/a
1906	n/a
1907	n/a
1908	n/a
1909	n/a
1910	n/a
1911	n/a
1912	n/a
1913	n/a
1914	n/a
1915	n/a
1916	n/a
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	n/a
1934	n/a
1935	n/a
1936	n/a
1937	n/a
1938	n/a
1939	n/a
1940	n/a
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	-12.2 C (10.0 F)
1956	-17.2 C (1.0 F)
1957	-17.2 C (1.0 F)
1958	-13.9 C (7.0 F)
1959	-11.1 C (12.0 F)
1960	-13.9 C (7.0 F)
1961	-12.2 C (10.0 F)
1962	-17.8 C (0.0 F)
1963	-17.8 C (0.0 F)
1964	-8.8 C (16.2 F)
1965	-10.0 C (14.0 F)
1966	-17.0 C (1.4 F)
1967	-11.0 C (12.2 F)
1968	-14.7 C (5.5 F)
1969	-12.5 C (9.5 F)
1970	-10.7 C (12.7 F)
1971	-14.5 C (5.9 F)
1972	-6.8 C (19.8 F)
1973	-15.5 C (4.1 F)
1974	-8.3 C (17.1 F)
1975	-7.3 C (18.9 F)
1976	-11.5 C (11.3 F)
1977	-8.0 C (17.6 F)
1978	-14.6 C (5.7 F)
1979	-20.6 C (-5.1 F)
1980	-14.2 C (6.4 F)
1981	-15.0 C (5.0 F)
1982	-9.1 C (15.6 F)
1983	-14.6 C (5.7 F)
1984	-10.5 C (13.1 F)
1985	-19.8 C (-3.6 F)
1986	-16.3 C (2.7 F)
1987	-15.1 C (4.8 F)
1988	-9.1 C (15.6 F)
1989	-11.6 C (11.1 F)
1990	-12.0 C (10.4 F)
1991	-13.3 C (8.1 F)
1992	-8.6 C (16.5 F)
1993	-11.3 C (11.7 F)
1994	-8.5 C (16.7 F)
1995	-10.0 C (14.0 F)
1996	-7.9 C (17.8 F)
1997	-6.7 C (19.9 F)
1998	-9.5 C (14.9 F)
1999	-15.9 C (3.4 F)
2000	-10.3 C (13.5 F)
2001	-12.2 C (10.0 F)
2002	-11.1 C (12.0 F)
2003	-9.8 C (14.4 F)
2004	-10.3 C (13.5 F)
2005	-16.0 C (3.2 F)
2006	-12.8 C (9.0 F)
2007	-8.4 C (16.9 F)
2008	-9.9 C (14.2 F)
2009	-11.7 C (10.9 F)
2010	-11.8 C (10.8 F)
2011	-9.6 C (14.7 F)
2012	-13.8 C (7.2 F)
2013	-9.3 C (15.3 F)
2014	-11.6 C (11.1 F)
2015	-9.0 C (15.8 F)
2016	-7.6 C (18.3 F)
2017	-12.1 C (10.2 F)
2018	-9.6 C (14.7 F)
2019	-6.3 C (20.7 F)
2020	-6.3 C (20.7 F)
2021	-11.9 C (10.6 F)
2022	-9.1 C (15.6 F)
2023	-13.0 C (8.6 F)
2024	-7.6 C (18.3 F)
2025	-8.3 C (17.1 F)
2026	-11.9 C (10.6 F)

Wettest day (Rx1day)

The wettest day of the year at Sion 2, 1901 to 2026. The record is 81.3 mm (3.2 in) in 1971, marked on the chart; the median year is 35.6 mm (1.4 in).

