Built 2026-10-15 (15 October 2026)

Mortlake Racecourse Weather Records (ASN00090176)

Record envelope, standing records and threshold days for Mortlake Racecourse (ASN00090176), Australia, with 37 years of record.

Key Facts for Mortlake Racecourse

  • Mortlake Racecourse (ASN00090176) is a weather station in Australia at -38.07 latitude and 142.77 longitude, 130 m (427 ft) above sea level.
  • The station reports from 1990 to 2026, 37 years of record.
  • 1,464 records set at Mortlake Racecourse still stand.
  • Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
  • Mortlake Racecourse set a monthly record high minimum temperature of 15.5 C (59.9 F) on 30 September 2026 (provisional).

Provisional Records

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

About the Station

  • Location: Australia, -38.07 latitude, 142.77 longitude.
  • Elevation: 130 m (427 ft).
  • Period of record: 1990 to 2026, 37 years.
  • Eligible elements: tmax, tmin, prcp.

Daily Record Envelope and 2026

18 days at or beyond a record
Daily record high and record low at Mortlake Racecourse, with 2026 drawn through them The band shows the record high and record low for each calendar day at Mortlake Racecourse. The lines show the 2026 daily maximum and minimum. 18 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -200204060 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Mortlake Racecourse. The lines show the 2026 daily maximum and minimum. 18 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Mortlake Racecourse, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan46.3 C (115.3 F)1.1 C (34.0 F)46.3 C (115.3 F)2.8 C (37.0 F)
Feb46.0 C (114.8 F)2.0 C (35.6 F)36.8 C (98.2 F)3.3 C (37.9 F)
Mar41.5 C (106.7 F)-1.3 C (29.7 F)32.7 C (90.9 F)4.2 C (39.6 F)
Apr36.9 C (98.4 F)-2.5 C (27.5 F)28.4 C (83.1 F)1.7 C (35.1 F)
May28.5 C (83.3 F)-3.1 C (26.4 F)28.5 C (83.3 F)-0.3 C (31.5 F)
Jun23.2 C (73.8 F)-5.0 C (23.0 F)17.6 C (63.7 F)-1.1 C (30.0 F)
Jul19.1 C (66.4 F)-5.3 C (22.5 F)16.2 C (61.2 F)-2.4 C (27.7 F)
Aug23.4 C (74.1 F)-4.4 C (24.1 F)18.8 C (65.8 F)-0.5 C (31.1 F)
Sep28.4 C (83.1 F)-3.0 C (26.6 F)25.5 C (77.9 F)-1.2 C (29.8 F)
Oct35.8 C (96.4 F)-3.9 C (25.0 F)16.0 C (60.8 F)10.3 C (50.5 F)
Nov38.3 C (100.9 F)-1.4 C (29.5 F)n/an/a
Dec44.0 C (111.2 F)-0.6 C (30.9 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Mortlake Racecourse by the year they were set 1,464 records at Mortlake Racecourse still stand. 1994 holds the most, with 59. 02040601990: 231991: 471992: 381993: 381994: 591995: 531996: 441997: 441998: 381999: 352000: 252001: 502002: 452003: 332004: 372005: 442006: 562007: 382008: 332009: 452010: 362011: 432012: 372013: 442014: 452015: 522016: 252017: 382018: 412019: 492020: 422021: 292022: 262023: 232024: 472025: 382026: 241990199419982002200620102014201820222026
1,464 records at Mortlake Racecourse still stand. 1994 holds the most, with 59.
Standing records at Mortlake Racecourse by the year they were set
Year setStanding records
199023
199147
199238
199338
199459
199553
199644
199744
199838
199935
200025
200150
200245
200333
200437
200544
200656
200738
200833
200945
201036
201143
201237
201344
201445
201552
201625
201738
201841
201949
202042
202129
202226
202323
202447
202538
202624

