Built 2026-10-19 (19 October 2026)

Wiarton A Weather Records (CA006119500)

Record envelope, standing records and threshold days for Wiarton A (CA006119500), Ontario, Canada, with 68 years of record.

Key Facts for Wiarton A

  • Wiarton A (CA006119500) is a weather station in Ontario, Canada at 44.75 latitude and -81.10 longitude, 222 m (728 ft) above sea level.
  • The station reports from 1947 to 2014, 68 years of record.
  • 1,464 records set at Wiarton A still stand.
  • Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
  • Wiarton A set a daily record snowfall of 15.4 cm (6.1 in) on 26 December 1983.

About the Station

  • Location: Ontario, Canada, 44.75 latitude, -81.10 longitude.
  • Elevation: 222 m (728 ft).
  • Period of record: 1947 to 2014, 68 years.
  • Eligible elements: tmax, tmin, prcp, snow.

Daily Record Envelope and 2026

0 days at or beyond a record
Daily record high and record low at Wiarton A, with 2026 drawn through them The band shows the record high and record low for each calendar day at Wiarton A. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -40-2002040 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Wiarton A. 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 Wiarton A, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan17.8 C (64.0 F)-36.4 C (-33.5 F)n/an/a
Feb11.7 C (53.1 F)-34.8 C (-30.6 F)n/an/a
Mar20.9 C (69.6 F)-30.7 C (-23.3 F)n/an/a
Apr27.8 C (82.0 F)-16.7 C (1.9 F)n/an/a
May30.5 C (86.9 F)-5.0 C (23.0 F)n/an/a
Jun33.3 C (91.9 F)-1.6 C (29.1 F)n/an/a
Jul33.3 C (91.9 F)3.3 C (37.9 F)n/an/a
Aug35.0 C (95.0 F)1.7 C (35.1 F)n/an/a
Sep35.6 C (96.1 F)-2.8 C (27.0 F)n/an/a
Oct28.3 C (82.9 F)-7.2 C (19.0 F)n/an/a
Nov23.3 C (73.9 F)-15.0 C (5.0 F)n/an/a
Dec17.8 C (64.0 F)-26.6 C (-15.9 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Wiarton A by the year they were set 1,464 records at Wiarton A still stand. 1965 holds the most, with 62. 0204060801947: 391948: 331949: 601950: 531951: 411952: 251953: 431954: 351955: 441956: 421957: 481958: 361959: 501960: 261961: 291962: 321963: 461964: 541965: 621966: 411967: 361968: 441969: 221970: 231971: 241972: 241973: 371974: 401975: 341976: 501977: 521978: 401979: 441980: 371981: 401982: 371983: 411947195119551959196319671971197519791983
1,464 records at Wiarton A still stand. 1965 holds the most, with 62.
Standing records at Wiarton A by the year they were set
Year setStanding records
194739
194833
194960
195053
195141
195225
195343
195435
195544
195642
195748
195836
195950
196026
196129
196232
196346
196454
196562
196641
196736
196844
196922
197023
197124
197224
197337
197440
197534
197650
197752
197840
197944
198037
198140
198237
198341

All-Time Record Progression

1 new records
When Wiarton A set new all-time records 1 all-time records were set at Wiarton A between 31 January 1982 and 31 January 1982. Each dot is a new record. Record daily snowfall31 January 1982: Record daily snowfall 51.4 cm (20.2 in)
1 all-time records were set at Wiarton A between 31 January 1982 and 31 January 1982. Each dot is a new record.
When Wiarton A set new all-time records
DateKindDetail
1982-01-31Record daily snowfallRecord daily snowfall 51.4 cm (20.2 in)

