Built 2026-10-15 (15 October 2026)

Irwin Weather Records (USC00364276)

Record envelope, standing records and threshold days for Irwin (USC00364276), Pennsylvania, United States, with 63 years of record.

Key Facts for Irwin

  • Irwin (USC00364276) is a weather station in Pennsylvania, United States at 40.33 latitude and -79.70 longitude, 336 m (1,102 ft) above sea level.
  • The station reports from 1896 to 1958, 63 years of record.
  • 1,464 records set at Irwin still stand.
  • Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
  • Irwin set a daily record snowfall of 17.8 cm (7.0 in) on 14 March 1958.

About the Station

  • Location: Pennsylvania, United States, 40.33 latitude, -79.70 longitude.
  • Elevation: 336 m (1,102 ft).
  • Period of record: 1896 to 1958, 63 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 Irwin, with 2026 drawn through them The band shows the record high and record low for each calendar day at Irwin. 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 Irwin. 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 Irwin, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan27.2 C (81.0 F)-30.0 C (-22.0 F)n/an/a
Feb24.4 C (75.9 F)-27.2 C (-17.0 F)n/an/a
Mar30.0 C (86.0 F)-21.1 C (-6.0 F)n/an/a
Apr33.3 C (91.9 F)-18.3 C (-0.9 F)n/an/a
May37.2 C (99.0 F)-6.1 C (21.0 F)n/an/a
Jun36.7 C (98.1 F)0.6 C (33.1 F)n/an/a
Jul40.0 C (104.0 F)3.3 C (37.9 F)n/an/a
Aug39.4 C (102.9 F)0.0 C (32.0 F)n/an/a
Sep38.9 C (102.0 F)-4.4 C (24.1 F)n/an/a
Oct35.0 C (95.0 F)-7.8 C (18.0 F)n/an/a
Nov27.8 C (82.0 F)-16.1 C (3.0 F)n/an/a
Dec23.3 C (73.9 F)-26.1 C (-15.0 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Irwin by the year they were set 1,464 records at Irwin still stand. 1900 holds the most, with 100. 02550751001896: 161897: 131900: 1001901: 361902: 281903: 241904: 291905: 131906: 301907: 291908: 321909: 181910: 311911: 281912: 231913: 121914: 401915: 151916: 161917: 371918: 461919: 211920: 341921: 171922: 141923: 281924: 221925: 281926: 281927: 361928: 291929: 331930: 351931: 181932: 251933: 241934: 211935: 161936: 421937: 151938: 151939: 221940: 271941: 171942: 221943: 241944: 81945: 271946: 221947: 161948: 141949: 211950: 251951: 201952: 161953: 151954: 201955: 91956: 101957: 101958: 2189619051912191919261933194019471954
1,464 records at Irwin still stand. 1900 holds the most, with 100.
Standing records at Irwin by the year they were set
Year setStanding records
189616
189713
1900100
190136
190228
190324
190429
190513
190630
190729
190832
190918
191031
191128
191223
191312
191440
191515
191616
191737
191846
191921
192034
192117
192214
192328
192422
192528
192628
192736
192829
192933
193035
193118
193225
193324
193421
193516
193642
193715
193815
193922
194027
194117
194222
194324
19448
194527
194622
194716
194814
194921
195025
195120
195216
195315
195420
19559
195610
195710
19582

All-Time Record Progression

1 new records
When Irwin set new all-time records 1 all-time records were set at Irwin between 25 November 1950 and 25 November 1950. Each dot is a new record. Record daily snowfall25 November 1950: Record daily snowfall 50.8 cm (20.0 in)1950
1 all-time records were set at Irwin between 25 November 1950 and 25 November 1950. Each dot is a new record.
When Irwin set new all-time records
DateKindDetail
1950-11-25Record daily snowfallRecord daily snowfall 50.8 cm (20.0 in)

