Built 2026-10-17 (17 October 2026)

Rock Is L&D 15 Weather Records (USC00117391)

Record envelope, standing records and threshold days for Rock Is L&D 15 (USC00117391), Illinois, United States, with 161 years of record.

Key Facts for Rock Is L&D 15

  • Rock Is L&D 15 (USC00117391) is a weather station in Illinois, United States at 41.52 latitude and -90.56 longitude, 173 m (568 ft) above sea level.
  • The station reports from 1866 to 2026, 161 years of record.
  • 1,464 records set at Rock Is L&D 15 still stand.
  • Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Rock Is L&D 15 set a daily record high maximum temperature of 32.8 C (91.0 F) on 12 October 2026 (provisional).

Provisional Records

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

About the Station

  • Location: Illinois, United States, 41.52 latitude, -90.56 longitude.
  • Elevation: 173 m (568 ft).
  • Period of record: 1866 to 2026, 161 years.
  • Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

21 days at or beyond a record
Daily record high and record low at Rock Is L&D 15, with 2026 drawn through them The band shows the record high and record low for each calendar day at Rock Is L&D 15. The lines show the 2026 daily maximum and minimum. 21 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 Rock Is L&D 15. The lines show the 2026 daily maximum and minimum. 21 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Rock Is L&D 15, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan20.6 C (69.1 F)-35.6 C (-32.1 F)15.0 C (59.0 F)-24.4 C (-11.9 F)
Feb24.4 C (75.9 F)-30.0 C (-22.0 F)20.0 C (68.0 F)-16.7 C (1.9 F)
Mar31.1 C (88.0 F)-25.6 C (-14.1 F)28.9 C (84.0 F)-13.9 C (7.0 F)
Apr33.9 C (93.0 F)-8.9 C (16.0 F)30.0 C (86.0 F)0.6 C (33.1 F)
May35.6 C (96.1 F)-4.4 C (24.1 F)35.0 C (95.0 F)-1.7 C (28.9 F)
Jun37.8 C (100.0 F)2.2 C (36.0 F)37.2 C (99.0 F)8.9 C (48.0 F)
Jul40.0 C (104.0 F)3.3 C (37.9 F)37.2 C (99.0 F)15.6 C (60.1 F)
Aug39.4 C (102.9 F)6.1 C (43.0 F)35.6 C (96.1 F)16.1 C (61.0 F)
Sep36.7 C (98.1 F)0.0 C (32.0 F)36.7 C (98.1 F)11.7 C (53.1 F)
Oct35.0 C (95.0 F)-11.1 C (12.0 F)32.8 C (91.0 F)10.0 C (50.0 F)
Nov26.7 C (80.1 F)-23.9 C (-11.0 F)n/an/a
Dec22.2 C (72.0 F)-32.2 C (-26.0 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Rock Is L&D 15 by the year they were set 1,464 records at Rock Is L&D 15 still stand. 1890 holds the most, with 72. 0204060801872: 311873: 641874: 571875: 681876: 411877: 51880: 101888: 11889: 301890: 721891: 411892: 31985: 211986: 151987: 21988: 341989: 451990: 311991: 481992: 351993: 141994: 251995: 191996: 331997: 231998: 371999: 212000: 422001: 242002: 262003: 162004: 242005: 302006: 312007: 162008: 142009: 222010: 72011: 222012: 352013: 192014: 292015: 212016: 112017: 422018: 202019: 332020: 172021: 252022: 232023: 162024: 242025: 222026: 27187218801985199119972003200920152021
1,464 records at Rock Is L&D 15 still stand. 1890 holds the most, with 72.
Standing records at Rock Is L&D 15 by the year they were set
Year setStanding records
187231
187364
187457
187568
187641
18775
188010
18881
188930
189072
189141
18923
198521
198615
19872
198834
198945
199031
199148
199235
199314
199425
199519
199633
199723
199837
199921
200042
200124
200226
200316
200424
200530
200631
200716
200814
200922
20107
201122
201235
201319
201429
201521
201611
201742
201820
201933
202017
202125
202223
202316
202424
202522
202627