Wettest Day of Each Month

Jul: 104.6 mm (4.1 in)
Record daily precipitation for each month at Wiarton A The wettest day on record for each calendar month at Wiarton A. The most was 104.6 mm (4.1 in) on 28 July 1969. 050100150 Jan: 47.6 mm (1.9 in), 31 January 1982 Jan Feb: 33.5 mm (1.3 in), 22 February 1974 Feb Mar: 47.2 mm (1.9 in), 17 March 1973 Mar Apr: 39.1 mm (1.5 in), 12 April 1951 Apr May: 44.0 mm (1.7 in), 7 May 1983 May Jun: 67.8 mm (2.7 in), 23 June 1950 Jun Jul: 104.6 mm (4.1 in), 28 July 1969 Jul Aug: 73.4 mm (2.9 in), 20 August 1968 Aug Sep: 88.6 mm (3.5 in), 12 September 1963 Sep Oct: 69.3 mm (2.7 in), 15 October 1954 Oct Nov: 36.1 mm (1.4 in), 13 November 1959 Nov Dec: 45.5 mm (1.8 in), 6 December 1962 Dec
The wettest day on record for each calendar month at Wiarton A. The most was 104.6 mm (4.1 in) on 28 July 1969.
Record daily precipitation for each month at Wiarton A
MonthRecord daily precipitation (mm)Date
Jan47.6 mm (1.9 in)31 January 1982
Feb33.5 mm (1.3 in)22 February 1974
Mar47.2 mm (1.9 in)17 March 1973
Apr39.1 mm (1.5 in)12 April 1951
May44.0 mm (1.7 in)7 May 1983
Jun67.8 mm (2.7 in)23 June 1950
Jul104.6 mm (4.1 in)28 July 1969
Aug73.4 mm (2.9 in)20 August 1968
Sep88.6 mm (3.5 in)12 September 1963
Oct69.3 mm (2.7 in)15 October 1954
Nov36.1 mm (1.4 in)13 November 1959
Dec45.5 mm (1.8 in)6 December 1962

Period of Record Coverage

1947 to 1983
Days with data per year at Wiarton A 37 years of record at Wiarton A, 1947 to 1983. 2 years have data for under 90 percent of days and are left out of rankings: 1947, 1979. 1947: 181 of 365 days1948: 366 of 366 days1949: 365 of 365 days1950: 365 of 365 days1951: 365 of 365 days1952: 366 of 366 days1953: 335 of 365 days1954: 365 of 365 days1955: 365 of 365 days1956: 366 of 366 days1957: 365 of 365 days1958: 365 of 365 days1959: 365 of 365 days1960: 366 of 366 days1961: 365 of 365 days1962: 365 of 365 days1963: 365 of 365 days1964: 366 of 366 days1965: 365 of 365 days1966: 365 of 365 days1967: 365 of 365 days1968: 366 of 366 days1969: 365 of 365 days1970: 365 of 365 days1971: 365 of 365 days1972: 366 of 366 days1973: 365 of 365 days1974: 365 of 365 days1975: 365 of 365 days1976: 366 of 366 days1977: 365 of 365 days1978: 365 of 365 days1979: 304 of 365 days1980: 366 of 366 days1981: 365 of 365 days1982: 364 of 365 days1983: 365 of 365 days1950195519601965197019751980
37 years of record at Wiarton A, 1947 to 1983. 2 years have data for under 90 percent of days and are left out of rankings: 1947, 1979.
Days with data per year at Wiarton A
YearDays with dataShare of yearComplete
194718150%No
1948366100%Yes
1949365100%Yes
1950365100%Yes
1951365100%Yes
1952366100%Yes
195333592%Yes
1954365100%Yes
1955365100%Yes
1956366100%Yes
1957365100%Yes
1958365100%Yes
1959365100%Yes
1960366100%Yes
1961365100%Yes
1962365100%Yes
1963365100%Yes
1964366100%Yes
1965365100%Yes
1966365100%Yes
1967365100%Yes
1968366100%Yes
1969365100%Yes
1970365100%Yes
1971365100%Yes
1972366100%Yes
1973365100%Yes
1974365100%Yes
1975365100%Yes
1976366100%Yes
1977365100%Yes
1978365100%Yes
197930483%No
1980366100%Yes
1981365100%Yes
1982364100%Yes
1983365100%Yes