All-Time Record Progression

1 new records
When Mortlake Racecourse set new all-time records 1 all-time records were set at Mortlake Racecourse between 27 January 2026 and 27 January 2026. Each dot is a new record. Record high maximum temperature27 January 2026: Record high maximum temperature 46.3 C (115.3 F)
1 all-time records were set at Mortlake Racecourse between 27 January 2026 and 27 January 2026. Each dot is a new record.
When Mortlake Racecourse set new all-time records
DateKindDetail
2026-01-27Record high maximum temperatureRecord high maximum temperature 46.3 C (115.3 F)

Wettest Day of Each Month

Dec: 67.0 mm (2.6 in)
Record daily precipitation for each month at Mortlake Racecourse The wettest day on record for each calendar month at Mortlake Racecourse. The most was 67.0 mm (2.6 in) on 13 December 2008. 020406080 Jan: 59.8 mm (2.4 in), 12 January 2011 Jan Feb: 49.0 mm (1.9 in), 3 February 2005 Feb Mar: 30.8 mm (1.2 in), 20 March 2003 Mar Apr: 36.6 mm (1.4 in), 25 April 2017 Apr May: 47.4 mm (1.9 in), 11 May 2018 May Jun: 41.2 mm (1.6 in), 8 June 2025 Jun Jul: 52.2 mm (2.1 in), 8 July 2008 Jul Aug: 42.6 mm (1.7 in), 12 August 2010 Aug Sep: 33.6 mm (1.3 in), 14 September 2016 Sep Oct: 50.0 mm (2.0 in), 13 October 2022 Oct Nov: 39.4 mm (1.6 in), 4 November 2007 Nov Dec: 67.0 mm (2.6 in), 13 December 2008 Dec
The wettest day on record for each calendar month at Mortlake Racecourse. The most was 67.0 mm (2.6 in) on 13 December 2008.
Record daily precipitation for each month at Mortlake Racecourse
MonthRecord daily precipitation (mm)Date
Jan59.8 mm (2.4 in)12 January 2011
Feb49.0 mm (1.9 in)3 February 2005
Mar30.8 mm (1.2 in)20 March 2003
Apr36.6 mm (1.4 in)25 April 2017
May47.4 mm (1.9 in)11 May 2018
Jun41.2 mm (1.6 in)8 June 2025
Jul52.2 mm (2.1 in)8 July 2008
Aug42.6 mm (1.7 in)12 August 2010
Sep33.6 mm (1.3 in)14 September 2016
Oct50.0 mm (2.0 in)13 October 2022
Nov39.4 mm (1.6 in)4 November 2007
Dec67.0 mm (2.6 in)13 December 2008

Period of Record Coverage

1990 to 2026
Days with data per year at Mortlake Racecourse 37 years of record at Mortlake Racecourse, 1990 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1990, 2026. 1990: 168 of 365 days1991: 334 of 365 days1992: 345 of 366 days1993: 353 of 365 days1994: 350 of 365 days1995: 351 of 365 days1996: 358 of 366 days1997: 358 of 365 days1998: 331 of 365 days1999: 339 of 365 days2000: 358 of 366 days2001: 359 of 365 days2002: 362 of 365 days2003: 364 of 365 days2004: 366 of 366 days2005: 365 of 365 days2006: 365 of 365 days2007: 365 of 365 days2008: 366 of 366 days2009: 365 of 365 days2010: 365 of 365 days2011: 365 of 365 days2012: 366 of 366 days2013: 364 of 365 days2014: 363 of 365 days2015: 364 of 365 days2016: 366 of 366 days2017: 365 of 365 days2018: 365 of 365 days2019: 364 of 365 days2020: 358 of 366 days2021: 364 of 365 days2022: 364 of 365 days2023: 365 of 365 days2024: 364 of 366 days2025: 358 of 365 days2026: 273 of 365 days19901995200020052010201520202025
37 years of record at Mortlake Racecourse, 1990 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1990, 2026.
Days with data per year at Mortlake Racecourse
YearDays with dataShare of yearComplete
199016846%No
199133492%Yes
199234594%Yes
199335397%Yes
199435096%Yes
199535196%Yes
199635898%Yes
199735898%Yes
199833191%Yes
199933993%Yes
200035898%Yes
200135998%Yes
200236299%Yes
2003364100%Yes
2004366100%Yes
2005365100%Yes
2006365100%Yes
2007365100%Yes
2008366100%Yes
2009365100%Yes
2010365100%Yes
2011365100%Yes
2012366100%Yes
2013364100%Yes
201436399%Yes
2015364100%Yes
2016366100%Yes
2017365100%Yes
2018365100%Yes
2019364100%Yes
202035898%Yes
2021364100%Yes
2022364100%Yes
2023365100%Yes
202436499%Yes
202535898%Yes
202627375%No