All-Time Record Progression

3 new records
When Rock Is L&D 15 set new all-time records 3 all-time records were set at Rock Is L&D 15 between 31 January 2019 and 18 January 2024. Each dot is a new record. Record low minimum temperatureRecord snow depth31 January 2019: Record low minimum temperature -35.6 C (-32.1 F)14 January 2024: Record snow depth 40.6 cm (16.0 in)18 January 2024: Record snow depth 45.7 cm (18.0 in)20202025
3 all-time records were set at Rock Is L&D 15 between 31 January 2019 and 18 January 2024. Each dot is a new record.
When Rock Is L&D 15 set new all-time records
DateKindDetail
2019-01-31Record low minimum temperatureRecord low minimum temperature -35.6 C (-32.1 F)
2024-01-14Record snow depthRecord snow depth 40.6 cm (16.0 in)
2024-01-18Record snow depthRecord snow depth 45.7 cm (18.0 in)

Wettest Day of Each Month

Jun: 166.6 mm (6.6 in)
Record daily precipitation for each month at Rock Is L&D 15 The wettest day on record for each calendar month at Rock Is L&D 15. The most was 166.6 mm (6.6 in) on 17 June 1990. 050100150200 Jan: 49.5 mm (1.9 in), 29 January 2006 Jan Feb: 98.6 mm (3.9 in), 24 February 1870 Feb Mar: 134.6 mm (5.3 in), 12 March 1870 Mar Apr: 58.4 mm (2.3 in), 26 April 2009 Apr May: 92.5 mm (3.6 in), 26 May 2013 May Jun: 166.6 mm (6.6 in), 17 June 1990 Jun Jul: 131.1 mm (5.2 in), 13 July 1889 Jul Aug: 101.6 mm (4.0 in), 23 August 1996 Aug Sep: 101.6 mm (4.0 in), 18 September 1874 Sep Oct: 81.3 mm (3.2 in), 18 October 1998 Oct Nov: 117.9 mm (4.6 in), 19 November 1869 Nov Dec: 95.5 mm (3.8 in), 21 December 1871 Dec
The wettest day on record for each calendar month at Rock Is L&D 15. The most was 166.6 mm (6.6 in) on 17 June 1990.
Record daily precipitation for each month at Rock Is L&D 15
MonthRecord daily precipitation (mm)Date
Jan49.5 mm (1.9 in)29 January 2006
Feb98.6 mm (3.9 in)24 February 1870
Mar134.6 mm (5.3 in)12 March 1870
Apr58.4 mm (2.3 in)26 April 2009
May92.5 mm (3.6 in)26 May 2013
Jun166.6 mm (6.6 in)17 June 1990
Jul131.1 mm (5.2 in)13 July 1889
Aug101.6 mm (4.0 in)23 August 1996
Sep101.6 mm (4.0 in)18 September 1874
Oct81.3 mm (3.2 in)18 October 1998
Nov117.9 mm (4.6 in)19 November 1869
Dec95.5 mm (3.8 in)21 December 1871

