Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Shamrock. 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 Shamrock, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
11.1 C (52.0 F)
-40.6 C (-41.1 F)
n/a
n/a
Feb
11.7 C (53.1 F)
-38.9 C (-38.0 F)
n/a
n/a
Mar
21.1 C (70.0 F)
-36.7 C (-34.1 F)
n/a
n/a
Apr
31.7 C (89.1 F)
-26.7 C (-16.1 F)
n/a
n/a
May
37.8 C (100.0 F)
-9.4 C (15.1 F)
n/a
n/a
Jun
35.0 C (95.0 F)
-2.8 C (27.0 F)
n/a
n/a
Jul
38.9 C (102.0 F)
2.2 C (36.0 F)
n/a
n/a
Aug
39.0 C (102.2 F)
0.0 C (32.0 F)
n/a
n/a
Sep
37.0 C (98.6 F)
-10.0 C (14.0 F)
n/a
n/a
Oct
31.1 C (88.0 F)
-19.4 C (-2.9 F)
n/a
n/a
Nov
22.2 C (72.0 F)
-32.2 C (-26.0 F)
n/a
n/a
Dec
11.1 C (52.0 F)
-40.5 C (-40.9 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Shamrock still stand. 1963 holds the most, with 76.
Standing records at Shamrock by the year they were set
Year set
Standing records
1956
41
1957
48
1958
47
1959
58
1960
47
1961
61
1962
61
1963
76
1964
52
1965
67
1966
69
1967
48
1968
66
1969
61
1970
32
1971
37
1972
67
1973
58
1974
40
1975
41
1976
43
1977
60
1978
30
1979
43
1980
55
1981
49
1982
46
1983
61
All-Time Record Progression
1 new records
1 all-time records were set at Shamrock between 27 September 1982 and 27 September 1982. Each dot is a new record.
When Shamrock set new all-time records
Date
Kind
Detail
1982-09-27
Record daily snowfall
Record daily snowfall 30.0 cm (11.8 in)
Wettest Day of Each Month
Aug: 61.0 mm (2.4 in)
The wettest day on record for each calendar month at Shamrock. The most was 61.0 mm (2.4 in) on 15 August 1972.
Record daily precipitation for each month at Shamrock
Month
Record daily precipitation (mm)
Date
Jan
20.3 mm (0.8 in)
30 January 1965
Feb
17.8 mm (0.7 in)
27 February 1948
Mar
20.3 mm (0.8 in)
28 March 1977
Apr
25.9 mm (1.0 in)
13 April 1973
May
56.1 mm (2.2 in)
20 May 1974
Jun
42.2 mm (1.7 in)
29 June 1978
Jul
53.3 mm (2.1 in)
5 July 1946
Aug
61.0 mm (2.4 in)
15 August 1972
Sep
55.9 mm (2.2 in)
10 September 1978
Oct
25.7 mm (1.0 in)
2 October 1969
Nov
17.8 mm (0.7 in)
16 November 1966
Dec
20.3 mm (0.8 in)
17 December 1961
Period of Record Coverage
1956 to 1983
Complete yearUnder 90 percent of days
28 years of record at Shamrock, 1956 to 1983. 1 years have data for under 90 percent of days and are left out of rankings: 1956.
Cooler than the station meanWarmer than the station mean
One stripe for each of 26 complete years at Shamrock, 1957 to 1983. Blue stripes are years cooler than the station's own mean of 3.1 C (37.6 F); red stripes are warmer. The coolest year was 1965, at 1.7 C (35.0 F), and the warmest was 1981, at 5.8 C (42.4 F). The strongest colour marks a difference of 2.7 C (4.9 F).
Annual mean temperature at Shamrock as warming stripes, 1957 to 1983
Year
Annual mean temperature
Difference from the station mean
1957
3.2 C
+0.08 C
1959
2.8 C
-0.38 C
1960
3.3 C
+0.19 C
1961
4.1 C
+0.92 C
1962
3.6 C
+0.50 C
1963
4.2 C
+1.09 C
1964
3.4 C
+0.23 C
1965
1.7 C
-1.47 C
1966
2.3 C
-0.80 C
1967
2.9 C
-0.28 C
1968
3.6 C
+0.41 C
1969
2.3 C
-0.81 C
1970
2.3 C
-0.88 C
1971
2.8 C
-0.37 C
1972
1.8 C
-1.35 C
1973
4.1 C
+0.95 C
1974
3.0 C
-0.19 C
1975
2.3 C
-0.85 C
1976
4.2 C
+1.10 C
1977
3.9 C
+0.76 C
1978
2.3 C
-0.86 C
1979
2.5 C
-0.66 C
1980
3.7 C
+0.57 C
1981
5.8 C
+2.62 C
1982
1.8 C
-1.39 C
1983
4.0 C
+0.83 C
This station does not have enough complete years (30 are needed) to fit a temperature trend.