Latest Records

20
Latest records at Mortlake Racecourse
DateStationRecordValueBeat old record byOld record stoodSignificance
30 September 2026Mortlake Racecourse, AUmonthly high min (Provisional)15.5 C (59.9 F)1.0 C (1.8 F)36 years26 of 100 (Routine)
27 September 2026Mortlake Racecourse, AUdaily low min (Provisional)-0.7 C (30.7 F)1.0 C (1.8 F)1 year6 of 100 (Routine)
25 September 2026Mortlake Racecourse, AUdaily high max (Provisional)21.8 C (71.2 F)0.9 C (1.6 F)17 years10 of 100 (Routine)
25 September 2026Mortlake Racecourse, AUdaily high min (Provisional)12.9 C (55.2 F)0.8 C (1.4 F)12 years8 of 100 (Routine)
23 September 2026Mortlake Racecourse, AUdaily low min (Provisional)-1.0 C (30.2 F)1.6 C (2.9 F)28 years15 of 100 (Routine)
20 September 2026Mortlake Racecourse, AUdaily high max (Provisional)25.5 C (77.9 F)1.6 C (2.9 F)7 years10 of 100 (Routine)
8 September 2026Mortlake Racecourse, AUdaily low min (Provisional)-1.0 C (30.2 F)1.1 C (2.0 F)23 years12 of 100 (Routine)
19 August 2026Mortlake Racecourse, AUdaily high max (Provisional)18.5 C (65.3 F)0.3 C (0.5 F)16 years9 of 100 (Routine)
14 August 2026Mortlake Racecourse, AUdaily high min9.9 C (49.8 F)0.4 C (0.7 F)1 year4 of 100 (Routine)
16 July 2026Mortlake Racecourse, AUdaily high min9.8 C (49.6 F)0.9 C (1.6 F)7 years8 of 100 (Routine)
13 July 2026Mortlake Racecourse, AUdaily high min (Tie)8.9 C (48.0 F)tie36 years3 of 100 (Routine)
12 July 2026Mortlake Racecourse, AUdaily rain11.2 mm (0.4 in)2.6 mm (0.10 in)16 years14 of 100 (Routine)
7 July 2026Mortlake Racecourse, AUdaily low min-2.4 C (27.7 F)0.4 C (0.7 F)1 year4 of 100 (Routine)
30 June 2026Mortlake Racecourse, AUdaily high min11.1 C (52.0 F)0.3 C (0.5 F)16 years8 of 100 (Routine)
18 June 2026Mortlake Racecourse, AUdaily high min14.3 C (57.7 F)4.2 C (7.6 F)29 years24 of 100 (Routine)
17 June 2026Mortlake Racecourse, AUdaily high min14.1 C (57.4 F)4.8 C (8.6 F)13 years22 of 100 (Routine)
17 June 2026Mortlake Racecourse, AUdaily high max17.6 C (63.7 F)1.4 C (2.5 F)7 years12 of 100 (Routine)
16 June 2026Mortlake Racecourse, AUdaily rain12.2 mm (0.5 in)4.0 mm (0.16 in)11 years14 of 100 (Routine)
15 June 2026Mortlake Racecourse, AUdaily low min (Tie)-1.1 C (30.0 F)tie19 years2 of 100 (Routine)
13 June 2026Mortlake Racecourse, AUmonthly high min14.5 C (58.1 F)0.2 C (0.4 F)31 years22 of 100 (Routine)