Latest Records

20
Latest records at Wiarton A
DateStationRecordValueBeat old record byOld record stoodSignificance
26 December 1983Wiarton A, CAdaily snowfall15.4 cm (6.1 in)4.2 cm (1.7 in)20 years17 of 100 (Routine)
21 December 1983Wiarton A, CAdaily low min-23.4 C (-10.1 F)2.3 C (4.1 F)8 years8 of 100 (Routine)
20 December 1983Wiarton A, CAdaily low min-21.8 C (-7.2 F)3.5 C (6.3 F)24 years15 of 100 (Routine)
19 December 1983Wiarton A, CAdaily low max-10.1 C (13.8 F)1.2 C (2.2 F)28 years13 of 100 (Routine)
9 December 1983Wiarton A, CAdaily snowfall19.2 cm (7.6 in)3.8 cm (1.5 in)5 years11 of 100 (Routine)
16 November 1983Wiarton A, CAdaily snowfall11.1 cm (4.4 in)6.0 cm (2.4 in)36 years26 of 100 (Routine)
16 November 1983Wiarton A, CAdaily rain29.4 mm (1.2 in)7.6 mm (0.30 in)5 years18 of 100 (Routine)
12 November 1983Wiarton A, CAdaily low max-2.0 C (28.4 F)0.7 C (1.3 F)5 years5 of 100 (Routine)
12 November 1983Wiarton A, CAdaily low min-7.8 C (18.0 F)1.3 C (2.3 F)1 year5 of 100 (Routine)
11 November 1983Wiarton A, CAdaily snowfall20.9 cm (8.2 in)12.5 cm (4.9 in)32 years39 of 100 (Notable)
11 November 1983Wiarton A, CAdaily rain21.3 mm (0.8 in)6.8 mm (0.27 in)16 years19 of 100 (Routine)
20 October 1983Wiarton A, CAdaily low min-3.9 C (25.0 F)1.1 C (2.0 F)30 years14 of 100 (Routine)
14 October 1983Wiarton A, CAdaily snowfall0.3 cm (0.1 in)0.3 cm (0.1 in)36 years14 of 100 (Routine)
12 October 1983Wiarton A, CAdaily high min14.1 C (57.4 F)0.8 C (1.4 F)28 years12 of 100 (Routine)
3 October 1983Wiarton A, CAdaily high min16.5 C (61.7 F)0.9 C (1.6 F)12 years7 of 100 (Routine)
3 October 1983Wiarton A, CAdaily rain24.9 mm (1.0 in)2.6 mm (0.10 in)2 years6 of 100 (Routine)
20 September 1983Wiarton A, CAdaily high max28.0 C (82.4 F)0.8 C (1.4 F)17 years9 of 100 (Routine)
16 September 1983Wiarton A, CAdaily rain20.8 mm (0.8 in)6.1 mm (0.24 in)13 years13 of 100 (Routine)
10 September 1983Wiarton A, CAdaily high max (Tie)31.1 C (88.0 F)tie36 years3 of 100 (Routine)
5 September 1983Wiarton A, CAdaily high max31.9 C (89.4 F)1.3 C (2.3 F)34 years15 of 100 (Routine)

Climate Trend

34 complete years, 1948 to 1983
Annual mean temperature at Wiarton A as warming stripes, 1948 to 1983 One stripe for each of 34 complete years at Wiarton A, 1948 to 1983. Blue stripes are years cooler than the station's own mean of 6.0 C (42.9 F); red stripes are warmer. The coolest year was 1978, at 4.8 C (40.7 F), and the warmest was 1949, at 7.3 C (45.1 F). The strongest colour marks a difference of 1.3 C (2.3 F). 1948: 6.6 C, +0.6 C from the station mean1949: 7.3 C, +1.2 C from the station mean1950: 5.8 C, -0.2 C from the station mean1951: 6.3 C, +0.3 C from the station mean1952: 7.1 C, +1.0 C from the station mean1954: 6.2 C, +0.1 C from the station mean1955: 7.1 C, +1.1 C from the station mean1956: 5.8 C, -0.2 C from the station mean1957: 6.5 C, +0.5 C from the station mean1958: 5.8 C, -0.2 C from the station mean1959: 6.5 C, +0.4 C from the station mean1960: 5.9 C, -0.1 C from the station mean1961: 6.4 C, +0.4 C from the station mean1962: 5.7 C, -0.3 C from the station mean1963: 5.3 C, -0.7 C from the station mean1964: 6.8 C, +0.8 C from the station mean1965: 5.5 C, -0.5 C from the station mean1966: 5.9 C, -0.1 C from the station mean1967: 5.7 C, -0.4 C from the station mean1968: 6.1 C, +0.1 C from the station mean1969: 5.8 C, -0.3 C from the station mean1970: 5.9 C, -0.1 C from the station mean1971: 6.3 C, +0.2 C from the station mean1972: 4.9 C, -1.1 C from the station mean1973: 6.9 C, +0.9 C from the station mean1974: 5.7 C, -0.3 C from the station mean1975: 6.6 C, +0.5 C from the station mean1976: 5.1 C, -1.0 C from the station mean1977: 5.5 C, -0.5 C from the station mean1978: 4.8 C, -1.2 C from the station mean1980: 5.1 C, -0.9 C from the station mean1981: 5.9 C, -0.1 C from the station mean1982: 5.8 C, -0.2 C from the station mean1983: 6.7 C, +0.6 C from the station mean1948195519601965197019751980
One stripe for each of 34 complete years at Wiarton A, 1948 to 1983. Blue stripes are years cooler than the station's own mean of 6.0 C (42.9 F); red stripes are warmer. The coolest year was 1978, at 4.8 C (40.7 F), and the warmest was 1949, at 7.3 C (45.1 F). The strongest colour marks a difference of 1.3 C (2.3 F).
Annual mean temperature at Wiarton A as warming stripes, 1948 to 1983
YearAnnual mean temperatureDifference from the station mean
19486.6 C+0.55 C
19497.3 C+1.23 C
19505.8 C-0.24 C
19516.3 C+0.27 C
19527.1 C+1.04 C
19546.2 C+0.11 C
19557.1 C+1.08 C
19565.8 C-0.20 C
19576.5 C+0.48 C
19585.8 C-0.24 C
19596.5 C+0.44 C
19605.9 C-0.13 C
19616.4 C+0.36 C
19625.7 C-0.30 C
19635.3 C-0.70 C
19646.8 C+0.76 C
19655.5 C-0.54 C
19665.9 C-0.11 C
19675.7 C-0.37 C
19686.1 C+0.08 C
19695.8 C-0.27 C
19705.9 C-0.10 C
19716.3 C+0.22 C
19724.9 C-1.12 C
19736.9 C+0.90 C
19745.7 C-0.33 C
19756.6 C+0.54 C
19765.1 C-0.97 C
19775.5 C-0.54 C
19784.8 C-1.22 C
19805.1 C-0.95 C
19815.9 C-0.12 C
19825.8 C-0.25 C
19836.7 C+0.63 C