Period of Record Coverage

1872 to 2026
Days with data per year at Rock Is L&D 15 54 years of record at Rock Is L&D 15, 1872 to 2026. 12 years have data for under 90 percent of days and are left out of rankings: 1872, 1877, 1880, 1888, 1891, 1892, 1985, 1986 and others. 1872: 259 of 366 days1873: 358 of 365 days1874: 357 of 365 days1875: 349 of 365 days1876: 350 of 366 days1877: 31 of 365 days1880: 92 of 366 days1888: 31 of 366 days1889: 365 of 365 days1890: 362 of 365 days1891: 287 of 365 days1892: 51 of 366 days1985: 182 of 365 days1986: 210 of 365 days1987: 30 of 365 days1988: 326 of 366 days1989: 363 of 365 days1990: 361 of 365 days1991: 362 of 365 days1992: 362 of 366 days1993: 361 of 365 days1994: 363 of 365 days1995: 360 of 365 days1996: 360 of 366 days1997: 364 of 365 days1998: 361 of 365 days1999: 364 of 365 days2000: 362 of 366 days2001: 359 of 365 days2002: 362 of 365 days2003: 363 of 365 days2004: 331 of 366 days2005: 361 of 365 days2006: 357 of 365 days2007: 363 of 365 days2008: 358 of 366 days2009: 355 of 365 days2010: 356 of 365 days2011: 317 of 365 days2012: 364 of 366 days2013: 359 of 365 days2014: 356 of 365 days2015: 355 of 365 days2016: 360 of 366 days2017: 363 of 365 days2018: 358 of 365 days2019: 361 of 365 days2020: 355 of 366 days2021: 364 of 365 days2022: 363 of 365 days2023: 364 of 365 days2024: 353 of 366 days2025: 330 of 365 days2026: 277 of 365 days188018901990200020102020
54 years of record at Rock Is L&D 15, 1872 to 2026. 12 years have data for under 90 percent of days and are left out of rankings: 1872, 1877, 1880, 1888, 1891, 1892, 1985, 1986 and others.
Days with data per year at Rock Is L&D 15
YearDays with dataShare of yearComplete
187225971%No
187335898%Yes
187435798%Yes
187534996%Yes
187635096%Yes
1877318%No
18809225%No
1888318%No
1889365100%Yes
189036299%Yes
189128779%No
18925114%No
198518250%No
198621058%No
1987308%No
198832689%No
198936399%Yes
199036199%Yes
199136299%Yes
199236299%Yes
199336199%Yes
199436399%Yes
199536099%Yes
199636098%Yes
1997364100%Yes
199836199%Yes
1999364100%Yes
200036299%Yes
200135998%Yes
200236299%Yes
200336399%Yes
200433190%Yes
200536199%Yes
200635798%Yes
200736399%Yes
200835898%Yes
200935597%Yes
201035698%Yes
201131787%No
201236499%Yes
201335998%Yes
201435698%Yes
201535597%Yes
201636098%Yes
201736399%Yes
201835898%Yes
201936199%Yes
202035597%Yes
2021364100%Yes
202236399%Yes
2023364100%Yes
202435396%Yes
202533090%Yes
202627776%No

Latest Records

20
Latest records at Rock Is L&D 15
DateStationRecordValueBeat old record byOld record stoodSignificance
12 October 2026Rock Is L&D 15, USdaily high max (Provisional)32.8 C (91.0 F)3.4 C (6.1 F)31 years24 of 100 (Routine)
12 October 2026Rock Is L&D 15, USdaily high min (Tie, Provisional)20.6 C (69.1 F)tie28 years4 of 100 (Routine)
10 October 2026Rock Is L&D 15, USdaily high max (Provisional)28.9 C (84.0 F)1.1 C (2.0 F)15 years15 of 100 (Routine)
1 October 2026Rock Is L&D 15, USdaily rain (Provisional)67.1 mm (2.6 in)50.1 mm (2.0 in)31 years59 of 100 (Notable)
30 September 2026Rock Is L&D 15, USdaily rain (Provisional)43.2 mm (1.7 in)17.8 mm (0.7 in)150 years52 of 100 (Notable)
19 September 2026Rock Is L&D 15, USdaily rain (Provisional)51.8 mm (2.0 in)12.4 mm (0.5 in)24 years25 of 100 (Routine)
8 September 2026Rock Is L&D 15, USdaily high max (Tie, Provisional)35.0 C (95.0 F)tie40 years5 of 100 (Routine)
5 September 2026Rock Is L&D 15, USdaily high min (Provisional)25.0 C (77.0 F)0.6 C (1.1 F)11 years14 of 100 (Routine)
4 September 2026Rock Is L&D 15, USmonthly high min (Provisional)26.7 C (80.1 F)0.6 C (1.1 F)15 years25 of 100 (Routine)
4 September 2026Rock Is L&D 15, USdaily high max (Provisional)35.0 C (95.0 F)1.1 C (2.0 F)36 years22 of 100 (Routine)
3 September 2026Rock Is L&D 15, USdaily high max (Provisional)35.6 C (96.1 F)1.2 C (2.2 F)3 years12 of 100 (Routine)
3 September 2026Rock Is L&D 15, USmonthly high min (Tie, Provisional)26.1 C (79.0 F)tie15 years6 of 100 (Routine)
1 September 2026Rock Is L&D 15, USdaily high min (Provisional)25.0 C (77.0 F)1.1 C (2.0 F)25 years19 of 100 (Routine)
1 September 2026Rock Is L&D 15, USmonthly high max (Tie, Provisional)36.7 C (98.1 F)tie40 years8 of 100 (Routine)
31 July 2026Rock Is L&D 15, USdaily rain35.6 mm (1.4 in)10.2 mm (0.4 in)150 years46 of 100 (Notable)
27 July 2026Rock Is L&D 15, USdaily high min26.1 C (79.0 F)1.7 C (3.1 F)27 years22 of 100 (Routine)
17 July 2026Rock Is L&D 15, USdaily high min25.6 C (78.1 F)0.6 C (1.1 F)20 years17 of 100 (Routine)
16 July 2026Rock Is L&D 15, USdaily high min25.6 C (78.1 F)0.6 C (1.1 F)20 years17 of 100 (Routine)
2 July 2026Rock Is L&D 15, USdaily high max37.2 C (99.0 F)2.8 C (5.0 F)13 years21 of 100 (Routine)
1 July 2026Rock Is L&D 15, USdaily high max36.7 C (98.1 F)2.8 C (5.0 F)35 years27 of 100 (Routine)