Climate Trend

33 complete years, 1992 to 2025
Annual mean temperature at Mortlake Racecourse as warming stripes, 1992 to 2025 One stripe for each of 33 complete years at Mortlake Racecourse, 1992 to 2025. Blue stripes are years cooler than the station's own mean of 13.5 C (56.3 F); red stripes are warmer. The coolest year was 1996, at 12.5 C (54.4 F), and the warmest was 2014, at 14.2 C (57.6 F). The strongest colour marks a difference of 1.1 C (2.0 F). 1992: 12.8 C, -0.7 C from the station mean1993: 13.0 C, -0.5 C from the station mean1994: 12.8 C, -0.7 C from the station mean1995: 12.7 C, -0.8 C from the station mean1996: 12.5 C, -1.1 C from the station mean1997: 13.4 C, -0.1 C from the station mean1998: 12.8 C, -0.7 C from the station mean2000: 14.0 C, +0.5 C from the station mean2001: 13.3 C, -0.2 C from the station mean2002: 13.1 C, -0.5 C from the station mean2003: 13.1 C, -0.5 C from the station mean2004: 12.8 C, -0.7 C from the station mean2005: 13.7 C, +0.2 C from the station mean2006: 13.3 C, -0.3 C from the station mean2007: 14.2 C, +0.7 C from the station mean2008: 13.3 C, -0.2 C from the station mean2009: 13.8 C, +0.3 C from the station mean2010: 13.4 C, -0.1 C from the station mean2011: 13.6 C, +0.1 C from the station mean2012: 13.8 C, +0.3 C from the station mean2013: 14.1 C, +0.6 C from the station mean2014: 14.2 C, +0.7 C from the station mean2015: 13.8 C, +0.3 C from the station mean2016: 13.9 C, +0.4 C from the station mean2017: 14.0 C, +0.5 C from the station mean2018: 14.1 C, +0.6 C from the station mean2019: 13.9 C, +0.4 C from the station mean2020: 13.3 C, -0.2 C from the station mean2021: 13.3 C, -0.2 C from the station mean2022: 13.9 C, +0.4 C from the station mean2023: 13.9 C, +0.4 C from the station mean2024: 14.0 C, +0.4 C from the station mean2025: 14.1 C, +0.6 C from the station mean19921995200020052010201520202025
One stripe for each of 33 complete years at Mortlake Racecourse, 1992 to 2025. Blue stripes are years cooler than the station's own mean of 13.5 C (56.3 F); red stripes are warmer. The coolest year was 1996, at 12.5 C (54.4 F), and the warmest was 2014, at 14.2 C (57.6 F). The strongest colour marks a difference of 1.1 C (2.0 F).
Annual mean temperature at Mortlake Racecourse as warming stripes, 1992 to 2025
YearAnnual mean temperatureDifference from the station mean
199212.8 C-0.68 C
199313.0 C-0.52 C
199412.8 C-0.68 C
199512.7 C-0.77 C
199612.5 C-1.05 C
199713.4 C-0.07 C
199812.8 C-0.71 C
200014.0 C+0.50 C
200113.3 C-0.23 C
200213.1 C-0.45 C
200313.1 C-0.45 C
200412.8 C-0.70 C
200513.7 C+0.18 C
200613.3 C-0.25 C
200714.2 C+0.67 C
200813.3 C-0.24 C
200913.8 C+0.29 C
201013.4 C-0.10 C
201113.6 C+0.07 C
201213.8 C+0.28 C
201314.1 C+0.61 C
201414.2 C+0.70 C
201513.8 C+0.28 C
201613.9 C+0.40 C
201714.0 C+0.47 C
201814.1 C+0.63 C
201913.9 C+0.41 C
202013.3 C-0.17 C
202113.3 C-0.17 C
202213.9 C+0.39 C
202313.9 C+0.36 C
202414.0 C+0.45 C
202514.1 C+0.57 C