Wettest Day of Each Month

Jul: 96.3 mm (3.8 in)
Record daily precipitation for each month at Irwin The wettest day on record for each calendar month at Irwin. The most was 96.3 mm (3.8 in) on 18 July 1912. 0255075100 Jan: 39.6 mm (1.6 in), 27 January 1952 Jan Feb: 45.5 mm (1.8 in), 1 February 1951 Feb Mar: 61.0 mm (2.4 in), 6 March 1945 Mar Apr: 59.9 mm (2.4 in), 9 April 1942 Apr May: 44.7 mm (1.8 in), 8 May 1931 May Jun: 87.6 mm (3.4 in), 26 June 1921 Jun Jul: 96.3 mm (3.8 in), 18 July 1912 Jul Aug: 73.7 mm (2.9 in), 5 August 1956 Aug Sep: 64.8 mm (2.6 in), 29 September 1936 Sep Oct: 73.7 mm (2.9 in), 15 October 1954 Oct Nov: 67.3 mm (2.6 in), 4 November 1950 Nov Dec: 63.5 mm (2.5 in), 30 December 1942 Dec
The wettest day on record for each calendar month at Irwin. The most was 96.3 mm (3.8 in) on 18 July 1912.
Record daily precipitation for each month at Irwin
MonthRecord daily precipitation (mm)Date
Jan39.6 mm (1.6 in)27 January 1952
Feb45.5 mm (1.8 in)1 February 1951
Mar61.0 mm (2.4 in)6 March 1945
Apr59.9 mm (2.4 in)9 April 1942
May44.7 mm (1.8 in)8 May 1931
Jun87.6 mm (3.4 in)26 June 1921
Jul96.3 mm (3.8 in)18 July 1912
Aug73.7 mm (2.9 in)5 August 1956
Sep64.8 mm (2.6 in)29 September 1936
Oct73.7 mm (2.9 in)15 October 1954
Nov67.3 mm (2.6 in)4 November 1950
Dec63.5 mm (2.5 in)30 December 1942

Period of Record Coverage

1896 to 1958
Days with data per year at Irwin 61 years of record at Irwin, 1896 to 1958. 14 years have data for under 90 percent of days and are left out of rankings: 1896, 1897, 1900, 1901, 1902, 1913, 1914, 1922 and others. 1896: 115 of 366 days1897: 105 of 365 days1900: 260 of 365 days1901: 310 of 365 days1902: 327 of 365 days1903: 361 of 365 days1904: 349 of 366 days1905: 359 of 365 days1906: 365 of 365 days1907: 363 of 365 days1908: 358 of 366 days1909: 364 of 365 days1910: 341 of 365 days1911: 357 of 365 days1912: 357 of 366 days1913: 241 of 365 days1914: 325 of 365 days1915: 335 of 365 days1916: 356 of 366 days1917: 363 of 365 days1918: 361 of 365 days1919: 364 of 365 days1920: 357 of 366 days1921: 335 of 365 days1922: 313 of 365 days1923: 299 of 365 days1924: 357 of 366 days1925: 364 of 365 days1926: 365 of 365 days1927: 364 of 365 days1928: 366 of 366 days1929: 362 of 365 days1930: 365 of 365 days1931: 365 of 365 days1932: 359 of 366 days1933: 361 of 365 days1934: 361 of 365 days1935: 365 of 365 days1936: 366 of 366 days1937: 326 of 365 days1938: 365 of 365 days1939: 357 of 365 days1940: 361 of 366 days1941: 364 of 365 days1942: 362 of 365 days1943: 363 of 365 days1944: 366 of 366 days1945: 364 of 365 days1946: 363 of 365 days1947: 361 of 365 days1948: 335 of 366 days1949: 364 of 365 days1950: 364 of 365 days1951: 362 of 365 days1952: 361 of 366 days1953: 365 of 365 days1954: 338 of 365 days1955: 324 of 365 days1956: 313 of 366 days1957: 239 of 365 days1958: 59 of 365 days190019101920193019401950
61 years of record at Irwin, 1896 to 1958. 14 years have data for under 90 percent of days and are left out of rankings: 1896, 1897, 1900, 1901, 1902, 1913, 1914, 1922 and others.
Days with data per year at Irwin
YearDays with dataShare of yearComplete
189611531%No
189710529%No
190026071%No
190131085%No
190232790%No
190336199%Yes
190434995%Yes
190535998%Yes
1906365100%Yes
190736399%Yes
190835898%Yes
1909364100%Yes
191034193%Yes
191135798%Yes
191235798%Yes
191324166%No
191432589%No
191533592%Yes
191635697%Yes
191736399%Yes
191836199%Yes
1919364100%Yes
192035798%Yes
192133592%Yes
192231386%No
192329982%No
192435798%Yes
1925364100%Yes
1926365100%Yes
1927364100%Yes
1928366100%Yes
192936299%Yes
1930365100%Yes
1931365100%Yes
193235998%Yes
193336199%Yes
193436199%Yes
1935365100%Yes
1936366100%Yes
193732689%No
1938365100%Yes
193935798%Yes
194036199%Yes
1941364100%Yes
194236299%Yes
194336399%Yes
1944366100%Yes
1945364100%Yes
194636399%Yes
194736199%Yes
194833592%Yes
1949364100%Yes
1950364100%Yes
195136299%Yes
195236199%Yes
1953365100%Yes
195433893%Yes
195532489%No
195631386%No
195723965%No
19585916%No

