Built 2026-10-16 (16 October 2026)

Rockford Weather Records (USC00117375)

Record envelope, standing records and threshold days for Rockford (USC00117375), Illinois, United States, with 65 years of record.

Key Facts for Rockford

  • Rockford (USC00117375) is a weather station in Illinois, United States at 42.28 latitude and -89.08 longitude, 226 m (741 ft) above sea level.
  • The station reports from 1893 to 1957, 65 years of record.
  • 1,464 records set at Rockford still stand.
  • Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Rockford set a daily record low maximum temperature of 9.4 C (48.9 F) on 19 May 1957.

About the Station

  • Location: Illinois, United States, 42.28 latitude, -89.08 longitude.
  • Elevation: 226 m (741 ft).
  • Period of record: 1893 to 1957, 65 years.
  • Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

0 days at or beyond a record
Daily record high and record low at Rockford, with 2026 drawn through them The band shows the record high and record low for each calendar day at Rockford. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -40-200204060 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Rockford. 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 Rockford, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan16.1 C (61.0 F)-31.7 C (-25.1 F)n/an/a
Feb19.4 C (66.9 F)-31.7 C (-25.1 F)n/an/a
Mar27.8 C (82.0 F)-22.8 C (-9.0 F)n/an/a
Apr33.9 C (93.0 F)-10.0 C (14.0 F)n/an/a
May41.1 C (106.0 F)-2.8 C (27.0 F)n/an/a
Jun41.1 C (106.0 F)1.7 C (35.1 F)n/an/a
Jul44.4 C (111.9 F)6.1 C (43.0 F)n/an/a
Aug40.0 C (104.0 F)1.7 C (35.1 F)n/an/a
Sep39.4 C (102.9 F)-4.4 C (24.1 F)n/an/a
Oct32.8 C (91.0 F)-13.9 C (7.0 F)n/an/a
Nov27.2 C (81.0 F)-22.2 C (-8.0 F)n/an/a
Dec17.8 C (64.0 F)-30.6 C (-23.1 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Rockford by the year they were set 1,464 records at Rockford still stand. 1896 holds the most, with 50. 02040601893: 201895: 351896: 501897: 351898: 131903: 151904: 81905: 171906: 201907: 291908: 261909: 391910: 241911: 261912: 411913: 321914: 241915: 331916: 271917: 371918: 311919: 171920: 321921: 261922: 191923: 221924: 381925: 351926: 211927: 191928: 251929: 191930: 461931: 351932: 271933: 261934: 381935: 201936: 461937: 191938: 231939: 171940: 191941: 201942: 201943: 111944: 221945: 271946: 61947: 181948: 141949: 221950: 181951: 311952: 191953: 201954: 91955: 91956: 201957: 71893190419101916192219281934194019461952
1,464 records at Rockford still stand. 1896 holds the most, with 50.
Standing records at Rockford by the year they were set
Year setStanding records
189320
189535
189650
189735
189813
190315
19048
190517
190620
190729
190826
190939
191024
191126
191241
191332
191424
191533
191627
191737
191831
191917
192032
192126
192219
192322
192438
192535
192621
192719
192825
192919
193046
193135
193227
193326
193438
193520
193646
193719
193823
193917
194019
194120
194220
194311
194422
194527
19466
194718
194814
194922
195018
195131
195219
195320
19549
19559
195620
19577

All-Time Record Progression

8 new records
When Rockford set new all-time records 8 all-time records were set at Rockford between 31 May 1934 and 18 July 1952. Each dot is a new record. Record high maximum temperatureRecord daily precipitation31 May 1934: Record high maximum temperature 41.1 C (106.0 F)24 July 1934: Record high maximum temperature 41.7 C (107.1 F)11 July 1936: Record high maximum temperature 42.2 C (108.0 F)12 July 1936: Record high maximum temperature 42.8 C (109.0 F)13 July 1936: Record high maximum temperature 43.3 C (109.9 F)14 July 1936: Record high maximum temperature 44.4 C (111.9 F)9 September 1941: Record daily precipitation 138.4 mm (5.4 in)18 July 1952: Record daily precipitation 213.6 mm (8.4 in)1935194019451950
8 all-time records were set at Rockford between 31 May 1934 and 18 July 1952. Each dot is a new record.
When Rockford set new all-time records
DateKindDetail
1934-05-31Record high maximum temperatureRecord high maximum temperature 41.1 C (106.0 F)
1934-07-24Record high maximum temperatureRecord high maximum temperature 41.7 C (107.1 F)
1936-07-11Record high maximum temperatureRecord high maximum temperature 42.2 C (108.0 F)
1936-07-12Record high maximum temperatureRecord high maximum temperature 42.8 C (109.0 F)
1936-07-13Record high maximum temperatureRecord high maximum temperature 43.3 C (109.9 F)
1936-07-14Record high maximum temperatureRecord high maximum temperature 44.4 C (111.9 F)
1941-09-09Record daily precipitationRecord daily precipitation 138.4 mm (5.4 in)
1952-07-18Record daily precipitationRecord daily precipitation 213.6 mm (8.4 in)