The annual mean temperature here has risen by 0.4 C (0.2 to 0.5) per decade over 1992 to 2025. In Fahrenheit: 0.7 F (0.4 to 0.9) per decade. The slope is a straight line fitted to 33 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Mortlake Racecourse
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.4 C (0.2 to 0.5) per decade0.7 F (0.4 to 0.9) per decade1992 to 202533Rise
Mean daily maximum0.5 C (0.3 to 0.7) per decade0.9 F (0.5 to 1.2) per decade1992 to 202533Rise
Mean daily minimum0.2 C (0.1 to 0.4) per decade0.4 F (0.2 to 0.7) per decade1992 to 202533Rise

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

1990 to 2026
Yearly extremes at Mortlake Racecourse: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)46.3 C (115.3 F)202641.9 C (107.4 F)37
Coldest night (TNn)-5.3 C (22.5 F)1994-2.3 C (27.9 F)37
Wettest day (Rx1day)67.0 mm (2.6 in)200833.0 mm (1.3 in)33
Wettest five days (Rx5day)123.8 mm (4.9 in)201153.4 mm (2.1 in)33
Longest dry spell (CDD)44 days201422 days33

Hottest day (TXx)

Hottest day (TXx) at Mortlake Racecourse by year The hottest day of the year at Mortlake Racecourse, 1990 to 2026. The record is 46.3 C (115.3 F) in 2026, marked on the chart; the median year is 41.9 C (107.4 F). 354045501990200020102020Record: 46.3 C (115.3 F) in 2026
The hottest day of the year at Mortlake Racecourse, 1990 to 2026. The record is 46.3 C (115.3 F) in 2026, marked on the chart; the median year is 41.9 C (107.4 F).
Hottest day (TXx) at Mortlake Racecourse by year
YearHottest day (TXx)
199037.9 C (100.2 F)
199140.7 C (105.3 F)
199242.6 C (108.7 F)
199338.3 C (100.9 F)
199438.5 C (101.3 F)
199541.4 C (106.5 F)
199639.9 C (103.8 F)
199742.1 C (107.8 F)
199841.9 C (107.4 F)
199937.0 C (98.6 F)
200040.2 C (104.4 F)
200141.1 C (106.0 F)
200236.1 C (97.0 F)
200342.0 C (107.6 F)
200441.6 C (106.9 F)
200539.1 C (102.4 F)
200643.0 C (109.4 F)
200741.9 C (107.4 F)
200840.3 C (104.5 F)
200946.0 C (114.8 F)
201044.0 C (111.2 F)
201136.6 C (97.9 F)
201242.7 C (108.9 F)
201342.8 C (109.0 F)
201444.0 C (111.2 F)
201543.4 C (110.1 F)
201642.0 C (107.6 F)
201740.3 C (104.5 F)
201843.2 C (109.8 F)
201944.0 C (111.2 F)
202042.6 C (108.7 F)
202140.0 C (104.0 F)
202238.3 C (100.9 F)
202337.5 C (99.5 F)
202442.6 C (108.7 F)
202542.6 C (108.7 F)
202646.3 C (115.3 F)

Coldest night (TNn)

