Port Radium Weather Records (CA002203300)

Record envelope, standing records and threshold days for Port Radium (CA002203300), Northwest Territories, Canada, with 38 years of record.

Key Facts for Port Radium

Port Radium (CA002203300) is a weather station in Northwest Territories, Canada at 66.08 latitude and -118.03 longitude, 191 m (627 ft) above sea level.
The station reports from 1937 to 1974, 38 years of record.
1,464 records set at Port Radium still stand.
Records are tracked for no element yet: an element needs 30 years of data to be eligible.

About the Station

Location: Northwest Territories, Canada, 66.08 latitude, -118.03 longitude.
Elevation: 191 m (627 ft).
Period of record: 1937 to 1974, 38 years.
Eligible elements: none yet.

Daily Record Envelope and 2026

0 days at or beyond a record

The band shows the record high and record low for each calendar day at Port Radium. 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 Port Radium, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	-2.2 C (28.0 F)	-47.8 C (-54.0 F)	n/a	n/a
Feb	3.3 C (37.9 F)	-47.2 C (-53.0 F)	n/a	n/a
Mar	6.1 C (43.0 F)	-43.9 C (-47.0 F)	n/a	n/a
Apr	14.4 C (57.9 F)	-38.3 C (-36.9 F)	n/a	n/a
May	26.7 C (80.1 F)	-26.1 C (-15.0 F)	n/a	n/a
Jun	30.6 C (87.1 F)	-6.1 C (21.0 F)	n/a	n/a
Jul	30.0 C (86.0 F)	-1.1 C (30.0 F)	n/a	n/a
Aug	29.4 C (84.9 F)	-2.8 C (27.0 F)	n/a	n/a
Sep	23.9 C (75.0 F)	-9.4 C (15.1 F)	n/a	n/a
Oct	16.7 C (62.1 F)	-20.0 C (-4.0 F)	n/a	n/a
Nov	7.8 C (46.0 F)	-41.1 C (-42.0 F)	n/a	n/a
Dec	1.1 C (34.0 F)	-49.4 C (-56.9 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Port Radium still stand. 1956 holds the most, with 90.

Standing records at Port Radium by the year they were set
Year set	Standing records
1937	18
1938	74
1939	73
1940	33
1942	11
1943	60
1944	53
1945	37
1946	40
1947	52
1948	47
1949	64
1950	25
1951	52
1952	33
1953	31
1954	73
1955	68
1956	90
1957	60
1958	34
1959	66
1960	45
1961	1
1967	6
1968	28
1969	77
1970	44
1971	26
1972	32
1973	63
1974	48

Wettest Day of Each Month

Jul: 52.1 mm (2.1 in)

The wettest day on record for each calendar month at Port Radium. The most was 52.1 mm (2.1 in) on 29 July 1948.

Record daily precipitation for each month at Port Radium
Month	Record daily precipitation (mm)	Date
Jan	7.6 mm (0.30 in)	2 January 1958
Feb	11.9 mm (0.5 in)	21 February 1974
Mar	12.7 mm (0.5 in)	27 March 1938
Apr	7.6 mm (0.30 in)	27 April 1958
May	25.9 mm (1.0 in)	8 May 1948
Jun	23.1 mm (0.9 in)	9 June 1944
Jul	52.1 mm (2.1 in)	29 July 1948
Aug	34.5 mm (1.4 in)	13 August 1973
Sep	32.5 mm (1.3 in)	4 September 1950
Oct	27.9 mm (1.1 in)	20 October 1971
Nov	13.0 mm (0.5 in)	25 November 1957
Dec	10.9 mm (0.4 in)	5 December 1956

Period of Record Coverage

1937 to 1974

32 years of record at Port Radium, 1937 to 1974. 8 years have data for under 90 percent of days and are left out of rankings: 1937, 1940, 1942, 1943, 1961, 1967, 1968, 1974.

Days with data per year at Port Radium
Year	Days with data	Share of year	Complete
1937	31	8%	No
1938	359	98%	Yes
1939	335	92%	Yes
1940	182	50%	No
1942	70	19%	No
1943	242	66%	No
1944	365	100%	Yes
1945	365	100%	Yes
1946	365	100%	Yes
1947	346	95%	Yes
1948	366	100%	Yes
1949	365	100%	Yes
1950	365	100%	Yes
1951	365	100%	Yes
1952	366	100%	Yes
1953	365	100%	Yes
1954	365	100%	Yes
1955	365	100%	Yes
1956	366	100%	Yes
1957	365	100%	Yes
1958	365	100%	Yes
1959	365	100%	Yes
1960	366	100%	Yes
1961	28	8%	No
1967	82	22%	No
1968	329	90%	No
1969	364	100%	Yes
1970	361	99%	Yes
1971	356	98%	Yes
1972	358	98%	Yes
1973	364	100%	Yes
1974	267	73%	No

Latest Records

No records were set at this station in the latest data.