Wettest Day of Each Month

Jul: 213.6 mm (8.4 in)
Record daily precipitation for each month at Rockford The wettest day on record for each calendar month at Rockford. The most was 213.6 mm (8.4 in) on 18 July 1952. 0100200300 Jan: 50.8 mm (2.0 in), 24 January 1938 Jan Feb: 33.8 mm (1.3 in), 25 February 1926 Feb Mar: 51.1 mm (2.0 in), 25 March 1920 Mar Apr: 64.3 mm (2.5 in), 30 April 1911 Apr May: 70.6 mm (2.8 in), 27 May 1909 May Jun: 118.6 mm (4.7 in), 14 June 1926 Jun Jul: 213.6 mm (8.4 in), 18 July 1952 Jul Aug: 114.3 mm (4.5 in), 2 August 1942 Aug Sep: 138.4 mm (5.4 in), 9 September 1941 Sep Oct: 111.3 mm (4.4 in), 10 October 1954 Oct Nov: 68.6 mm (2.7 in), 17 November 1928 Nov Dec: 59.2 mm (2.3 in), 30 December 1936 Dec
The wettest day on record for each calendar month at Rockford. The most was 213.6 mm (8.4 in) on 18 July 1952.
Record daily precipitation for each month at Rockford
MonthRecord daily precipitation (mm)Date
Jan50.8 mm (2.0 in)24 January 1938
Feb33.8 mm (1.3 in)25 February 1926
Mar51.1 mm (2.0 in)25 March 1920
Apr64.3 mm (2.5 in)30 April 1911
May70.6 mm (2.8 in)27 May 1909
Jun118.6 mm (4.7 in)14 June 1926
Jul213.6 mm (8.4 in)18 July 1952
Aug114.3 mm (4.5 in)2 August 1942
Sep138.4 mm (5.4 in)9 September 1941
Oct111.3 mm (4.4 in)10 October 1954
Nov68.6 mm (2.7 in)17 November 1928
Dec59.2 mm (2.3 in)30 December 1936