Climate Trend

39 complete years, 1873 to 2024
Annual mean temperature at Rock Is L&D 15 as warming stripes, 1873 to 2024 One stripe for each of 39 complete years at Rock Is L&D 15, 1873 to 2024. Blue stripes are years cooler than the station's own mean of 10.8 C (51.4 F); red stripes are warmer. The coolest year was 1875, at 7.3 C (45.1 F), and the warmest was 2024, at 12.9 C (55.3 F). The strongest colour marks a difference of 3.6 C (6.5 F). 1873: 8.4 C, -2.4 C from the station mean1874: 9.4 C, -1.3 C from the station mean1875: 7.3 C, -3.5 C from the station mean1876: 9.0 C, -1.8 C from the station mean1889: 10.1 C, -0.7 C from the station mean1890: 9.8 C, -1.0 C from the station mean1989: 9.8 C, -0.9 C from the station mean1990: 11.6 C, +0.8 C from the station mean1991: 11.5 C, +0.7 C from the station mean1992: 10.5 C, -0.3 C from the station mean1993: 10.1 C, -0.7 C from the station mean1994: 11.0 C, +0.3 C from the station mean1995: 10.5 C, -0.3 C from the station mean1996: 9.6 C, -1.1 C from the station mean1997: 10.5 C, -0.3 C from the station mean1998: 12.7 C, +2.0 C from the station mean1999: 12.2 C, +1.4 C from the station mean2000: 11.4 C, +0.6 C from the station mean2001: 11.8 C, +1.1 C from the station mean2002: 11.8 C, +1.0 C from the station mean2003: 11.0 C, +0.3 C from the station mean2005: 12.2 C, +1.4 C from the station mean2006: 12.4 C, +1.6 C from the station mean2007: 11.3 C, +0.6 C from the station mean2008: 9.9 C, -0.8 C from the station mean2009: 9.7 C, -1.1 C from the station mean2012: 12.7 C, +1.9 C from the station mean2013: 9.8 C, -0.9 C from the station mean2014: 8.9 C, -1.9 C from the station mean2015: 10.9 C, +0.1 C from the station mean2016: 12.0 C, +1.2 C from the station mean2017: 11.4 C, +0.6 C from the station mean2018: 10.5 C, -0.3 C from the station mean2019: 9.4 C, -1.4 C from the station mean2020: 11.1 C, +0.4 C from the station mean2021: 11.8 C, +1.1 C from the station mean2022: 10.7 C, -0.1 C from the station mean2023: 12.5 C, +1.8 C from the station mean2024: 12.9 C, +2.2 C from the station mean1873188018901900191019201930194019501960197019801990200020102020
One stripe for each of 39 complete years at Rock Is L&D 15, 1873 to 2024. Blue stripes are years cooler than the station's own mean of 10.8 C (51.4 F); red stripes are warmer. The coolest year was 1875, at 7.3 C (45.1 F), and the warmest was 2024, at 12.9 C (55.3 F). The strongest colour marks a difference of 3.6 C (6.5 F).
Annual mean temperature at Rock Is L&D 15 as warming stripes, 1873 to 2024
YearAnnual mean temperatureDifference from the station mean
18738.4 C-2.42 C
18749.4 C-1.33 C
18757.3 C-3.52 C
18769.0 C-1.77 C
188910.1 C-0.72 C
18909.8 C-1.02 C
19899.8 C-0.95 C
199011.6 C+0.82 C
199111.5 C+0.73 C
199210.5 C-0.27 C
199310.1 C-0.68 C
199411.0 C+0.27 C
199510.5 C-0.29 C
19969.6 C-1.13 C
199710.5 C-0.32 C
199812.7 C+1.97 C
199912.2 C+1.41 C
200011.4 C+0.58 C
200111.8 C+1.05 C
200211.8 C+1.03 C
200311.0 C+0.25 C
200512.2 C+1.39 C
200612.4 C+1.59 C
200711.3 C+0.57 C
20089.9 C-0.84 C
20099.7 C-1.11 C
201212.7 C+1.91 C
20139.8 C-0.93 C
20148.9 C-1.86 C
201510.9 C+0.09 C
201612.0 C+1.19 C
201711.4 C+0.63 C
201810.5 C-0.27 C
20199.4 C-1.40 C
202011.1 C+0.35 C
202111.8 C+1.05 C
202210.7 C-0.12 C
202312.5 C+1.75 C
202412.9 C+2.16 C