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
1945 to 1983
Yearly extremes at Shamrock: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
39.0 C (102.2 F)
1983
36.7 C (98.1 F)
28
Coldest night (TNn)
-40.6 C (-41.1 F)
1972
-36.1 C (-33.0 F)
28
Wettest day (Rx1day)
61.0 mm (2.4 in)
1972
31.8 mm (1.3 in)
35
Wettest five days (Rx5day)
109.5 mm (4.3 in)
1978
48.3 mm (1.9 in)
35
Longest dry spell (CDD)
58 days
1960
33 days
35
Hottest day (TXx)
The hottest day of the year at Shamrock, 1945 to 1983. The record is 39.0 C (102.2 F) in 1983, marked on the chart; the median year is 36.7 C (98.1 F).
Hottest day (TXx) at Shamrock by year
Year
Hottest day (TXx)
1945
n/a
1946
n/a
1947
n/a
1948
n/a
1949
n/a
1950
n/a
1951
n/a
1956
35.6 C (96.1 F)
1957
37.2 C (99.0 F)
1958
37.8 C (100.0 F)
1959
38.9 C (102.0 F)
1960
36.7 C (98.1 F)
1961
38.3 C (100.9 F)
1962
32.2 C (90.0 F)
1963
36.1 C (97.0 F)
1964
35.6 C (96.1 F)
1965
34.4 C (93.9 F)
1966
36.7 C (98.1 F)
1967
36.1 C (97.0 F)
1968
35.0 C (95.0 F)
1969
37.8 C (100.0 F)
1970
37.2 C (99.0 F)
1971
37.2 C (99.0 F)
1972
36.1 C (97.0 F)
1973
37.2 C (99.0 F)
1974
34.4 C (93.9 F)
1975
37.2 C (99.0 F)
1976
36.7 C (98.1 F)
1977
33.3 C (91.9 F)
1978
36.7 C (98.1 F)
1979
35.6 C (96.1 F)
1980
37.8 C (100.0 F)
1981
36.5 C (97.7 F)
1982
32.0 C (89.6 F)
1983
39.0 C (102.2 F)
Coldest night (TNn)
The coldest night of the year at Shamrock, 1945 to 1983. The record is -40.6 C (-41.1 F) in 1972, marked on the chart; the median year is -36.1 C (-33.0 F).
Coldest night (TNn) at Shamrock by year
Year
Coldest night (TNn)
1945
n/a
1946
n/a
1947
n/a
1948
n/a
1949
n/a
1950
n/a
1951
n/a
1956
-35.6 C (-32.1 F)
1957
-35.0 C (-31.0 F)
1958
-33.9 C (-29.0 F)
1959
-36.1 C (-33.0 F)
1960
-32.2 C (-26.0 F)
1961
-36.1 C (-33.0 F)
1962
-38.9 C (-38.0 F)
1963
-34.4 C (-29.9 F)
1964
-34.4 C (-29.9 F)
1965
-35.0 C (-31.0 F)
1966
-36.7 C (-34.1 F)
1967
-36.1 C (-33.0 F)
1968
-40.0 C (-40.0 F)
1969
-37.8 C (-36.0 F)
1970
-38.3 C (-36.9 F)
1971
-35.0 C (-31.0 F)
1972
-40.6 C (-41.1 F)
1973
-32.2 C (-26.0 F)
1974
-37.2 C (-35.0 F)
1975
-33.3 C (-27.9 F)
1976
-35.0 C (-31.0 F)
1977
-40.0 C (-40.0 F)
1978
-33.3 C (-27.9 F)
1979
-36.7 C (-34.1 F)
1980
-36.7 C (-34.1 F)
1981
-30.6 C (-23.1 F)
1982
-38.0 C (-36.4 F)
1983
-40.5 C (-40.9 F)
Wettest day (Rx1day)
The wettest day of the year at Shamrock, 1945 to 1983. The record is 61.0 mm (2.4 in) in 1972, marked on the chart; the median year is 31.8 mm (1.3 in).