Period of Record Coverage

1893 to 1957
Days with data per year at Rockford 60 years of record at Rockford, 1893 to 1957. 10 years have data for under 90 percent of days and are left out of rankings: 1893, 1895, 1898, 1903, 1904, 1905, 1920, 1946 and others. 1893: 272 of 365 days1895: 268 of 365 days1896: 351 of 366 days1897: 355 of 365 days1898: 243 of 365 days1903: 182 of 365 days1904: 180 of 366 days1905: 271 of 365 days1906: 350 of 365 days1907: 354 of 365 days1908: 358 of 366 days1909: 356 of 365 days1910: 362 of 365 days1911: 363 of 365 days1912: 363 of 366 days1913: 364 of 365 days1914: 363 of 365 days1915: 364 of 365 days1916: 365 of 366 days1917: 354 of 365 days1918: 353 of 365 days1919: 362 of 365 days1920: 302 of 366 days1921: 364 of 365 days1922: 365 of 365 days1923: 365 of 365 days1924: 366 of 366 days1925: 365 of 365 days1926: 365 of 365 days1927: 362 of 365 days1928: 366 of 366 days1929: 364 of 365 days1930: 365 of 365 days1931: 365 of 365 days1932: 366 of 366 days1933: 365 of 365 days1934: 365 of 365 days1935: 363 of 365 days1936: 366 of 366 days1937: 365 of 365 days1938: 365 of 365 days1939: 365 of 365 days1940: 366 of 366 days1941: 365 of 365 days1942: 365 of 365 days1943: 363 of 365 days1944: 364 of 366 days1945: 365 of 365 days1946: 88 of 365 days1947: 275 of 365 days1948: 366 of 366 days1949: 364 of 365 days1950: 360 of 365 days1951: 363 of 365 days1952: 363 of 366 days1953: 362 of 365 days1954: 365 of 365 days1955: 334 of 365 days1956: 364 of 366 days1957: 181 of 365 days19101920193019401950
60 years of record at Rockford, 1893 to 1957. 10 years have data for under 90 percent of days and are left out of rankings: 1893, 1895, 1898, 1903, 1904, 1905, 1920, 1946 and others.
Days with data per year at Rockford
YearDays with dataShare of yearComplete
189327275%No
189526873%No
189635196%Yes
189735597%Yes
189824367%No
190318250%No
190418049%No
190527174%No
190635096%Yes
190735497%Yes
190835898%Yes
190935698%Yes
191036299%Yes
191136399%Yes
191236399%Yes
1913364100%Yes
191436399%Yes
1915364100%Yes
1916365100%Yes
191735497%Yes
191835397%Yes
191936299%Yes
192030283%No
1921364100%Yes
1922365100%Yes
1923365100%Yes
1924366100%Yes
1925365100%Yes
1926365100%Yes
192736299%Yes
1928366100%Yes
1929364100%Yes
1930365100%Yes
1931365100%Yes
1932366100%Yes
1933365100%Yes
1934365100%Yes
193536399%Yes
1936366100%Yes
1937365100%Yes
1938365100%Yes
1939365100%Yes
1940366100%Yes
1941365100%Yes
1942365100%Yes
194336399%Yes
194436499%Yes
1945365100%Yes
19468824%No
194727575%No
1948366100%Yes
1949364100%Yes
195036099%Yes
195136399%Yes
195236399%Yes
195336299%Yes
1954365100%Yes
195533492%Yes
195636499%Yes
195718150%No

Latest Records

20
Latest records at Rockford
DateStationRecordValueBeat old record byOld record stoodSignificance
19 May 1957Rockford, USdaily low max9.4 C (48.9 F)1.7 C (3.1 F)61 years26 of 100 (Routine)
18 May 1957Rockford, USdaily rain29.5 mm (1.2 in)7.1 mm (0.28 in)58 years30 of 100 (Routine)
26 April 1957Rockford, USdaily high min (Tie)14.4 C (57.9 F)tie8 years2 of 100 (Routine)
20 April 1957Rockford, USdaily high min17.2 C (63.0 F)2.8 C (5.0 F)40 years23 of 100 (Routine)
14 April 1957Rockford, USdaily low min-6.7 C (19.9 F)0.6 C (1.1 F)50 years22 of 100 (Routine)
4 April 1957Rockford, USdaily rain15.5 mm (0.6 in)0.3 mm (0.01 in)23 years12 of 100 (Routine)
4 April 1957Rockford, USdaily snowfall (Tie)5.1 cm (2.0 in)tie7 years2 of 100 (Routine)
13 March 1957Rockford, USdaily high max21.1 C (70.0 F)1.7 C (3.1 F)35 years18 of 100 (Routine)
11 March 1957Rockford, USdaily high min5.6 C (42.1 F)1.2 C (2.2 F)36 years19 of 100 (Routine)
25 February 1957Rockford, USmonthly high min (Tie)8.9 C (48.0 F)tie27 years6 of 100 (Routine)
16 January 1957Rockford, USdaily low min-25.0 C (-13.0 F)0.6 C (1.1 F)63 years25 of 100 (Routine)
11 January 1957Rockford, USdaily rain8.9 mm (0.35 in)1.3 mm (0.05 in)31 years16 of 100 (Routine)
10 January 1957Rockford, USdaily snowfall10.2 cm (4.0 in)6.4 cm (2.5 in)12 years20 of 100 (Routine)
13 December 1956Rockford, USdaily low min-22.8 C (-9.0 F)2.8 C (5.0 F)37 years21 of 100 (Routine)
5 December 1956Rockford, USdaily high min7.8 C (46.0 F)2.2 C (4.0 F)47 years23 of 100 (Routine)
5 December 1956Rockford, USdaily high max15.6 C (60.1 F)3.4 C (6.1 F)13 years14 of 100 (Routine)
23 November 1956Rockford, USdaily low max-3.9 C (25.0 F)0.6 C (1.1 F)58 years23 of 100 (Routine)
15 November 1956Rockford, USdaily rain16.0 mm (0.6 in)3.3 mm (0.13 in)9 years11 of 100 (Routine)
5 November 1956Rockford, USdaily high min11.7 C (53.1 F)0.6 C (1.1 F)8 years9 of 100 (Routine)
20 September 1956Rockford, USdaily low min0.0 C (32.0 F)1.7 C (3.1 F)59 years26 of 100 (Routine)