Wettest day (Rx1day) at Sion 2 by year
Year	Wettest day (Rx1day)
1901	30.6 mm (1.2 in)
1902	42.3 mm (1.7 in)
1903	27.4 mm (1.1 in)
1904	41.6 mm (1.6 in)
1905	31.0 mm (1.2 in)
1906	26.7 mm (1.1 in)
1907	35.0 mm (1.4 in)
1908	42.3 mm (1.7 in)
1909	33.0 mm (1.3 in)
1910	64.5 mm (2.5 in)
1911	35.7 mm (1.4 in)
1912	47.0 mm (1.9 in)
1913	24.9 mm (1.0 in)
1914	43.7 mm (1.7 in)
1915	33.6 mm (1.3 in)
1916	36.6 mm (1.4 in)
1917	28.4 mm (1.1 in)
1918	58.8 mm (2.3 in)
1919	50.3 mm (2.0 in)
1920	28.3 mm (1.1 in)
1921	17.8 mm (0.7 in)
1922	61.2 mm (2.4 in)
1923	42.5 mm (1.7 in)
1924	32.0 mm (1.3 in)
1925	38.3 mm (1.5 in)
1926	31.7 mm (1.2 in)
1927	30.0 mm (1.2 in)
1928	36.2 mm (1.4 in)
1929	34.5 mm (1.4 in)
1930	32.9 mm (1.3 in)
1931	24.8 mm (1.0 in)
1932	36.4 mm (1.4 in)
1933	29.0 mm (1.1 in)
1934	32.8 mm (1.3 in)
1935	35.3 mm (1.4 in)
1936	26.5 mm (1.0 in)
1937	35.4 mm (1.4 in)
1938	24.0 mm (0.9 in)
1939	36.7 mm (1.4 in)
1940	47.5 mm (1.9 in)
1941	19.4 mm (0.8 in)
1942	26.4 mm (1.0 in)
1943	34.2 mm (1.3 in)
1944	55.3 mm (2.2 in)
1945	39.0 mm (1.5 in)
1946	47.5 mm (1.9 in)
1947	29.4 mm (1.2 in)
1948	51.8 mm (2.0 in)
1949	35.0 mm (1.4 in)
1950	42.2 mm (1.7 in)
1951	29.1 mm (1.1 in)
1952	45.7 mm (1.8 in)
1953	24.3 mm (1.0 in)
1954	65.6 mm (2.6 in)
1955	56.5 mm (2.2 in)
1956	30.4 mm (1.2 in)
1957	68.2 mm (2.7 in)
1958	31.9 mm (1.3 in)
1959	32.0 mm (1.3 in)
1960	42.2 mm (1.7 in)
1961	28.9 mm (1.1 in)
1962	40.5 mm (1.6 in)
1963	46.5 mm (1.8 in)
1964	25.8 mm (1.0 in)
1965	34.3 mm (1.4 in)
1966	50.7 mm (2.0 in)
1967	40.0 mm (1.6 in)
1968	60.5 mm (2.4 in)
1969	43.0 mm (1.7 in)
1970	50.4 mm (2.0 in)
1971	81.3 mm (3.2 in)
1972	33.8 mm (1.3 in)
1973	39.0 mm (1.5 in)
1974	34.7 mm (1.4 in)
1975	27.2 mm (1.1 in)
1976	45.9 mm (1.8 in)
1977	41.7 mm (1.6 in)
1978	50.6 mm (2.0 in)
1979	36.8 mm (1.4 in)
1980	46.1 mm (1.8 in)
1981	28.2 mm (1.1 in)
1982	31.9 mm (1.3 in)
1983	48.5 mm (1.9 in)
1984	29.7 mm (1.2 in)
1985	48.0 mm (1.9 in)
1986	42.3 mm (1.7 in)
1987	27.9 mm (1.1 in)
1988	40.9 mm (1.6 in)
1989	26.9 mm (1.1 in)
1990	79.3 mm (3.1 in)
1991	47.0 mm (1.9 in)
1992	47.5 mm (1.9 in)
1993	32.8 mm (1.3 in)
1994	26.2 mm (1.0 in)
1995	33.2 mm (1.3 in)
1996	45.1 mm (1.8 in)
1997	40.4 mm (1.6 in)
1998	30.8 mm (1.2 in)
1999	32.5 mm (1.3 in)
2000	45.1 mm (1.8 in)
2001	39.1 mm (1.5 in)
2002	44.5 mm (1.8 in)
2003	29.4 mm (1.2 in)
2004	38.1 mm (1.5 in)
2005	33.2 mm (1.3 in)
2006	31.2 mm (1.2 in)
2007	41.1 mm (1.6 in)
2008	22.0 mm (0.9 in)
2009	28.5 mm (1.1 in)
2010	30.3 mm (1.2 in)
2011	46.4 mm (1.8 in)
2012	30.6 mm (1.2 in)
2013	34.8 mm (1.4 in)
2014	30.4 mm (1.2 in)
2015	49.0 mm (1.9 in)
2016	26.3 mm (1.0 in)
2017	46.2 mm (1.8 in)
2018	57.9 mm (2.3 in)
2019	37.4 mm (1.5 in)
2020	31.9 mm (1.3 in)
2021	32.5 mm (1.3 in)
2022	43.7 mm (1.7 in)
2023	34.8 mm (1.4 in)
2024	36.5 mm (1.4 in)
2025	72.8 mm (2.9 in)
2026	20.9 mm (0.8 in)