The annual mean temperature here has risen by 0.2 C (0.1 to 0.2) per decade over 1873 to 2024. In Fahrenheit: 0.3 F (0.2 to 0.4) per decade. The slope is a straight line fitted to 39 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Rock Is L&D 15
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.2 C (0.1 to 0.2) per decade0.3 F (0.2 to 0.4) per decade1873 to 202439Rise
Mean daily maximum0.07 C (-0.01 to 0.15) per decade0.12 F (-0.02 to 0.26) per decade1873 to 202439Not clearly different from zero
Mean daily minimum0.3 C (0.2 to 0.3) per decade0.5 F (0.3 to 0.6) per decade1873 to 202439Rise

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

1866 to 2026
Yearly extremes at Rock Is L&D 15: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)40.0 C (104.0 F)187435.7 C (96.3 F)54
Coldest night (TNn)-35.6 C (-32.1 F)2019-23.6 C (-10.5 F)54
Wettest day (Rx1day)166.6 mm (6.6 in)199065.8 mm (2.6 in)60
Wettest five days (Rx5day)255.3 mm (10.1 in)187092.9 mm (3.7 in)60
Longest dry spell (CDD)45 days202621 days60

Hottest day (TXx)

Hottest day (TXx) at Rock Is L&D 15 by year The hottest day of the year at Rock Is L&D 15, 1866 to 2026. The record is 40.0 C (104.0 F) in 1874, marked on the chart; the median year is 35.7 C (96.3 F). 1020304018801900192019401960198020002020Record: 40.0 C (104.0 F) in 1874
The hottest day of the year at Rock Is L&D 15, 1866 to 2026. The record is 40.0 C (104.0 F) in 1874, marked on the chart; the median year is 35.7 C (96.3 F).
Hottest day (TXx) at Rock Is L&D 15 by year
YearHottest day (TXx)
1866n/a
1867n/a
1868n/a
1869n/a
1870n/a
1871n/a
187236.9 C (98.4 F)
187338.9 C (102.0 F)
187440.0 C (104.0 F)
187535.3 C (95.5 F)
187635.8 C (96.4 F)
187713.9 C (57.0 F)
188035.0 C (95.0 F)
188816.7 C (62.1 F)
188933.3 C (91.9 F)
189038.6 C (101.5 F)
189132.8 C (91.0 F)
189210.6 C (51.1 F)
198536.7 C (98.1 F)
198635.0 C (95.0 F)
198724.4 C (75.9 F)
198838.3 C (100.9 F)
198936.1 C (97.0 F)
199036.7 C (98.1 F)
199136.7 C (98.1 F)
199233.3 C (91.9 F)
199335.0 C (95.0 F)
199435.0 C (95.0 F)
199537.2 C (99.0 F)
199634.4 C (93.9 F)
199735.6 C (96.1 F)
199836.1 C (97.0 F)
199936.7 C (98.1 F)
200036.1 C (97.0 F)
200135.0 C (95.0 F)
200234.4 C (93.9 F)
200336.1 C (97.0 F)
200433.3 C (91.9 F)
200537.2 C (99.0 F)
200639.4 C (102.9 F)
200733.3 C (91.9 F)
200833.3 C (91.9 F)
200934.4 C (93.9 F)
201035.0 C (95.0 F)
201136.1 C (97.0 F)
201238.9 C (102.0 F)
201336.7 C (98.1 F)
201432.8 C (91.0 F)
201536.7 C (98.1 F)
201633.9 C (93.0 F)
201734.4 C (93.9 F)
201835.0 C (95.0 F)
201936.1 C (97.0 F)
202034.4 C (93.9 F)
202137.2 C (99.0 F)
202237.8 C (100.0 F)
202336.1 C (97.0 F)
202435.6 C (96.1 F)
202537.2 C (99.0 F)
202637.2 C (99.0 F)