Latest Records

20
Latest records at Irwin
DateStationRecordValueBeat old record byOld record stoodSignificance
14 March 1958Irwin, USdaily snowfall17.8 cm (7.0 in)7.6 cm (3.0 in)20 years25 of 100 (Routine)
17 February 1958Irwin, USdaily low max-11.1 C (12.0 F)2.8 C (5.0 F)54 years26 of 100 (Routine)
17 February 1958Irwin, USdaily low min (Tie)-21.7 C (-7.1 F)tie54 years5 of 100 (Routine)
14 February 1958Irwin, USdaily low max-3.9 C (25.0 F)1.1 C (2.0 F)52 years22 of 100 (Routine)
14 January 1958Irwin, USdaily rain29.0 mm (1.1 in)2.1 mm (0.08 in)51 years24 of 100 (Routine)
8 January 1958Irwin, USdaily snowfall10.2 cm (4.0 in)1.8 cm (0.7 in)52 years25 of 100 (Routine)
26 December 1957Irwin, USdaily rain22.4 mm (0.9 in)3.3 mm (0.13 in)14 years14 of 100 (Routine)
20 December 1957Irwin, USdaily high min11.1 C (52.0 F)6.7 C (12.1 F)0 years16 of 100 (Routine)
9 December 1957Irwin, USdaily rain22.4 mm (0.9 in)7.7 mm (0.30 in)38 years20 of 100 (Routine)
5 December 1957Irwin, USdaily low min-12.2 C (10.0 F)0.5 C (0.9 F)56 years22 of 100 (Routine)
9 July 1957Irwin, USdaily rain40.9 mm (1.6 in)7.4 mm (0.29 in)28 years20 of 100 (Routine)
3 July 1957Irwin, USdaily low min6.7 C (44.1 F)0.5 C (0.9 F)28 years15 of 100 (Routine)
18 June 1957Irwin, USdaily high max (Tie)34.4 C (93.9 F)tie4 years1 of 100 (Routine)
6 May 1957Irwin, USdaily low min-2.2 C (28.0 F)0.5 C (0.9 F)47 years20 of 100 (Routine)
27 April 1957Irwin, USdaily high max (Tie)31.1 C (88.0 F)tie42 years4 of 100 (Routine)
25 April 1957Irwin, USdaily high min17.2 C (63.0 F)1.1 C (2.0 F)36 years17 of 100 (Routine)
4 April 1957Irwin, USdaily rain30.7 mm (1.2 in)9.1 mm (0.36 in)23 years23 of 100 (Routine)
2 April 1957Irwin, USdaily rain31.5 mm (1.2 in)15.0 mm (0.6 in)8 years27 of 100 (Routine)
27 March 1957Irwin, USdaily rain18.3 mm (0.7 in)0.5 mm (0.02 in)35 years16 of 100 (Routine)
12 March 1957Irwin, USdaily high min10.6 C (51.1 F)0.6 C (1.1 F)55 years23 of 100 (Routine)