Coldest night (TNn) at Mortlake Racecourse by year The coldest night of the year at Mortlake Racecourse, 1990 to 2026. The record is -5.3 C (22.5 F) in 1994, marked on the chart; the median year is -2.3 C (27.9 F). -6-4-201990200020102020Record: -5.3 C (22.5 F) in 1994
The coldest night of the year at Mortlake Racecourse, 1990 to 2026. The record is -5.3 C (22.5 F) in 1994, marked on the chart; the median year is -2.3 C (27.9 F).
Coldest night (TNn) at Mortlake Racecourse by year
YearColdest night (TNn)
1990-1.2 C (29.8 F)
1991-1.3 C (29.7 F)
1992-0.6 C (30.9 F)
1993-2.3 C (27.9 F)
1994-5.3 C (22.5 F)
1995-2.2 C (28.0 F)
1996-5.0 C (23.0 F)
1997-4.4 C (24.1 F)
1998-2.1 C (28.2 F)
1999-1.6 C (29.1 F)
2000-1.2 C (29.8 F)
2001-2.9 C (26.8 F)
2002-2.5 C (27.5 F)
2003-2.3 C (27.9 F)
2004-1.5 C (29.3 F)
2005-1.5 C (29.3 F)
2006-3.9 C (25.0 F)
2007-2.2 C (28.0 F)
2008-2.3 C (27.9 F)
2009-1.5 C (29.3 F)
2010-1.9 C (28.6 F)
2011-1.5 C (29.3 F)
2012-1.5 C (29.3 F)
2013-2.6 C (27.3 F)
2014-2.6 C (27.3 F)
2015-2.5 C (27.5 F)
2016-1.4 C (29.5 F)
2017-3.4 C (25.9 F)
2018-3.0 C (26.6 F)
2019-3.0 C (26.6 F)
2020-3.4 C (25.9 F)
2021-3.1 C (26.4 F)
2022-3.0 C (26.6 F)
2023-1.3 C (29.7 F)
2024-3.5 C (25.7 F)
2025-3.1 C (26.4 F)
2026-2.4 C (27.7 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Mortlake Racecourse by year The wettest day of the year at Mortlake Racecourse, 1990 to 2026. The record is 67.0 mm (2.6 in) in 2008, marked on the chart; the median year is 33.0 mm (1.3 in). 0204060801990200020102020Record: 67.0 mm (2.6 in) in 2008
The wettest day of the year at Mortlake Racecourse, 1990 to 2026. The record is 67.0 mm (2.6 in) in 2008, marked on the chart; the median year is 33.0 mm (1.3 in).
Wettest day (Rx1day) at Mortlake Racecourse by year
YearWettest day (Rx1day)
1990n/a
1991n/a
1992n/a
1993n/a
199422.0 mm (0.9 in)
199527.0 mm (1.1 in)
199624.0 mm (0.9 in)
199733.0 mm (1.3 in)
199830.0 mm (1.2 in)
199939.0 mm (1.5 in)
200037.0 mm (1.5 in)
200133.0 mm (1.3 in)
200233.0 mm (1.3 in)
200330.8 mm (1.2 in)
200438.8 mm (1.5 in)
200549.0 mm (1.9 in)
200624.2 mm (1.0 in)
200749.6 mm (2.0 in)
200867.0 mm (2.6 in)
200922.2 mm (0.9 in)
201053.4 mm (2.1 in)
201159.8 mm (2.4 in)
201219.6 mm (0.8 in)
201324.4 mm (1.0 in)
201425.2 mm (1.0 in)
201531.0 mm (1.2 in)
201633.6 mm (1.3 in)
201736.6 mm (1.4 in)
201847.4 mm (1.9 in)
201937.6 mm (1.5 in)
202034.2 mm (1.3 in)
202128.8 mm (1.1 in)
202250.0 mm (2.0 in)
202325.4 mm (1.0 in)
202431.2 mm (1.2 in)
202541.2 mm (1.6 in)
202621.8 mm (0.9 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Mortlake Racecourse by year The wettest five days of the year at Mortlake Racecourse, 1990 to 2026. The record is 123.8 mm (4.9 in) in 2011, marked on the chart; the median year is 53.4 mm (2.1 in). 2550751001251990200020102020Record: 123.8 mm (4.9 in) in 2011
The wettest five days of the year at Mortlake Racecourse, 1990 to 2026. The record is 123.8 mm (4.9 in) in 2011, marked on the chart; the median year is 53.4 mm (2.1 in).
Wettest five days (Rx5day) at Mortlake Racecourse by year
YearWettest five days (Rx5day)
1990n/a
1991n/a
1992n/a
1993n/a
199444.0 mm (1.7 in)
199552.2 mm (2.1 in)
199643.2 mm (1.7 in)
199759.4 mm (2.3 in)
199832.2 mm (1.3 in)
199945.2 mm (1.8 in)
200063.0 mm (2.5 in)
200159.2 mm (2.3 in)
200240.2 mm (1.6 in)
200353.4 mm (2.1 in)
200444.0 mm (1.7 in)
200567.6 mm (2.7 in)
200649.0 mm (1.9 in)
200767.2 mm (2.6 in)
200885.0 mm (3.3 in)
200938.4 mm (1.5 in)
201089.6 mm (3.5 in)
2011123.8 mm (4.9 in)
201232.6 mm (1.3 in)
201345.4 mm (1.8 in)
201437.2 mm (1.5 in)
201542.0 mm (1.7 in)
201659.8 mm (2.4 in)
201766.8 mm (2.6 in)
201868.2 mm (2.7 in)
201954.2 mm (2.1 in)
202075.2 mm (3.0 in)
202150.6 mm (2.0 in)
202273.4 mm (2.9 in)
202338.6 mm (1.5 in)
202437.6 mm (1.5 in)
202581.2 mm (3.2 in)
202661.0 mm (2.4 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Mortlake Racecourse by year The longest dry spell of the year at Mortlake Racecourse, 1990 to 2026. The record is 44 days in 2014, marked on the chart; the median year is 22 days. 02040601990200020102020Record: 44 days in 2014
The longest dry spell of the year at Mortlake Racecourse, 1990 to 2026. The record is 44 days in 2014, marked on the chart; the median year is 22 days.
Longest dry spell (CDD) at Mortlake Racecourse by year
YearLongest dry spell (CDD)
1990n/a
1991n/a
1992n/a
1993n/a
19943 days
199511 days
199623 days
199725 days
199822 days
199913 days
200018 days
200121 days
200223 days
200322 days
200420 days
200524 days
200636 days
200728 days
200823 days
200938 days
201016 days
201112 days
201219 days
201322 days
201444 days
201538 days
201613 days
201721 days
201818 days
201920 days
202016 days
202125 days
202232 days
202324 days
202439 days
202522 days
202642 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 Mortlake Racecourse falls on 9 October and the median first autumn frost on 14 May, which leaves a median of 224 days between them.