Coldest night (TNn)

Coldest night (TNn) at Rock Is L&D 15 by year The coldest night of the year at Rock Is L&D 15, 1866 to 2026. The record is -35.6 C (-32.1 F) in 2019, marked on the chart; the median year is -23.6 C (-10.5 F). -40-30-20-1001018801900192019401960198020002020Record: -35.6 C (-32.1 F) in 2019
The coldest night of the year at Rock Is L&D 15, 1866 to 2026. The record is -35.6 C (-32.1 F) in 2019, marked on the chart; the median year is -23.6 C (-10.5 F).
Coldest night (TNn) at Rock Is L&D 15 by year
YearColdest night (TNn)
1866n/a
1867n/a
1868n/a
1869n/a
1870n/a
1871n/a
1872-32.2 C (-26.0 F)
1873-33.9 C (-29.0 F)
1874-25.0 C (-13.0 F)
1875-30.6 C (-23.1 F)
1876-28.9 C (-20.0 F)
1877-27.8 C (-18.0 F)
18801.7 C (35.1 F)
1888-11.1 C (12.0 F)
1889-23.9 C (-11.0 F)
1890-23.9 C (-11.0 F)
1891-23.9 C (-11.0 F)
1892-24.4 C (-11.9 F)
1985-23.9 C (-11.0 F)
1986-22.8 C (-9.0 F)
1987-6.7 C (19.9 F)
1988-23.9 C (-11.0 F)
1989-27.8 C (-18.0 F)
1990-21.1 C (-6.0 F)
1991-20.6 C (-5.1 F)
1992-20.6 C (-5.1 F)
1993-20.0 C (-4.0 F)
1994-27.2 C (-17.0 F)
1995-21.1 C (-6.0 F)
1996-30.0 C (-22.0 F)
1997-22.8 C (-9.0 F)
1998-18.3 C (-0.9 F)
1999-26.1 C (-15.0 F)
2000-23.9 C (-11.0 F)
2001-20.0 C (-4.0 F)
2002-19.4 C (-2.9 F)
2003-22.2 C (-8.0 F)
2004-22.8 C (-9.0 F)
2005-20.0 C (-4.0 F)
2006-22.2 C (-8.0 F)
2007-21.7 C (-7.1 F)
2008-23.9 C (-11.0 F)
2009-27.8 C (-18.0 F)
2010-21.7 C (-7.1 F)
2011-22.8 C (-9.0 F)
2012-16.1 C (3.0 F)
2013-20.6 C (-5.1 F)
2014-26.1 C (-15.0 F)
2015-23.3 C (-9.9 F)
2016-23.3 C (-9.9 F)
2017-24.4 C (-11.9 F)
2018-26.7 C (-16.1 F)
2019-35.6 C (-32.1 F)
2020-19.4 C (-2.9 F)
2021-26.1 C (-15.0 F)
2022-22.2 C (-8.0 F)
2023-19.4 C (-2.9 F)
2024-26.1 C (-15.0 F)
2025-23.9 C (-11.0 F)
2026-24.4 C (-11.9 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Rock Is L&D 15 by year The wettest day of the year at Rock Is L&D 15, 1866 to 2026. The record is 166.6 mm (6.6 in) in 1990, marked on the chart; the median year is 65.8 mm (2.6 in). 05010015020018801900192019401960198020002020Record: 166.6 mm (6.6 in) in 1990
The wettest day of the year at Rock Is L&D 15, 1866 to 2026. The record is 166.6 mm (6.6 in) in 1990, marked on the chart; the median year is 65.8 mm (2.6 in).
Wettest day (Rx1day) at Rock Is L&D 15 by year
YearWettest day (Rx1day)
186668.6 mm (2.7 in)
186758.7 mm (2.3 in)
186857.2 mm (2.3 in)
1869117.9 mm (4.6 in)
1870134.6 mm (5.3 in)
187195.5 mm (3.8 in)
187255.9 mm (2.2 in)
187333.5 mm (1.3 in)
1874101.6 mm (4.0 in)
187557.2 mm (2.3 in)
187681.3 mm (3.2 in)
187712.7 mm (0.5 in)
188095.0 mm (3.7 in)
188823.4 mm (0.9 in)
1889131.1 mm (5.2 in)
189055.9 mm (2.2 in)
189149.8 mm (2.0 in)
189223.9 mm (0.9 in)
198564.8 mm (2.6 in)
198661.0 mm (2.4 in)
198717.8 mm (0.7 in)
198854.4 mm (2.1 in)
198960.7 mm (2.4 in)
1990166.6 mm (6.6 in)
199193.7 mm (3.7 in)
199275.2 mm (3.0 in)
199360.5 mm (2.4 in)
199442.9 mm (1.7 in)
199552.1 mm (2.1 in)
1996101.6 mm (4.0 in)
199751.3 mm (2.0 in)
199881.3 mm (3.2 in)
199973.9 mm (2.9 in)
200052.1 mm (2.1 in)
200173.7 mm (2.9 in)
200285.1 mm (3.4 in)
200364.8 mm (2.6 in)
200451.1 mm (2.0 in)
200547.0 mm (1.9 in)
200676.5 mm (3.0 in)
200796.8 mm (3.8 in)
2008109.2 mm (4.3 in)
200958.4 mm (2.3 in)
201047.0 mm (1.9 in)
201154.9 mm (2.2 in)
201277.5 mm (3.1 in)
201392.5 mm (3.6 in)
2014121.2 mm (4.8 in)
201583.6 mm (3.3 in)
201673.7 mm (2.9 in)