Wettest five days (Rx5day)

The wettest five days of the year at Sion 2, 1901 to 2026. The record is 196.3 mm (7.7 in) in 1990, marked on the chart; the median year is 63.6 mm (2.5 in).

Wettest five days (Rx5day) at Sion 2 by year
Year	Wettest five days (Rx5day)
1901	51.6 mm (2.0 in)
1902	62.3 mm (2.5 in)
1903	55.2 mm (2.2 in)
1904	67.4 mm (2.7 in)
1905	52.0 mm (2.0 in)
1906	43.4 mm (1.7 in)
1907	52.0 mm (2.0 in)
1908	53.9 mm (2.1 in)
1909	69.6 mm (2.7 in)
1910	128.2 mm (5.0 in)
1911	47.2 mm (1.9 in)
1912	74.9 mm (2.9 in)
1913	35.2 mm (1.4 in)
1914	69.9 mm (2.8 in)
1915	55.5 mm (2.2 in)
1916	78.8 mm (3.1 in)
1917	78.1 mm (3.1 in)
1918	117.3 mm (4.6 in)
1919	62.8 mm (2.5 in)
1920	47.8 mm (1.9 in)
1921	33.6 mm (1.3 in)
1922	89.1 mm (3.5 in)
1923	98.8 mm (3.9 in)
1924	60.9 mm (2.4 in)
1925	88.7 mm (3.5 in)
1926	59.5 mm (2.3 in)
1927	41.9 mm (1.6 in)
1928	81.2 mm (3.2 in)
1929	47.5 mm (1.9 in)
1930	77.0 mm (3.0 in)
1931	51.5 mm (2.0 in)
1932	55.8 mm (2.2 in)
1933	40.4 mm (1.6 in)
1934	58.5 mm (2.3 in)
1935	68.3 mm (2.7 in)
1936	49.7 mm (2.0 in)
1937	59.1 mm (2.3 in)
1938	46.8 mm (1.8 in)
1939	62.0 mm (2.4 in)
1940	78.6 mm (3.1 in)
1941	30.1 mm (1.2 in)
1942	49.7 mm (2.0 in)
1943	52.9 mm (2.1 in)
1944	106.6 mm (4.2 in)
1945	59.4 mm (2.3 in)
1946	63.9 mm (2.5 in)
1947	59.5 mm (2.3 in)
1948	71.8 mm (2.8 in)
1949	45.2 mm (1.8 in)
1950	80.9 mm (3.2 in)
1951	60.6 mm (2.4 in)
1952	72.0 mm (2.8 in)
1953	38.5 mm (1.5 in)
1954	90.2 mm (3.6 in)
1955	135.0 mm (5.3 in)
1956	52.0 mm (2.0 in)
1957	118.5 mm (4.7 in)
1958	56.5 mm (2.2 in)
1959	74.3 mm (2.9 in)
1960	62.6 mm (2.5 in)
1961	85.0 mm (3.3 in)
1962	73.8 mm (2.9 in)
1963	63.6 mm (2.5 in)
1964	68.2 mm (2.7 in)
1965	67.2 mm (2.6 in)
1966	70.4 mm (2.8 in)
1967	84.4 mm (3.3 in)
1968	79.9 mm (3.1 in)
1969	61.9 mm (2.4 in)
1970	110.6 mm (4.4 in)
1971	100.2 mm (3.9 in)
1972	91.7 mm (3.6 in)
1973	65.5 mm (2.6 in)
1974	81.2 mm (3.2 in)
1975	59.1 mm (2.3 in)
1976	85.8 mm (3.4 in)
1977	76.3 mm (3.0 in)
1978	81.2 mm (3.2 in)
1979	62.1 mm (2.4 in)
1980	73.0 mm (2.9 in)
1981	75.9 mm (3.0 in)
1982	50.5 mm (2.0 in)
1983	84.6 mm (3.3 in)
1984	56.7 mm (2.2 in)
1985	79.4 mm (3.1 in)
1986	50.1 mm (2.0 in)
1987	49.5 mm (1.9 in)
1988	79.8 mm (3.1 in)
1989	50.4 mm (2.0 in)
1990	196.3 mm (7.7 in)
1991	80.6 mm (3.2 in)
1992	97.3 mm (3.8 in)
1993	65.3 mm (2.6 in)
1994	58.9 mm (2.3 in)
1995	67.2 mm (2.6 in)
1996	79.4 mm (3.1 in)
1997	57.7 mm (2.3 in)
1998	50.0 mm (2.0 in)
1999	65.9 mm (2.6 in)
2000	96.1 mm (3.8 in)
2001	74.5 mm (2.9 in)
2002	58.4 mm (2.3 in)
2003	47.1 mm (1.9 in)
2004	71.9 mm (2.8 in)
2005	39.2 mm (1.5 in)
2006	56.9 mm (2.2 in)
2007	69.2 mm (2.7 in)
2008	37.5 mm (1.5 in)
2009	48.2 mm (1.9 in)
2010	55.7 mm (2.2 in)
2011	92.9 mm (3.7 in)
2012	63.6 mm (2.5 in)
2013	51.0 mm (2.0 in)
2014	41.4 mm (1.6 in)
2015	96.9 mm (3.8 in)
2016	81.2 mm (3.2 in)
2017	65.8 mm (2.6 in)
2018	106.6 mm (4.2 in)
2019	54.9 mm (2.2 in)
2020	59.1 mm (2.3 in)
2021	62.9 mm (2.5 in)
2022	62.5 mm (2.5 in)
2023	81.0 mm (3.2 in)
2024	59.9 mm (2.4 in)
2025	84.9 mm (3.3 in)
2026	62.0 mm (2.4 in)