Climate Trend

45 complete years, 1903 to 1955
Annual mean temperature at Irwin as warming stripes, 1903 to 1955 One stripe for each of 45 complete years at Irwin, 1903 to 1955. Blue stripes are years cooler than the station's own mean of 10.9 C (51.6 F); red stripes are warmer. The coolest year was 1917, at 8.9 C (48.0 F), and the warmest was 1946, at 12.9 C (55.2 F). The strongest colour marks a difference of 2.0 C (3.6 F). 1903: 10.9 C, 0.0 C from the station mean1904: 10.2 C, -0.7 C from the station mean1905: 11.0 C, +0.1 C from the station mean1906: 12.0 C, +1.1 C from the station mean1907: 10.7 C, -0.2 C from the station mean1908: 11.9 C, +1.1 C from the station mean1909: 11.2 C, +0.3 C from the station mean1910: 10.5 C, -0.4 C from the station mean1911: 12.2 C, +1.3 C from the station mean1912: 10.7 C, -0.2 C from the station mean1916: 10.7 C, -0.2 C from the station mean1917: 8.9 C, -2.0 C from the station mean1918: 9.7 C, -1.1 C from the station mean1919: 10.7 C, -0.2 C from the station mean1920: 9.4 C, -1.5 C from the station mean1924: 9.1 C, -1.8 C from the station mean1925: 10.7 C, -0.2 C from the station mean1926: 9.7 C, -1.2 C from the station mean1927: 10.0 C, -0.8 C from the station mean1928: 9.3 C, -1.6 C from the station mean1929: 9.4 C, -1.5 C from the station mean1930: 10.2 C, -0.7 C from the station mean1931: 11.1 C, +0.2 C from the station mean1932: 11.4 C, +0.5 C from the station mean1933: 11.8 C, +0.9 C from the station mean1934: 11.1 C, +0.3 C from the station mean1935: 10.5 C, -0.4 C from the station mean1936: 10.6 C, -0.2 C from the station mean1938: 11.7 C, +0.8 C from the station mean1939: 11.8 C, +0.9 C from the station mean1940: 10.1 C, -0.8 C from the station mean1941: 11.3 C, +0.4 C from the station mean1942: 10.9 C, +0.1 C from the station mean1943: 10.2 C, -0.7 C from the station mean1944: 11.2 C, +0.3 C from the station mean1945: 11.2 C, +0.3 C from the station mean1946: 12.9 C, +2.0 C from the station mean1947: 10.8 C, -0.1 C from the station mean1949: 12.4 C, +1.5 C from the station mean1950: 10.6 C, -0.3 C from the station mean1951: 11.3 C, +0.4 C from the station mean1952: 11.9 C, +1.0 C from the station mean1953: 12.2 C, +1.3 C from the station mean1954: 11.7 C, +0.8 C from the station mean1955: 11.7 C, +0.8 C from the station mean19031910191519201925193019351940194519501955
One stripe for each of 45 complete years at Irwin, 1903 to 1955. Blue stripes are years cooler than the station's own mean of 10.9 C (51.6 F); red stripes are warmer. The coolest year was 1917, at 8.9 C (48.0 F), and the warmest was 1946, at 12.9 C (55.2 F). The strongest colour marks a difference of 2.0 C (3.6 F).
Annual mean temperature at Irwin as warming stripes, 1903 to 1955
YearAnnual mean temperatureDifference from the station mean
190310.9 C-0.02 C
190410.2 C-0.70 C
190511.0 C+0.12 C
190612.0 C+1.15 C
190710.7 C-0.16 C
190811.9 C+1.07 C
190911.2 C+0.31 C
191010.5 C-0.37 C
191112.2 C+1.33 C
191210.7 C-0.20 C
191610.7 C-0.15 C
19178.9 C-1.97 C
19189.7 C-1.14 C
191910.7 C-0.16 C
19209.4 C-1.49 C
19249.1 C-1.78 C
192510.7 C-0.20 C
19269.7 C-1.20 C
192710.0 C-0.83 C
19289.3 C-1.58 C
19299.4 C-1.49 C
193010.2 C-0.67 C
193111.1 C+0.20 C
193211.4 C+0.50 C
193311.8 C+0.92 C
193411.1 C+0.27 C
193510.5 C-0.37 C
193610.6 C-0.23 C
193811.7 C+0.85 C
193911.8 C+0.91 C
194010.1 C-0.77 C
194111.3 C+0.42 C
194210.9 C+0.06 C
194310.2 C-0.70 C
194411.2 C+0.29 C
194511.2 C+0.33 C
194612.9 C+2.00 C
194710.8 C-0.08 C
194912.4 C+1.48 C
195010.6 C-0.29 C
195111.3 C+0.39 C
195211.9 C+0.98 C
195312.2 C+1.35 C
195411.7 C+0.83 C
195511.7 C+0.79 C