201774.9 mm (2.9 in)
201894.0 mm (3.7 in)
201948.3 mm (1.9 in)
202071.4 mm (2.8 in)
202158.4 mm (2.3 in)
202251.6 mm (2.0 in)
202343.4 mm (1.7 in)
202466.8 mm (2.6 in)
202575.7 mm (3.0 in)
202667.1 mm (2.6 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Rock Is L&D 15 by year The wettest five days of the year at Rock Is L&D 15, 1866 to 2026. The record is 255.3 mm (10.1 in) in 1870, marked on the chart; the median year is 92.9 mm (3.7 in). 010020030018801900192019401960198020002020Record: 255.3 mm (10.1 in) in 1870
The wettest five days of the year at Rock Is L&D 15, 1866 to 2026. The record is 255.3 mm (10.1 in) in 1870, marked on the chart; the median year is 92.9 mm (3.7 in).
Wettest five days (Rx5day) at Rock Is L&D 15 by year
YearWettest five days (Rx5day)
186680.3 mm (3.2 in)
186775.5 mm (3.0 in)
1868123.2 mm (4.9 in)
1869163.6 mm (6.4 in)
1870255.3 mm (10.1 in)
1871137.7 mm (5.4 in)
187288.9 mm (3.5 in)
187349.5 mm (1.9 in)
1874108.0 mm (4.3 in)
187585.1 mm (3.4 in)
187685.1 mm (3.4 in)
187717.8 mm (0.7 in)
1880139.2 mm (5.5 in)
188824.9 mm (1.0 in)
1889172.2 mm (6.8 in)
189077.2 mm (3.0 in)
189156.9 mm (2.2 in)
189223.9 mm (0.9 in)
198596.8 mm (3.8 in)
198696.6 mm (3.8 in)
198732.1 mm (1.3 in)
198856.9 mm (2.2 in)
198971.6 mm (2.8 in)
1990192.2 mm (7.6 in)
199193.7 mm (3.7 in)
1992107.7 mm (4.2 in)
199376.8 mm (3.0 in)
199449.8 mm (2.0 in)
199573.6 mm (2.9 in)
1996107.5 mm (4.2 in)
199789.7 mm (3.5 in)
1998112.1 mm (4.4 in)
1999101.6 mm (4.0 in)
200096.8 mm (3.8 in)
200189.0 mm (3.5 in)
2002131.3 mm (5.2 in)
200390.7 mm (3.6 in)
200480.3 mm (3.2 in)
200578.8 mm (3.1 in)
200692.0 mm (3.6 in)
200796.8 mm (3.8 in)
2008139.8 mm (5.5 in)
200996.5 mm (3.8 in)
201085.3 mm (3.4 in)
201170.4 mm (2.8 in)
201277.8 mm (3.1 in)
2013183.7 mm (7.2 in)
2014122.2 mm (4.8 in)
2015133.7 mm (5.3 in)
2016125.2 mm (4.9 in)
2017115.1 mm (4.5 in)
2018108.2 mm (4.3 in)
2019107.3 mm (4.2 in)
2020106.9 mm (4.2 in)
202188.6 mm (3.5 in)
202266.3 mm (2.6 in)
202370.1 mm (2.8 in)
202488.7 mm (3.5 in)
2025107.2 mm (4.2 in)
2026122.9 mm (4.8 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Rock Is L&D 15 by year The longest dry spell of the year at Rock Is L&D 15, 1866 to 2026. The record is 45 days in 2026, marked on the chart; the median year is 21 days. 102030405018801900192019401960198020002020Record: 45 days in 2026
The longest dry spell of the year at Rock Is L&D 15, 1866 to 2026. The record is 45 days in 2026, marked on the chart; the median year is 21 days.
Longest dry spell (CDD) at Rock Is L&D 15 by year
YearLongest dry spell (CDD)
186619 days
186718 days
186821 days
186935 days
187028 days
187120 days
187223 days
187329 days
187415 days
187520 days
187615 days
187714 days
188014 days
188813 days
188921 days
189020 days
189122 days
189221 days
198517 days
198629 days
198713 days
198841 days
198919 days
199016 days
199133 days
199216 days
199327 days
199422 days
199529 days
199623 days
199714 days
199823 days
199937 days
200018 days
200119 days
200222 days
200321 days
200420 days
200516 days
200620 days
200727 days
200823 days
200927 days
201027 days
201117 days
201224 days
201340 days
201420 days
201520 days
201622 days
201728 days
201822 days
201919 days
202021 days
202127 days
202227 days
202327 days
202423 days
202519 days
202645 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