Climate Trend

22 complete years, 1938 to 1973

One stripe for each of 22 complete years at Port Radium, 1938 to 1973. Blue stripes are years cooler than the station's own mean of -7.0 C (19.4 F); red stripes are warmer. The coolest year was 1956, at -9.0 C (15.9 F), and the warmest was 1973, at -5.0 C (23.0 F). The strongest colour marks a difference of 2.0 C (3.6 F).

Annual mean temperature at Port Radium as warming stripes, 1938 to 1973
Year	Annual mean temperature	Difference from the station mean
1938	-6.1 C	+0.88 C
1944	-5.6 C	+1.38 C
1945	-7.2 C	-0.22 C
1946	-7.3 C	-0.26 C
1948	-6.5 C	+0.47 C
1949	-6.4 C	+0.59 C
1950	-8.0 C	-0.97 C
1951	-8.2 C	-1.21 C
1952	-6.3 C	+0.70 C
1953	-5.6 C	+1.38 C
1954	-6.3 C	+0.67 C
1955	-8.0 C	-1.01 C
1956	-9.0 C	-1.96 C
1957	-7.3 C	-0.29 C
1958	-6.9 C	+0.06 C
1959	-8.9 C	-1.94 C
1960	-7.1 C	-0.12 C
1969	-5.8 C	+1.15 C
1970	-7.0 C	+0.00 C
1971	-6.6 C	+0.36 C
1972	-8.7 C	-1.71 C
1973	-5.0 C	+1.98 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

1937 to 1974

Yearly extremes at Port Radium: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	30.6 C (87.1 F)	1955	26.4 C (79.5 F)	32
Coldest night (TNn)	-49.4 C (-56.9 F)	1937	-42.8 C (-45.0 F)	32
Wettest day (Rx1day)	52.1 mm (2.1 in)	1948	17.7 mm (0.7 in)	32
Wettest five days (Rx5day)	88.4 mm (3.5 in)	1939	24.3 mm (1.0 in)	32
Longest dry spell (CDD)	60 days	1940	35 days	32

Hottest day (TXx)

The hottest day of the year at Port Radium, 1937 to 1974. The record is 30.6 C (87.1 F) in 1955, marked on the chart; the median year is 26.4 C (79.5 F).

Hottest day (TXx) at Port Radium by year
Year	Hottest day (TXx)
1937	-11.1 C (12.0 F)
1938	30.0 C (86.0 F)
1939	27.8 C (82.0 F)
1940	20.0 C (68.0 F)
1942	16.1 C (61.0 F)
1943	17.2 C (63.0 F)
1944	26.1 C (79.0 F)
1945	26.1 C (79.0 F)
1946	26.7 C (80.1 F)
1947	23.9 C (75.0 F)
1948	28.9 C (84.0 F)
1949	26.7 C (80.1 F)
1950	24.4 C (75.9 F)
1951	27.8 C (82.0 F)
1952	25.6 C (78.1 F)
1953	27.2 C (81.0 F)
1954	28.9 C (84.0 F)
1955	30.6 C (87.1 F)
1956	26.7 C (80.1 F)
1957	26.1 C (79.0 F)
1958	23.9 C (75.0 F)
1959	27.2 C (81.0 F)
1960	26.1 C (79.0 F)
1961	-15.6 C (3.9 F)
1967	6.1 C (43.0 F)
1968	25.6 C (78.1 F)
1969	26.7 C (80.1 F)
1970	27.8 C (82.0 F)
1971	29.4 C (84.9 F)
1972	27.2 C (81.0 F)
1973	29.4 C (84.9 F)
1974	26.1 C (79.0 F)

Coldest night (TNn)

The coldest night of the year at Port Radium, 1937 to 1974. The record is -49.4 C (-56.9 F) in 1937, marked on the chart; the median year is -42.8 C (-45.0 F).