Fitted over all years, the growing season changes by +11.1 days per decade at this station.

Frost dates and growing season at Mortlake Racecourse
MeasureMedian, all yearsEarliest periodRecent period (1995 to 2025)Recent against earliestFitted trend
Last spring frost9 Octobern/a6 Octobern/a-2.7 days per decade
First autumn frost14 Mayn/a17 Mayn/a+8.3 days per decade
Growing days224 daysn/a227 daysn/a+11.1 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

30 years, 1996 to 2025

A day with at least 34.0 mm (1.3 in) of rain is expected about once in 2 years. A day with at least 76.5 mm (3.0 in) of rain is expected about once in 100 years.

Rainfall return levels at Mortlake Racecourse: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years34.0 mm (1.3 in)
5 years44.5 mm (1.8 in)
10 years51.8 mm (2.0 in)
25 years61.4 mm (2.4 in)
50 years68.9 mm (2.7 in)Longer than the 30 years of record
100 years76.5 mm (3.0 in)Longer than the 30 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, 30 years of values from 1996 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: 67.0 mm (2.6 in) in 2008; 59.8 mm (2.4 in) in 2011; 53.4 mm (2.1 in) in 2010.

Download the Data

  • Data for Mortlake Racecourse standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Mortlake Racecourse 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 . Last revised (2026-10-13).