The annual mean temperature here has fallen by 0.3 C (0.1 to 0.5) per decade over 1948 to 1983. In Fahrenheit: 0.5 F (0.1 to 0.8) 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 Wiarton A
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature-0.3 C (-0.5 to -0.1) per decade-0.5 F (-0.8 to -0.1) per decade1948 to 198334Fall
Mean daily maximum-0.1 C (-0.3 to 0.1) per decade-0.2 F (-0.6 to 0.1) per decade1948 to 198334Not clearly different from zero
Mean daily minimum-0.4 C (-0.6 to -0.2) per decade-0.8 F (-1.2 to -0.4) per decade1948 to 198334Fall

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

1947 to 1983
Yearly extremes at Wiarton A: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)35.6 C (96.1 F)195331.7 C (89.1 F)37
Coldest night (TNn)-36.4 C (-33.5 F)1977-25.6 C (-14.1 F)37
Wettest day (Rx1day)104.6 mm (4.1 in)196945.7 mm (1.8 in)37
Wettest five days (Rx5day)155.4 mm (6.1 in)196974.9 mm (2.9 in)37
Longest dry spell (CDD)33 days196617 days37

Hottest day (TXx)

Hottest day (TXx) at Wiarton A by year The hottest day of the year at Wiarton A, 1947 to 1983. The record is 35.6 C (96.1 F) in 1953, marked on the chart; the median year is 31.7 C (89.1 F). 28303234361950196019701980Record: 35.6 C (96.1 F) in 1953
The hottest day of the year at Wiarton A, 1947 to 1983. The record is 35.6 C (96.1 F) in 1953, marked on the chart; the median year is 31.7 C (89.1 F).
Hottest day (TXx) at Wiarton A by year
YearHottest day (TXx)
194735.0 C (95.0 F)
194833.9 C (93.0 F)
194932.2 C (90.0 F)
195030.0 C (86.0 F)
195128.9 C (84.0 F)
195232.8 C (91.0 F)
195335.6 C (96.1 F)
195432.2 C (90.0 F)
195532.2 C (90.0 F)
195628.3 C (82.9 F)
195731.7 C (89.1 F)
195830.6 C (87.1 F)
195932.8 C (91.0 F)
196032.2 C (90.0 F)
196131.7 C (89.1 F)
196232.8 C (91.0 F)
196331.7 C (89.1 F)
196431.7 C (89.1 F)
196533.3 C (91.9 F)
196633.3 C (91.9 F)
196730.0 C (86.0 F)
196833.3 C (91.9 F)
196930.0 C (86.0 F)
197029.4 C (84.9 F)
197131.7 C (89.1 F)
197230.0 C (86.0 F)
197330.6 C (87.1 F)
197431.1 C (88.0 F)
197531.7 C (89.1 F)
197631.7 C (89.1 F)
197730.9 C (87.6 F)
197831.8 C (89.2 F)
197931.6 C (88.9 F)
198029.3 C (84.7 F)
198128.8 C (83.8 F)
198231.9 C (89.4 F)
198331.9 C (89.4 F)