Climate Trend

48 complete years, 1896 to 1956
Annual mean temperature at Rockford as warming stripes, 1896 to 1956 One stripe for each of 48 complete years at Rockford, 1896 to 1956. Blue stripes are years cooler than the station's own mean of 9.6 C (49.2 F); red stripes are warmer. The coolest year was 1917, at 7.1 C (44.9 F), and the warmest was 1921, at 11.6 C (52.8 F). The strongest colour marks a difference of 2.5 C (4.5 F). 1896: 10.2 C, +0.7 C from the station mean1897: 9.3 C, -0.3 C from the station mean1906: 10.1 C, +0.6 C from the station mean1907: 8.4 C, -1.1 C from the station mean1908: 9.9 C, +0.4 C from the station mean1909: 8.8 C, -0.8 C from the station mean1910: 8.7 C, -0.9 C from the station mean1911: 9.6 C, 0.0 C from the station mean1912: 7.5 C, -2.0 C from the station mean1913: 9.8 C, +0.2 C from the station mean1914: 9.5 C, -0.1 C from the station mean1915: 9.0 C, -0.6 C from the station mean1916: 9.0 C, -0.6 C from the station mean1917: 7.1 C, -2.4 C from the station mean1919: 8.9 C, -0.7 C from the station mean1921: 11.6 C, +2.0 C from the station mean1922: 10.5 C, +0.9 C from the station mean1923: 9.6 C, 0.0 C from the station mean1924: 7.9 C, -1.6 C from the station mean1925: 9.2 C, -0.4 C from the station mean1926: 8.5 C, -1.1 C from the station mean1927: 9.7 C, +0.1 C from the station mean1928: 10.0 C, +0.4 C from the station mean1929: 8.5 C, -1.1 C from the station mean1930: 10.1 C, +0.5 C from the station mean1931: 11.5 C, +2.0 C from the station mean1932: 9.6 C, 0.0 C from the station mean1933: 10.3 C, +0.8 C from the station mean1934: 10.8 C, +1.3 C from the station mean1935: 9.2 C, -0.3 C from the station mean1936: 9.1 C, -0.4 C from the station mean1937: 9.0 C, -0.5 C from the station mean1938: 10.7 C, +1.2 C from the station mean1939: 10.6 C, +1.1 C from the station mean1940: 8.9 C, -0.7 C from the station mean1941: 10.7 C, +1.1 C from the station mean1942: 9.8 C, +0.2 C from the station mean1943: 9.2 C, -0.4 C from the station mean1944: 10.1 C, +0.5 C from the station mean1945: 9.1 C, -0.4 C from the station mean1948: 9.9 C, +0.3 C from the station mean1949: 10.4 C, +0.9 C from the station mean1950: 8.6 C, -1.0 C from the station mean1951: 8.6 C, -1.0 C from the station mean1952: 10.4 C, +0.8 C from the station mean1953: 10.9 C, +1.3 C from the station mean1954: 10.4 C, +0.8 C from the station mean1956: 10.2 C, +0.6 C from the station mean1896190019101920193019401950
One stripe for each of 48 complete years at Rockford, 1896 to 1956. Blue stripes are years cooler than the station's own mean of 9.6 C (49.2 F); red stripes are warmer. The coolest year was 1917, at 7.1 C (44.9 F), and the warmest was 1921, at 11.6 C (52.8 F). The strongest colour marks a difference of 2.5 C (4.5 F).
Annual mean temperature at Rockford as warming stripes, 1896 to 1956
YearAnnual mean temperatureDifference from the station mean
189610.2 C+0.67 C
18979.3 C-0.27 C
190610.1 C+0.55 C
19078.4 C-1.14 C
19089.9 C+0.35 C
19098.8 C-0.78 C
19108.7 C-0.88 C
19119.6 C-0.01 C
19127.5 C-2.04 C
19139.8 C+0.24 C
19149.5 C-0.07 C
19159.0 C-0.60 C
19169.0 C-0.62 C
19177.1 C-2.43 C
19198.9 C-0.68 C
192111.6 C+1.99 C
192210.5 C+0.94 C
19239.6 C-0.02 C
19247.9 C-1.63 C
19259.2 C-0.39 C
19268.5 C-1.07 C
19279.7 C+0.14 C
192810.0 C+0.42 C
19298.5 C-1.11 C
193010.1 C+0.48 C
193111.5 C+1.97 C
19329.6 C+0.04 C
193310.3 C+0.75 C
193410.8 C+1.25 C
19359.2 C-0.34 C
19369.1 C-0.44 C
19379.0 C-0.53 C
193810.7 C+1.15 C
193910.6 C+1.05 C
19408.9 C-0.67 C
194110.7 C+1.08 C
19429.8 C+0.20 C
19439.2 C-0.41 C
194410.1 C+0.50 C
19459.1 C-0.45 C
19489.9 C+0.33 C
194910.4 C+0.85 C
19508.6 C-1.01 C
19518.6 C-0.98 C
195210.4 C+0.82 C
195310.9 C+1.28 C
195410.4 C+0.79 C
195610.2 C+0.61 C