39 years with a frost

Across 39 years with a frost, the median last spring frost at Rock Is L&D 15 falls on 12 April and the median first autumn frost on 23 October, which leaves a median of 188 days between them.

Fitted over all years, the growing season changes by +2.2 days per decade at this station.

Frost dates and growing season at Rock Is L&D 15
MeasureMedian, all yearsEarliest periodRecent period (1992 to 2024)Recent against earliestFitted trend
Last spring frost12 Apriln/a12 Apriln/a-1.1 days per decade
First autumn frost23 Octobern/a28 Octobern/a+1.2 days per decade
Growing days188 daysn/a199 daysn/a+2.2 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

51 years, 1867 to 2025

A day with at least 68.2 mm (2.7 in) of rain is expected about once in 2 years. A day with at least 175.1 mm (6.9 in) of rain is expected about once in 100 years.

Rainfall return levels at Rock Is L&D 15: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years68.2 mm (2.7 in)
5 years91.9 mm (3.6 in)
10 years109.4 mm (4.3 in)
25 years133.8 mm (5.3 in)
50 years153.7 mm (6.1 in)
100 years175.1 mm (6.9 in)Longer than the 51 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, 51 years of values from 1867 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: 166.6 mm (6.6 in) in 1990; 134.6 mm (5.3 in) in 1870; 131.1 mm (5.2 in) in 1889.

Download the Data

  • Data for Rock Is L&D 15 standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Rock Is L&D 15 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.

Data as of . Last revised (2026-10-16).