Coldest night (TNn)

Coldest night (TNn) at Wiarton A by year The coldest night of the year at Wiarton A, 1947 to 1983. The record is -36.4 C (-33.5 F) in 1977, marked on the chart; the median year is -25.6 C (-14.1 F). -40-35-30-25-20-151950196019701980Record: -36.4 C (-33.5 F) in 1977
The coldest night of the year at Wiarton A, 1947 to 1983. The record is -36.4 C (-33.5 F) in 1977, marked on the chart; the median year is -25.6 C (-14.1 F).
Coldest night (TNn) at Wiarton A by year
YearColdest night (TNn)
1947-17.8 C (0.0 F)
1948-30.0 C (-22.0 F)
1949-20.0 C (-4.0 F)
1950-22.2 C (-8.0 F)
1951-22.8 C (-9.0 F)
1952-23.3 C (-9.9 F)
1953-18.9 C (-2.0 F)
1954-23.3 C (-9.9 F)
1955-24.4 C (-11.9 F)
1956-22.8 C (-9.0 F)
1957-23.9 C (-11.0 F)
1958-23.3 C (-9.9 F)
1959-27.2 C (-17.0 F)
1960-23.9 C (-11.0 F)
1961-26.1 C (-15.0 F)
1962-32.8 C (-27.0 F)
1963-31.1 C (-24.0 F)
1964-23.3 C (-9.9 F)
1965-26.7 C (-16.1 F)
1966-26.1 C (-15.0 F)
1967-27.2 C (-17.0 F)
1968-25.6 C (-14.1 F)
1969-23.3 C (-9.9 F)
1970-25.0 C (-13.0 F)
1971-26.7 C (-16.1 F)
1972-25.6 C (-14.1 F)
1973-26.1 C (-15.0 F)
1974-27.2 C (-17.0 F)
1975-22.8 C (-9.0 F)
1976-29.4 C (-20.9 F)
1977-36.4 C (-33.5 F)
1978-31.6 C (-24.9 F)
1979-34.8 C (-30.6 F)
1980-30.7 C (-23.3 F)
1981-33.0 C (-27.4 F)
1982-26.5 C (-15.7 F)
1983-23.4 C (-10.1 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Wiarton A by year The wettest day of the year at Wiarton A, 1947 to 1983. The record is 104.6 mm (4.1 in) in 1969, marked on the chart; the median year is 45.7 mm (1.8 in). 204060801001201950196019701980Record: 104.6 mm (4.1 in) in 1969
The wettest day of the year at Wiarton A, 1947 to 1983. The record is 104.6 mm (4.1 in) in 1969, marked on the chart; the median year is 45.7 mm (1.8 in).
Wettest day (Rx1day) at Wiarton A by year
YearWettest day (Rx1day)
194728.4 mm (1.1 in)
194836.1 mm (1.4 in)
194929.7 mm (1.2 in)
195067.8 mm (2.7 in)
195148.0 mm (1.9 in)
195238.9 mm (1.5 in)
195346.0 mm (1.8 in)
195469.3 mm (2.7 in)
195574.9 mm (2.9 in)
195640.4 mm (1.6 in)
195738.9 mm (1.5 in)
195841.7 mm (1.6 in)
195940.4 mm (1.6 in)
196062.2 mm (2.4 in)
196157.9 mm (2.3 in)
196245.5 mm (1.8 in)
196388.6 mm (3.5 in)
196433.5 mm (1.3 in)
196565.5 mm (2.6 in)
196629.5 mm (1.2 in)
196755.1 mm (2.2 in)
196873.4 mm (2.9 in)
1969104.6 mm (4.1 in)
197043.2 mm (1.7 in)
197135.6 mm (1.4 in)
197236.1 mm (1.4 in)
197389.7 mm (3.5 in)
197454.9 mm (2.2 in)
197529.7 mm (1.2 in)
197637.1 mm (1.5 in)
197750.3 mm (2.0 in)
197845.8 mm (1.8 in)
197941.2 mm (1.6 in)
198059.8 mm (2.4 in)
198145.7 mm (1.8 in)
198247.6 mm (1.9 in)
198344.0 mm (1.7 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Wiarton A by year The wettest five days of the year at Wiarton A, 1947 to 1983. The record is 155.4 mm (6.1 in) in 1969, marked on the chart; the median year is 74.9 mm (2.9 in). 0501001502001950196019701980Record: 155.4 mm (6.1 in) in 1969
The wettest five days of the year at Wiarton A, 1947 to 1983. The record is 155.4 mm (6.1 in) in 1969, marked on the chart; the median year is 74.9 mm (2.9 in).
Wettest five days (Rx5day) at Wiarton A by year
YearWettest five days (Rx5day)
194775.0 mm (3.0 in)
194899.6 mm (3.9 in)
194956.2 mm (2.2 in)
195078.0 mm (3.1 in)
195163.7 mm (2.5 in)
195248.1 mm (1.9 in)
195359.5 mm (2.3 in)
1954119.1 mm (4.7 in)
195593.0 mm (3.7 in)
195683.3 mm (3.3 in)
195782.6 mm (3.3 in)
195852.7 mm (2.1 in)
195968.4 mm (2.7 in)
196087.6 mm (3.4 in)
196186.2 mm (3.4 in)
196269.9 mm (2.8 in)
196388.6 mm (3.5 in)
196454.4 mm (2.1 in)
196571.1 mm (2.8 in)
196659.4 mm (2.3 in)
1967118.9 mm (4.7 in)
1968115.1 mm (4.5 in)
1969155.4 mm (6.1 in)
197061.8 mm (2.4 in)
197159.3 mm (2.3 in)
197278.5 mm (3.1 in)
1973114.4 mm (4.5 in)
197469.9 mm (2.8 in)
197551.3 mm (2.0 in)
197675.0 mm (3.0 in)
197772.4 mm (2.9 in)
197887.3 mm (3.4 in)
197965.4 mm (2.6 in)
198074.9 mm (2.9 in)
198167.3 mm (2.6 in)
198263.9 mm (2.5 in)
198392.1 mm (3.6 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Wiarton A by year The longest dry spell of the year at Wiarton A, 1947 to 1983. The record is 33 days in 1966, marked on the chart; the median year is 17 days. 102030401950196019701980Record: 33 days in 1966
The longest dry spell of the year at Wiarton A, 1947 to 1983. The record is 33 days in 1966, marked on the chart; the median year is 17 days.
Longest dry spell (CDD) at Wiarton A by year
YearLongest dry spell (CDD)
194722 days
194828 days
194925 days
195018 days
195117 days
195217 days
195315 days
195431 days
195514 days
195617 days
195715 days
195819 days
195920 days
196012 days
196115 days
196219 days
196323 days
196422 days
196516 days
196633 days
196720 days
196817 days
196917 days
197016 days
197110 days
197213 days
197316 days
197412 days
197520 days
197612 days
197721 days
197816 days
197922 days
198013 days
198125 days
198214 days
198319 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