The fitted trend in annual mean temperature here over 1896 to 1956 is 0.16 C (-0.01 to 0.33) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.29 F (-0.02 to 0.60) per decade. The slope is a straight line fitted to 48 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Rockford
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.16 C (-0.01 to 0.33) per decade0.29 F (-0.02 to 0.60) per decade1896 to 195648Not clearly different from zero
Mean daily maximum0.3 C (0.1 to 0.5) per decade0.6 F (0.2 to 0.9) per decade1896 to 195648Rise
Mean daily minimum0.02 C (-0.16 to 0.20) per decade0.03 F (-0.29 to 0.35) per decade1896 to 195648Not clearly different from zero

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

1893 to 1957
Yearly extremes at Rockford: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)44.4 C (111.9 F)193637.0 C (98.5 F)60
Coldest night (TNn)-31.7 C (-25.1 F)1924-25.0 C (-13.0 F)60
Wettest day (Rx1day)213.6 mm (8.4 in)195254.6 mm (2.1 in)61
Wettest five days (Rx5day)294.9 mm (11.6 in)195290.0 mm (3.5 in)61
Longest dry spell (CDD)46 days195222 days61

Hottest day (TXx)

Hottest day (TXx) at Rockford by year The hottest day of the year at Rockford, 1893 to 1957. The record is 44.4 C (111.9 F) in 1936, marked on the chart; the median year is 37.0 C (98.5 F). 2530354045190019201940Record: 44.4 C (111.9 F) in 1936
The hottest day of the year at Rockford, 1893 to 1957. The record is 44.4 C (111.9 F) in 1936, marked on the chart; the median year is 37.0 C (98.5 F).
Hottest day (TXx) at Rockford by year
YearHottest day (TXx)
189333.3 C (91.9 F)
1894n/a
189537.2 C (99.0 F)
189637.8 C (100.0 F)
189737.8 C (100.0 F)
189835.0 C (95.0 F)
190334.4 C (93.9 F)
190435.0 C (95.0 F)
190536.1 C (97.0 F)
190635.0 C (95.0 F)
190733.9 C (93.0 F)
190834.4 C (93.9 F)
190936.1 C (97.0 F)
191037.2 C (99.0 F)
191138.9 C (102.0 F)
191234.4 C (93.9 F)
191338.3 C (100.9 F)
191437.2 C (99.0 F)
191532.2 C (90.0 F)
191640.6 C (105.1 F)
191738.3 C (100.9 F)
191840.0 C (104.0 F)
191936.7 C (98.1 F)
192036.7 C (98.1 F)
192140.0 C (104.0 F)
192238.9 C (102.0 F)
192337.8 C (100.0 F)
192434.4 C (93.9 F)
192538.3 C (100.9 F)
192636.1 C (97.0 F)
192737.2 C (99.0 F)
192835.0 C (95.0 F)
192935.6 C (96.1 F)
193038.9 C (102.0 F)
193139.4 C (102.9 F)
193237.8 C (100.0 F)
193339.4 C (102.9 F)
193441.7 C (107.1 F)
193537.8 C (100.0 F)
193644.4 C (111.9 F)
193738.9 C (102.0 F)
193835.0 C (95.0 F)
193939.4 C (102.9 F)
194040.0 C (104.0 F)
194138.9 C (102.0 F)
194236.1 C (97.0 F)
194335.0 C (95.0 F)
194436.7 C (98.1 F)
194535.6 C (96.1 F)
194625.0 C (77.0 F)
194738.9 C (102.0 F)
194837.8 C (100.0 F)
194936.1 C (97.0 F)
195033.9 C (93.0 F)
195135.0 C (95.0 F)
195236.1 C (97.0 F)
195338.3 C (100.9 F)
195436.1 C (97.0 F)
195537.8 C (100.0 F)
195636.7 C (98.1 F)
195734.4 C (93.9 F)