The annual mean temperature here has risen by 0.18 C (0.01 to 0.35) per decade over 1903 to 1955. In Fahrenheit: 0.32 F (0.01 to 0.63) per decade. The slope is a straight line fitted to 45 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Irwin
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.18 C (0.01 to 0.35) per decade0.32 F (0.01 to 0.63) per decade1903 to 195545Rise
Mean daily maximum0.1 C (-0.1 to 0.4) per decade0.2 F (-0.2 to 0.7) per decade1903 to 195545Not clearly different from zero
Mean daily minimum0.2 C (0.1 to 0.4) per decade0.4 F (0.2 to 0.7) per decade1903 to 195545Rise

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

1896 to 1958
Yearly extremes at Irwin: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)40.0 C (104.0 F)191135.6 C (96.1 F)61
Coldest night (TNn)-30.0 C (-22.0 F)1912-20.6 C (-5.1 F)61
Wettest day (Rx1day)96.3 mm (3.8 in)191250.8 mm (2.0 in)63
Wettest five days (Rx5day)159.0 mm (6.3 in)192178.0 mm (3.1 in)63
Longest dry spell (CDD)37 days189716 days63

Hottest day (TXx)

Hottest day (TXx) at Irwin by year The hottest day of the year at Irwin, 1896 to 1958. The record is 40.0 C (104.0 F) in 1911, marked on the chart; the median year is 35.6 C (96.1 F). 10203040190019201940Record: 40.0 C (104.0 F) in 1911
The hottest day of the year at Irwin, 1896 to 1958. The record is 40.0 C (104.0 F) in 1911, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Irwin by year
YearHottest day (TXx)
189636.7 C (98.1 F)
189732.2 C (90.0 F)
1898n/a
1899n/a
190037.8 C (100.0 F)
190136.7 C (98.1 F)
190235.6 C (96.1 F)
190337.2 C (99.0 F)
190435.6 C (96.1 F)
190535.6 C (96.1 F)
190637.2 C (99.0 F)
190733.9 C (93.0 F)
190837.2 C (99.0 F)
190933.9 C (93.0 F)
191035.6 C (96.1 F)
191140.0 C (104.0 F)
191233.3 C (91.9 F)
191335.0 C (95.0 F)
191435.6 C (96.1 F)
191533.9 C (93.0 F)
191635.6 C (96.1 F)
191735.0 C (95.0 F)
191839.4 C (102.9 F)
191935.0 C (95.0 F)
192030.0 C (86.0 F)
192134.4 C (93.9 F)
192235.0 C (95.0 F)
192332.8 C (91.0 F)
192435.6 C (96.1 F)
192536.1 C (97.0 F)
192638.9 C (102.0 F)
192735.0 C (95.0 F)
192833.9 C (93.0 F)
192933.9 C (93.0 F)
193037.8 C (100.0 F)
193136.7 C (98.1 F)
193236.1 C (97.0 F)
193336.1 C (97.0 F)
193436.7 C (98.1 F)
193533.3 C (91.9 F)
193638.9 C (102.0 F)
193735.0 C (95.0 F)
193834.4 C (93.9 F)
193936.7 C (98.1 F)
194034.4 C (93.9 F)
194135.0 C (95.0 F)
194236.1 C (97.0 F)
194334.4 C (93.9 F)
194435.6 C (96.1 F)
194533.9 C (93.0 F)
194634.4 C (93.9 F)
194733.3 C (91.9 F)
194837.2 C (99.0 F)
194935.6 C (96.1 F)
195033.3 C (91.9 F)
195134.4 C (93.9 F)
195235.6 C (96.1 F)
195338.9 C (102.0 F)
195436.1 C (97.0 F)
195537.2 C (99.0 F)
195633.9 C (93.0 F)
195734.4 C (93.9 F)
195815.0 C (59.0 F)