34 years with a frost

Across 34 years with a frost, the median last spring frost at Wiarton A falls on 15 May and the median first autumn frost on 6 October, which leaves a median of 140 days between them.

Fitted over all years, the growing season changes by +0.9 days per decade at this station.

Frost dates and growing season at Wiarton A
MeasureMedian, all yearsEarliest periodRecent period (1952 to 1983)Recent against earliestFitted trend
Last spring frost15 Mayn/a17 Mayn/a-1.7 days per decade
First autumn frost6 Octobern/a5 Octobern/a-0.8 days per decade
Growing days140 daysn/a140 daysn/a+0.9 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

35 years, 1948 to 1983

A day with at least 47.1 mm (1.9 in) of rain is expected about once in 2 years. A day with at least 122.8 mm (4.8 in) of rain is expected about once in 100 years.

Rainfall return levels at Wiarton A: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years47.1 mm (1.9 in)
5 years63.2 mm (2.5 in)
10 years75.3 mm (3.0 in)
25 years92.6 mm (3.6 in)
50 years107.0 mm (4.2 in)Longer than the 35 years of record
100 years122.8 mm (4.8 in)Longer than the 35 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, 35 years of values from 1948 to 1983.

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: 104.6 mm (4.1 in) in 1969; 89.7 mm (3.5 in) in 1973; 88.6 mm (3.5 in) in 1963.

Download the Data

  • Data for Wiarton A standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Wiarton A 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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.

Data as of . Last revised (2026-10-17).