Coldest night (TNn)

Coldest night (TNn) at Rockford by year The coldest night of the year at Rockford, 1893 to 1957. The record is -31.7 C (-25.1 F) in 1924, marked on the chart; the median year is -25.0 C (-13.0 F). -40-30-20-100190019201940Record: -31.7 C (-25.1 F) in 1924
The coldest night of the year at Rockford, 1893 to 1957. The record is -31.7 C (-25.1 F) in 1924, marked on the chart; the median year is -25.0 C (-13.0 F).
Coldest night (TNn) at Rockford by year
YearColdest night (TNn)
1893-28.3 C (-18.9 F)
1894n/a
1895-18.9 C (-2.0 F)
1896-23.3 C (-9.9 F)
1897-30.6 C (-23.1 F)
1898-22.2 C (-8.0 F)
1903-2.2 C (28.0 F)
1904-6.7 C (19.9 F)
1905-10.6 C (12.9 F)
1906-19.4 C (-2.9 F)
1907-22.8 C (-9.0 F)
1908-22.2 C (-8.0 F)
1909-23.9 C (-11.0 F)
1910-27.2 C (-17.0 F)
1911-21.1 C (-6.0 F)
1912-28.9 C (-20.0 F)
1913-22.8 C (-9.0 F)
1914-30.6 C (-23.1 F)
1915-30.0 C (-22.0 F)
1916-27.2 C (-17.0 F)
1917-27.8 C (-18.0 F)
1918-29.4 C (-20.9 F)
1919-29.4 C (-20.9 F)
1920-27.8 C (-18.0 F)
1921-19.4 C (-2.9 F)
1922-26.7 C (-16.1 F)
1923-24.4 C (-11.9 F)
1924-31.7 C (-25.1 F)
1925-26.7 C (-16.1 F)
1926-25.0 C (-13.0 F)
1927-28.9 C (-20.0 F)
1928-22.2 C (-8.0 F)
1929-30.0 C (-22.0 F)
1930-30.0 C (-22.0 F)
1931-20.0 C (-4.0 F)
1932-25.6 C (-14.1 F)
1933-31.7 C (-25.1 F)
1934-21.7 C (-7.1 F)
1935-25.6 C (-14.1 F)
1936-31.1 C (-24.0 F)
1937-20.0 C (-4.0 F)
1938-20.6 C (-5.1 F)
1939-18.3 C (-0.9 F)
1940-28.9 C (-20.0 F)
1941-23.3 C (-9.9 F)
1942-28.9 C (-20.0 F)
1943-25.0 C (-13.0 F)
1944-23.9 C (-11.0 F)
1945-24.4 C (-11.9 F)
1946-20.0 C (-4.0 F)
1947-22.2 C (-8.0 F)
1948-25.0 C (-13.0 F)
1949-25.0 C (-13.0 F)
1950-28.3 C (-18.9 F)
1951-30.0 C (-22.0 F)
1952-23.3 C (-9.9 F)
1953-23.3 C (-9.9 F)
1954-24.4 C (-11.9 F)
1955-25.6 C (-14.1 F)
1956-22.8 C (-9.0 F)
1957-25.6 C (-14.1 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Rockford by year The wettest day of the year at Rockford, 1893 to 1957. The record is 213.6 mm (8.4 in) in 1952, marked on the chart; the median year is 54.6 mm (2.1 in). 050100150200250190019201940Record: 213.6 mm (8.4 in) in 1952
The wettest day of the year at Rockford, 1893 to 1957. The record is 213.6 mm (8.4 in) in 1952, marked on the chart; the median year is 54.6 mm (2.1 in).
Wettest day (Rx1day) at Rockford by year
YearWettest day (Rx1day)
189368.3 mm (2.7 in)
189427.9 mm (1.1 in)
189533.5 mm (1.3 in)
189657.2 mm (2.3 in)
189735.6 mm (1.4 in)
189899.1 mm (3.9 in)
190350.8 mm (2.0 in)
190465.3 mm (2.6 in)
190553.3 mm (2.1 in)
190699.6 mm (3.9 in)
190744.2 mm (1.7 in)
190833.5 mm (1.3 in)
190970.6 mm (2.8 in)
191024.4 mm (1.0 in)
191164.3 mm (2.5 in)
191275.4 mm (3.0 in)
191367.3 mm (2.6 in)
191449.5 mm (1.9 in)
191543.7 mm (1.7 in)
191672.9 mm (2.9 in)
191734.5 mm (1.4 in)
191832.0 mm (1.3 in)
191963.8 mm (2.5 in)
192051.1 mm (2.0 in)
192144.5 mm (1.8 in)
192265.3 mm (2.6 in)
192346.2 mm (1.8 in)
192442.4 mm (1.7 in)
192531.2 mm (1.2 in)
1926118.6 mm (4.7 in)
192746.2 mm (1.8 in)
192868.6 mm (2.7 in)
192962.5 mm (2.5 in)
193048.3 mm (1.9 in)
193140.6 mm (1.6 in)
193236.8 mm (1.4 in)
193390.4 mm (3.6 in)
193436.3 mm (1.4 in)
193571.1 mm (2.8 in)
193672.4 mm (2.9 in)
193763.5 mm (2.5 in)
193850.8 mm (2.0 in)
193944.5 mm (1.8 in)
194085.1 mm (3.4 in)
1941138.4 mm (5.4 in)
1942114.3 mm (4.5 in)
194354.6 mm (2.1 in)
194457.2 mm (2.3 in)
194559.7 mm (2.4 in)