Coldest night (TNn)

Coldest night (TNn) at Irwin by year The coldest night of the year at Irwin, 1896 to 1958. The record is -30.0 C (-22.0 F) in 1912, marked on the chart; the median year is -20.6 C (-5.1 F). -30-25-20-15-10190019201940Record: -30.0 C (-22.0 F) in 1912
The coldest night of the year at Irwin, 1896 to 1958. The record is -30.0 C (-22.0 F) in 1912, marked on the chart; the median year is -20.6 C (-5.1 F).
Coldest night (TNn) at Irwin by year
YearColdest night (TNn)
1896-11.1 C (12.0 F)
1897-20.0 C (-4.0 F)
1898n/a
1899n/a
1900-12.2 C (10.0 F)
1901-22.8 C (-9.0 F)
1902-20.0 C (-4.0 F)
1903-20.6 C (-5.1 F)
1904-27.2 C (-17.0 F)
1905-24.4 C (-11.9 F)
1906-21.1 C (-6.0 F)
1907-25.6 C (-14.1 F)
1908-19.4 C (-2.9 F)
1909-18.9 C (-2.0 F)
1910-20.0 C (-4.0 F)
1911-15.6 C (3.9 F)
1912-30.0 C (-22.0 F)
1913-16.1 C (3.0 F)
1914-22.2 C (-8.0 F)
1915-18.9 C (-2.0 F)
1916-25.6 C (-14.1 F)
1917-26.1 C (-15.0 F)
1918-26.7 C (-16.1 F)
1919-23.3 C (-9.9 F)
1920-18.9 C (-2.0 F)
1921-14.4 C (6.1 F)
1922-16.7 C (1.9 F)
1923-20.0 C (-4.0 F)
1924-19.4 C (-2.9 F)
1925-25.0 C (-13.0 F)
1926-22.8 C (-9.0 F)
1927-18.9 C (-2.0 F)
1928-19.4 C (-2.9 F)
1929-22.8 C (-9.0 F)
1930-20.6 C (-5.1 F)
1931-12.8 C (9.0 F)
1932-21.1 C (-6.0 F)
1933-20.6 C (-5.1 F)
1934-27.2 C (-17.0 F)
1935-20.6 C (-5.1 F)
1936-26.1 C (-15.0 F)
1937-17.8 C (0.0 F)
1938-16.1 C (3.0 F)
1939-16.7 C (1.9 F)
1940-22.8 C (-9.0 F)
1941-17.8 C (0.0 F)
1942-25.6 C (-14.1 F)
1943-23.3 C (-9.9 F)
1944-22.2 C (-8.0 F)
1945-22.8 C (-9.0 F)
1946-20.0 C (-4.0 F)
1947-17.8 C (0.0 F)
1948-24.4 C (-11.9 F)
1949-16.1 C (3.0 F)
1950-22.2 C (-8.0 F)
1951-22.2 C (-8.0 F)
1952-16.1 C (3.0 F)
1953-12.8 C (9.0 F)
1954-16.7 C (1.9 F)
1955-23.9 C (-11.0 F)
1956-15.6 C (3.9 F)
1957-21.7 C (-7.1 F)
1958-21.7 C (-7.1 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Irwin by year The wettest day of the year at Irwin, 1896 to 1958. The record is 96.3 mm (3.8 in) in 1912, marked on the chart; the median year is 50.8 mm (2.0 in). 20406080100190019201940Record: 96.3 mm (3.8 in) in 1912
The wettest day of the year at Irwin, 1896 to 1958. The record is 96.3 mm (3.8 in) in 1912, marked on the chart; the median year is 50.8 mm (2.0 in).
Wettest day (Rx1day) at Irwin by year
YearWettest day (Rx1day)
189650.3 mm (2.0 in)
189748.8 mm (1.9 in)
189855.4 mm (2.2 in)
189941.9 mm (1.6 in)
190047.2 mm (1.9 in)
190157.7 mm (2.3 in)
190263.5 mm (2.5 in)
190394.7 mm (3.7 in)
190444.5 mm (1.8 in)
190553.3 mm (2.1 in)
190650.8 mm (2.0 in)
190750.8 mm (2.0 in)
190838.1 mm (1.5 in)
190940.4 mm (1.6 in)
191031.0 mm (1.2 in)
191157.2 mm (2.3 in)
191296.3 mm (3.8 in)
191340.4 mm (1.6 in)
191450.0 mm (2.0 in)
191534.3 mm (1.4 in)
191634.8 mm (1.4 in)
191739.6 mm (1.6 in)
191850.8 mm (2.0 in)
191958.9 mm (2.3 in)
192044.7 mm (1.8 in)
192187.6 mm (3.4 in)
192255.9 mm (2.2 in)
192341.1 mm (1.6 in)
192470.4 mm (2.8 in)
192535.1 mm (1.4 in)
192648.3 mm (1.9 in)
192750.8 mm (2.0 in)
192835.6 mm (1.4 in)
192950.8 mm (2.0 in)
193035.6 mm (1.4 in)
193145.7 mm (1.8 in)
193235.8 mm (1.4 in)
193338.1 mm (1.5 in)
193450.8 mm (2.0 in)
193538.1 mm (1.5 in)
193664.8 mm (2.6 in)
193747.2 mm (1.9 in)
193851.6 mm (2.0 in)
193931.0 mm (1.2 in)
194056.6 mm (2.2 in)
194149.8 mm (2.0 in)
194263.5 mm (2.5 in)
194351.8 mm (2.0 in)
194444.5 mm (1.8 in)
194561.0 mm (2.4 in)
194645.7 mm (1.8 in)