Wettest day (Rx1day) at Shamrock by year
Year
Wettest day (Rx1day)
1945
12.2 mm (0.5 in)
1946
53.3 mm (2.1 in)
1947
30.5 mm (1.2 in)
1948
42.4 mm (1.7 in)
1949
41.7 mm (1.6 in)
1950
23.6 mm (0.9 in)
1951
15.2 mm (0.6 in)
1956
24.6 mm (1.0 in)
1957
17.5 mm (0.7 in)
1958
29.2 mm (1.1 in)
1959
43.9 mm (1.7 in)
1960
34.5 mm (1.4 in)
1961
33.3 mm (1.3 in)
1962
51.3 mm (2.0 in)
1963
60.2 mm (2.4 in)
1964
21.3 mm (0.8 in)
1965
27.4 mm (1.1 in)
1966
31.8 mm (1.3 in)
1967
31.0 mm (1.2 in)
1968
21.3 mm (0.8 in)
1969
37.6 mm (1.5 in)
1970
36.3 mm (1.4 in)
1971
20.6 mm (0.8 in)
1972
61.0 mm (2.4 in)
1973
25.9 mm (1.0 in)
1974
56.1 mm (2.2 in)
1975
27.2 mm (1.1 in)
1976
32.0 mm (1.3 in)
1977
20.3 mm (0.8 in)
1978
55.9 mm (2.2 in)
1979
38.9 mm (1.5 in)
1980
33.8 mm (1.3 in)
1981
30.0 mm (1.2 in)
1982
37.0 mm (1.5 in)
1983
30.4 mm (1.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Shamrock, 1945 to 1983. The record is 109.5 mm (4.3 in) in 1978, marked on the chart; the median year is 48.3 mm (1.9 in).
Wettest five days (Rx5day) at Shamrock by year
Year
Wettest five days (Rx5day)
1945
12.2 mm (0.5 in)
1946
63.2 mm (2.5 in)
1947
53.3 mm (2.1 in)
1948
45.4 mm (1.8 in)
1949
48.3 mm (1.9 in)
1950
37.7 mm (1.5 in)
1951
20.4 mm (0.8 in)
1956
48.3 mm (1.9 in)
1957
26.9 mm (1.1 in)
1958
42.4 mm (1.7 in)
1959
51.7 mm (2.0 in)
1960
88.1 mm (3.5 in)
1961
35.8 mm (1.4 in)
1962
54.1 mm (2.1 in)
1963
61.2 mm (2.4 in)
1964
30.2 mm (1.2 in)
1965
42.1 mm (1.7 in)
1966
53.6 mm (2.1 in)
1967
75.9 mm (3.0 in)
1968
48.3 mm (1.9 in)
1969
66.1 mm (2.6 in)
1970
61.2 mm (2.4 in)
1971
38.6 mm (1.5 in)
1972
71.4 mm (2.8 in)
1973
33.8 mm (1.3 in)
1974
83.3 mm (3.3 in)
1975
39.7 mm (1.6 in)
1976
48.3 mm (1.9 in)
1977
43.5 mm (1.7 in)
1978
109.5 mm (4.3 in)
1979
51.3 mm (2.0 in)
1980
33.8 mm (1.3 in)
1981
63.1 mm (2.5 in)
1982
64.0 mm (2.5 in)
1983
50.0 mm (2.0 in)
Longest dry spell (CDD)
The longest dry spell of the year at Shamrock, 1945 to 1983. The record is 58 days in 1960, marked on the chart; the median year is 33 days.
Longest dry spell (CDD) at Shamrock by year
Year
Longest dry spell (CDD)
1945
19 days
1946
31 days
1947
27 days
1948
40 days
1949
44 days
1950
25 days
1951
14 days
1956
35 days
1957
22 days
1958
24 days
1959
53 days
1960
58 days
1961
32 days
1962
29 days
1963
44 days
1964
54 days
1965
33 days
1966
40 days
1967
26 days
1968
56 days
1969
42 days
1970
35 days
1971
27 days
1972
26 days
1973
33 days
1974
38 days
1975
37 days
1976
34 days
1977
38 days
1978
30 days
1979
26 days
1980
48 days
1981
26 days
1982
20 days
1983
22 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
26 years with a frost
Across 26 years with a frost, the median last spring frost at Shamrock falls on 17 May and the median first autumn frost on 15 September, which leaves a median of 119 days between them.
Fitted over all years, the growing season changes by +4.1 days per decade at this station.
Frost dates and growing season at Shamrock
Measure
Median, all years
Earliest period
Recent period (1957 to 1983)
Recent against earliest
Fitted trend
Last spring frost
17 May
n/a
17 May
n/a
-3.4 days per decade
First autumn frost
15 September
n/a
15 September
n/a
+0.6 days per decade
Growing days
119 days
n/a
119 days
n/a
+4.1 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.
Download the Data
Data for Shamrock standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Shamrock 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.