194648.5 mm (1.9 in)
194756.4 mm (2.2 in)
194839.9 mm (1.6 in)
194941.9 mm (1.6 in)
195081.3 mm (3.2 in)
195170.6 mm (2.8 in)
1952213.6 mm (8.4 in)
195358.9 mm (2.3 in)
1954111.3 mm (4.4 in)
195533.5 mm (1.3 in)
195653.8 mm (2.1 in)
195733.0 mm (1.3 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Rockford by year The wettest five days of the year at Rockford, 1893 to 1957. The record is 294.9 mm (11.6 in) in 1952, marked on the chart; the median year is 90.0 mm (3.5 in). 0100200300190019201940Record: 294.9 mm (11.6 in) in 1952
The wettest five days of the year at Rockford, 1893 to 1957. The record is 294.9 mm (11.6 in) in 1952, marked on the chart; the median year is 90.0 mm (3.5 in).
Wettest five days (Rx5day) at Rockford by year
YearWettest five days (Rx5day)
1893113.5 mm (4.5 in)
189447.0 mm (1.9 in)
189561.8 mm (2.4 in)
1896100.3 mm (3.9 in)
189760.9 mm (2.4 in)
189899.6 mm (3.9 in)
190399.1 mm (3.9 in)
190491.7 mm (3.6 in)
1905109.6 mm (4.3 in)
190699.6 mm (3.9 in)
190772.0 mm (2.8 in)
190857.4 mm (2.3 in)
1909116.8 mm (4.6 in)
191048.5 mm (1.9 in)
1911124.0 mm (4.9 in)
1912104.6 mm (4.1 in)
191374.2 mm (2.9 in)
191494.1 mm (3.7 in)
191574.7 mm (2.9 in)
1916113.8 mm (4.5 in)
191751.5 mm (2.0 in)
191850.0 mm (2.0 in)
191990.0 mm (3.5 in)
192065.8 mm (2.6 in)
192173.9 mm (2.9 in)
192292.0 mm (3.6 in)
192387.7 mm (3.5 in)
192481.9 mm (3.2 in)
192574.2 mm (2.9 in)
1926208.8 mm (8.2 in)
192791.7 mm (3.6 in)
192880.3 mm (3.2 in)
192974.2 mm (2.9 in)
193086.7 mm (3.4 in)
193164.0 mm (2.5 in)
193266.0 mm (2.6 in)
1933127.4 mm (5.0 in)
193498.8 mm (3.9 in)
1935130.3 mm (5.1 in)
1936112.0 mm (4.4 in)
193780.8 mm (3.2 in)
1938114.5 mm (4.5 in)
193968.7 mm (2.7 in)
194096.3 mm (3.8 in)
1941140.9 mm (5.5 in)
1942160.7 mm (6.3 in)
194369.6 mm (2.7 in)
194474.6 mm (2.9 in)
1945105.0 mm (4.1 in)
1946100.4 mm (4.0 in)
194777.2 mm (3.0 in)
194872.4 mm (2.9 in)
194967.0 mm (2.6 in)
1950137.2 mm (5.4 in)
1951102.1 mm (4.0 in)
1952294.9 mm (11.6 in)
195378.2 mm (3.1 in)
1954119.9 mm (4.7 in)
195556.4 mm (2.2 in)
1956100.0 mm (3.9 in)
195757.1 mm (2.2 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Rockford by year The longest dry spell of the year at Rockford, 1893 to 1957. The record is 46 days in 1952, marked on the chart; the median year is 22 days. 1020304050190019201940Record: 46 days in 1952
The longest dry spell of the year at Rockford, 1893 to 1957. The record is 46 days in 1952, marked on the chart; the median year is 22 days.
Longest dry spell (CDD) at Rockford by year
YearLongest dry spell (CDD)
189315 days
189418 days
189521 days
189620 days
189724 days
189823 days
190311 days
190410 days
190529 days
190623 days
190723 days
190826 days
190916 days
191022 days
191118 days
191225 days
191325 days
191417 days
191524 days
191620 days
191728 days
191819 days
191937 days
192020 days
192125 days
192235 days
192319 days
192426 days
192536 days
192624 days
192720 days
192826 days
192916 days
193019 days
193117 days
193223 days
193338 days
193438 days
193516 days
193626 days
193735 days
193822 days
193929 days
194017 days
194114 days
194229 days
194325 days
194427 days
194516 days
194615 days
194721 days
194822 days
194921 days
195030 days
195117 days
195246 days
195323 days
195419 days
195518 days
195617 days
195713 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