Longest dry spell (CDD)

The longest dry spell of the year at Sion 2, 1901 to 2026. The record is 64 days in 1920, marked on the chart; the median year is 27 days.

Longest dry spell (CDD) at Sion 2 by year
Year	Longest dry spell (CDD)
1901	21 days
1902	22 days
1903	26 days
1904	17 days
1905	33 days
1906	25 days
1907	25 days
1908	28 days
1909	29 days
1910	34 days
1911	23 days
1912	21 days
1913	24 days
1914	36 days
1915	23 days
1916	31 days
1917	27 days
1918	42 days
1919	33 days
1920	64 days
1921	51 days
1922	20 days
1923	22 days
1924	30 days
1925	33 days
1926	22 days
1927	26 days
1928	42 days
1929	25 days
1930	22 days
1931	27 days
1932	58 days
1933	23 days
1934	32 days
1935	20 days
1936	31 days
1937	17 days
1938	36 days
1939	30 days
1940	21 days
1941	26 days
1942	28 days
1943	47 days
1944	21 days
1945	23 days
1946	37 days
1947	36 days
1948	32 days
1949	24 days
1950	22 days
1951	22 days
1952	21 days
1953	55 days
1954	24 days
1955	28 days
1956	32 days
1957	32 days
1958	27 days
1959	41 days
1960	27 days
1961	30 days
1962	21 days
1963	36 days
1964	29 days
1965	36 days
1966	20 days
1967	22 days
1968	21 days
1969	23 days
1970	24 days
1971	29 days
1972	33 days
1973	23 days
1974	23 days
1975	31 days
1976	24 days
1977	15 days
1978	51 days
1979	23 days
1980	31 days
1981	27 days
1982	20 days
1983	39 days
1984	24 days
1985	46 days
1986	28 days
1987	29 days
1988	23 days
1989	37 days
1990	24 days
1991	29 days
1992	26 days
1993	25 days
1994	23 days
1995	31 days
1996	35 days
1997	36 days
1998	33 days
1999	19 days
2000	28 days
2001	21 days
2002	22 days
2003	29 days
2004	30 days
2005	29 days
2006	27 days
2007	35 days
2008	28 days
2009	23 days
2010	26 days
2011	43 days
2012	32 days
2013	25 days
2014	26 days
2015	22 days
2016	42 days
2017	33 days
2018	31 days
2019	32 days
2020	44 days
2021	25 days
2022	23 days
2023	49 days
2024	19 days
2025	34 days
2026	20 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