194754.6 mm (2.1 in)
194850.8 mm (2.0 in)
194953.1 mm (2.1 in)
195078.2 mm (3.1 in)
195156.4 mm (2.2 in)
195263.5 mm (2.5 in)
195354.1 mm (2.1 in)
195473.7 mm (2.9 in)
195567.3 mm (2.6 in)
195673.7 mm (2.9 in)
195740.9 mm (1.6 in)
195829.0 mm (1.1 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Irwin by year The wettest five days of the year at Irwin, 1896 to 1958. The record is 159.0 mm (6.3 in) in 1921, marked on the chart; the median year is 78.0 mm (3.1 in). 050100150200190019201940Record: 159.0 mm (6.3 in) in 1921
The wettest five days of the year at Irwin, 1896 to 1958. The record is 159.0 mm (6.3 in) in 1921, marked on the chart; the median year is 78.0 mm (3.1 in).
Wettest five days (Rx5day) at Irwin by year
YearWettest five days (Rx5day)
189657.4 mm (2.3 in)
189755.4 mm (2.2 in)
189889.0 mm (3.5 in)
189960.8 mm (2.4 in)
190051.6 mm (2.0 in)
190147.5 mm (1.9 in)
190280.3 mm (3.2 in)
1903112.4 mm (4.4 in)
190475.8 mm (3.0 in)
190565.4 mm (2.6 in)
190692.9 mm (3.7 in)
190789.9 mm (3.5 in)
190850.5 mm (2.0 in)
190951.3 mm (2.0 in)
191050.3 mm (2.0 in)
191197.0 mm (3.8 in)
1912152.9 mm (6.0 in)
191362.5 mm (2.5 in)
191483.9 mm (3.3 in)
191578.0 mm (3.1 in)
191656.6 mm (2.2 in)
191768.6 mm (2.7 in)
191895.1 mm (3.7 in)
191965.5 mm (2.6 in)
192073.4 mm (2.9 in)
1921159.0 mm (6.3 in)
192280.8 mm (3.2 in)
192380.0 mm (3.1 in)
192479.6 mm (3.1 in)
192545.3 mm (1.8 in)
1926121.7 mm (4.8 in)
192767.3 mm (2.6 in)
192876.3 mm (3.0 in)
192958.9 mm (2.3 in)
193050.1 mm (2.0 in)
193163.7 mm (2.5 in)
193239.1 mm (1.5 in)
193367.1 mm (2.6 in)
193496.1 mm (3.8 in)
193583.0 mm (3.3 in)
1936110.2 mm (4.3 in)
1937103.6 mm (4.1 in)
193886.6 mm (3.4 in)
193975.1 mm (3.0 in)
194082.2 mm (3.2 in)
194187.4 mm (3.4 in)
194298.1 mm (3.9 in)
1943100.2 mm (3.9 in)
194465.9 mm (2.6 in)
1945108.5 mm (4.3 in)
194667.5 mm (2.7 in)
194777.5 mm (3.1 in)
1948111.0 mm (4.4 in)
194979.8 mm (3.1 in)
195082.5 mm (3.2 in)
1951110.5 mm (4.4 in)
195276.7 mm (3.0 in)
195368.6 mm (2.7 in)
1954108.8 mm (4.3 in)
195593.7 mm (3.7 in)
1956122.0 mm (4.8 in)
195768.1 mm (2.7 in)
195837.6 mm (1.5 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Irwin by year The longest dry spell of the year at Irwin, 1896 to 1958. The record is 37 days in 1897, marked on the chart; the median year is 16 days. 010203040190019201940Record: 37 days in 1897
The longest dry spell of the year at Irwin, 1896 to 1958. The record is 37 days in 1897, marked on the chart; the median year is 16 days.
Longest dry spell (CDD) at Irwin by year
YearLongest dry spell (CDD)
18969 days
189737 days
189810 days
189914 days
190022 days
190111 days
190223 days
190319 days
190414 days
190512 days
190616 days
190710 days
190819 days
190916 days
191014 days
191111 days
191217 days
191314 days
191420 days
191518 days
191611 days
191722 days
191817 days
191913 days
192023 days
192116 days
192233 days
192315 days
192423 days
192519 days
192619 days
192712 days
192812 days
192915 days
193029 days
193110 days
193216 days
193317 days
193421 days
193512 days
193612 days
193713 days
193813 days
193925 days
194013 days
194119 days
194217 days
194326 days
194416 days
194513 days
194613 days
194726 days
194816 days
194915 days
195013 days
195119 days
195224 days
195324 days
195414 days
195521 days
195613 days
195726 days
195813 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