48 years with a frost

Across 48 years with a frost, the median last spring frost at Rockford falls on 3 May and the median first autumn frost on 7 October, which leaves a median of 161 days between them.

Fitted over all years, the growing season changes by -1.4 days per decade at this station.

Frost dates and growing season at Rockford
MeasureMedian, all yearsEarliest periodRecent period (1924 to 1956)Recent against earliestFitted trend
Last spring frost3 Mayn/a4 Mayn/a-0.1 days per decade
First autumn frost7 Octobern/a5 Octobern/a-1.4 days per decade
Growing days161 daysn/a158 daysn/a-1.4 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

51 years, 1895 to 1956

A day with at least 54.0 mm (2.1 in) of rain is expected about once in 2 years. A day with at least 192.3 mm (7.6 in) of rain is expected about once in 100 years.

Rainfall return levels at Rockford: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years54.0 mm (2.1 in)
5 years78.9 mm (3.1 in)
10 years99.4 mm (3.9 in)
25 years131.0 mm (5.2 in)
50 years159.3 mm (6.3 in)
100 years192.3 mm (7.6 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 1895 to 1956.

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: 213.6 mm (8.4 in) in 1952; 138.4 mm (5.4 in) in 1941; 118.6 mm (4.7 in) in 1926.

Station Changes

No change in the annual mean temperature of this station was found against its neighbours.

Download the Data

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