66 years with a frost

Across 66 years with a frost, the median last spring frost at Sion 2 falls on 11 April and the median first autumn frost on 31 October, which leaves a median of 205 days between them.

In 1994 to 2025 the median growing season was 215 days. That is 27 days more than in 1955 to 1987.

Fitted over all years, the growing season changes by +6.5 days per decade at this station.

Frost dates and growing season at Sion 2
Measure	Median, all years	Earliest period (1955 to 1987)	Recent period (1994 to 2025)	Recent against earliest	Fitted trend
Last spring frost	11 April	23 April	5 April	18 days earlier	-4.2 days per decade
First autumn frost	31 October	26 October	5 November	10 days later	+2.3 days per decade
Growing days	205 days	188 days	215 days	27 days more	+6.5 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

125 years, 1901 to 2025

A day with at least 36.4 mm (1.4 in) of rain is expected about once in 2 years. A day with at least 78.9 mm (3.1 in) of rain is expected about once in 100 years.

Rainfall return levels at Sion 2: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	36.4 mm (1.4 in)
5 years	46.6 mm (1.8 in)
10 years	53.8 mm (2.1 in)
25 years	63.5 mm (2.5 in)
50 years	71.0 mm (2.8 in)
100 years	78.9 mm (3.1 in)

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 125 years of values from 1901 to 2025.

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: 81.3 mm (3.2 in) in 1971; 79.3 mm (3.1 in) in 1990; 72.8 mm (2.9 in) in 2025.

Station Changes

2 suspected

2 changes were suspected in the annual mean temperature of Sion 2, at 1977 and 1986. Each is measured against neighbouring stations.

Relative to 5 neighbouring stations, the station's annual mean temperature from 1977 ran 1.0 C (1.8 F) lower than in the years before (likely change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1986 ran 0.6 C (1.1 F) higher than in the years before (likely change).

Suspected changes in the annual mean temperature at Sion 2, against neighbouring stations
Year	Shift (C)	Shift (F)	Strength	Neighbours
1977	-1.0	-1.8	likely	5
1986	+0.6	+1.1	likely	5

Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.

Climate Twins

2009 to 2025 against 1961 to 1990

Over 2009 to 2025, Sion 2 had a mean temperature of 11.7 C (53.0 F) and 594.2 mm (23.4 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Nis (Serbia, 1,192 km away), Budapest (Hungary, 899 km away) and Belgrade (Observatory) (Serbia, 1,034 km away).

Climate twins of Sion 2: stations whose 1961 to 1990 climate is closest to its 2009 to 2025 climate
Twin station	Country	Distance away	Mean temperature, 1961-1990	Rain a year, 1961-1990	Climate difference
Nis	Serbia	1,192 km (741 mi)	11.7 C (53.1 F)	589.6 mm (23.2 in)	0.72
Budapest	Hungary	899 km (559 mi)	11.5 C (52.7 F)	562.9 mm (22.2 in)	0.80
Belgrade (Observatory)	Serbia	1,034 km (642 mi)	12.2 C (54.0 F)	684.4 mm (26.9 in)	0.99

Twins are stations, not cities. A twin is one of the three stations at least 100 km away whose earlier climate is closest to this station's recent one, so a close match does not mean the two places look alike in other ways. A station move or a gap in a record can change that station's averages. The list describes past climate; it is not a forecast and does not say what caused any change. How twins are found, and a search for any station.

Download the Data

Data for Sion 2 standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Sion 2 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 2026-10-13 (13 October 2026). Records are computed by this site and are not official.

Data as of 2026-10-13. Last revised 13 October 2026 (2026-10-13).