45 years with a frost

Across 45 years with a frost, the median last spring frost at Irwin falls on 10 May and the median first autumn frost on 7 October, which leaves a median of 152 days between them.

Fitted over all years, the growing season changes by +3.4 days per decade at this station.

Frost dates and growing season at Irwin
MeasureMedian, all yearsEarliest periodRecent period (1924 to 1955)Recent against earliestFitted trend
Last spring frost10 Mayn/a11 Mayn/a-0.6 days per decade
First autumn frost7 Octobern/a8 Octobern/a+2.7 days per decade
Growing days152 daysn/a153 daysn/a+3.4 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

54 years, 1897 to 1957

A day with at least 49.5 mm (1.9 in) of rain is expected about once in 2 years. A day with at least 95.2 mm (3.7 in) of rain is expected about once in 100 years.

Rainfall return levels at Irwin: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years49.5 mm (1.9 in)
5 years62.0 mm (2.4 in)
10 years70.1 mm (2.8 in)
25 years80.3 mm (3.2 in)
50 years87.8 mm (3.5 in)
100 years95.2 mm (3.7 in)Longer than the 54 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, 54 years of values from 1897 to 1957.

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: 96.3 mm (3.8 in) in 1912; 87.6 mm (3.4 in) in 1921; 78.2 mm (3.1 in) in 1950.

Station Changes

1 suspected

One change was suspected in the annual mean temperature of Irwin, at 1932. Each is measured against neighbouring stations.

  • Relative to 5 neighbouring stations, the station's annual mean temperature from 1932 ran 0.6 C (1.2 F) higher than in the years before (likely change).
Suspected changes in the annual mean temperature at Irwin, against neighbouring stations
YearShift (C)Shift (F)StrengthNeighbours
1932+0.6+1.2likely5

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.

Download the Data

  • Data for Irwin standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Irwin 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.

Data as of . Last revised (2025-12-31).