Coldest night (TNn) at Port Radium by year
Year	Coldest night (TNn)
1937	-49.4 C (-56.9 F)
1938	-46.7 C (-52.1 F)
1939	-47.2 C (-53.0 F)
1940	-44.4 C (-47.9 F)
1942	-37.2 C (-35.0 F)
1943	-47.8 C (-54.0 F)
1944	-39.4 C (-38.9 F)
1945	-39.4 C (-38.9 F)
1946	-42.8 C (-45.0 F)
1947	-45.6 C (-50.1 F)
1948	-38.3 C (-36.9 F)
1949	-40.0 C (-40.0 F)
1950	-41.1 C (-42.0 F)
1951	-41.1 C (-42.0 F)
1952	-43.3 C (-45.9 F)
1953	-41.7 C (-43.1 F)
1954	-42.8 C (-45.0 F)
1955	-43.3 C (-45.9 F)
1956	-43.9 C (-47.0 F)
1957	-42.8 C (-45.0 F)
1958	-45.0 C (-49.0 F)
1959	-41.7 C (-43.1 F)
1960	-42.2 C (-44.0 F)
1961	-37.8 C (-36.0 F)
1967	-31.7 C (-25.1 F)
1968	-46.7 C (-52.1 F)
1969	-39.4 C (-38.9 F)
1970	-44.4 C (-47.9 F)
1971	-45.0 C (-49.0 F)
1972	-42.8 C (-45.0 F)
1973	-43.3 C (-45.9 F)
1974	-42.2 C (-44.0 F)

Wettest day (Rx1day)

The wettest day of the year at Port Radium, 1937 to 1974. The record is 52.1 mm (2.1 in) in 1948, marked on the chart; the median year is 17.7 mm (0.7 in).

Wettest day (Rx1day) at Port Radium by year
Year	Wettest day (Rx1day)
1937	7.6 mm (0.30 in)
1938	31.8 mm (1.3 in)
1939	41.9 mm (1.6 in)
1940	15.5 mm (0.6 in)
1942	7.6 mm (0.30 in)
1943	20.3 mm (0.8 in)
1944	23.1 mm (0.9 in)
1945	31.0 mm (1.2 in)
1946	13.5 mm (0.5 in)
1947	15.0 mm (0.6 in)
1948	52.1 mm (2.1 in)
1949	8.9 mm (0.35 in)
1950	32.5 mm (1.3 in)
1951	46.5 mm (1.8 in)
1952	17.0 mm (0.7 in)
1953	38.1 mm (1.5 in)
1954	32.5 mm (1.3 in)
1955	17.0 mm (0.7 in)
1956	19.6 mm (0.8 in)
1957	14.0 mm (0.6 in)
1958	15.5 mm (0.6 in)
1959	10.9 mm (0.4 in)
1960	15.5 mm (0.6 in)
1961	1.3 mm (0.05 in)
1967	5.6 mm (0.22 in)
1968	10.7 mm (0.4 in)
1969	20.3 mm (0.8 in)
1970	18.3 mm (0.7 in)
1971	27.9 mm (1.1 in)
1972	8.1 mm (0.32 in)
1973	34.5 mm (1.4 in)
1974	29.2 mm (1.1 in)

Wettest five days (Rx5day)

The wettest five days of the year at Port Radium, 1937 to 1974. The record is 88.4 mm (3.5 in) in 1939, marked on the chart; the median year is 24.3 mm (1.0 in).

Wettest five days (Rx5day) at Port Radium by year
Year	Wettest five days (Rx5day)
1937	9.7 mm (0.38 in)
1938	55.6 mm (2.2 in)
1939	88.4 mm (3.5 in)
1940	22.4 mm (0.9 in)
1942	16.4 mm (0.6 in)
1943	25.6 mm (1.0 in)
1944	23.9 mm (0.9 in)
1945	37.1 mm (1.5 in)
1946	22.2 mm (0.9 in)
1947	18.5 mm (0.7 in)
1948	80.8 mm (3.2 in)
1949	13.7 mm (0.5 in)
1950	37.4 mm (1.5 in)
1951	50.1 mm (2.0 in)
1952	28.0 mm (1.1 in)
1953	45.9 mm (1.8 in)
1954	37.8 mm (1.5 in)
1955	19.6 mm (0.8 in)
1956	24.7 mm (1.0 in)
1957	19.3 mm (0.8 in)
1958	22.6 mm (0.9 in)
1959	17.5 mm (0.7 in)
1960	31.3 mm (1.2 in)
1961	2.1 mm (0.08 in)
1967	10.7 mm (0.4 in)
1968	13.5 mm (0.5 in)
1969	32.2 mm (1.3 in)
1970	19.6 mm (0.8 in)
1971	43.7 mm (1.7 in)
1972	15.7 mm (0.6 in)
1973	46.7 mm (1.8 in)
1974	34.8 mm (1.4 in)

Longest dry spell (CDD)

The longest dry spell of the year at Port Radium, 1937 to 1974. The record is 60 days in 1940, marked on the chart; the median year is 35 days.

Longest dry spell (CDD) at Port Radium by year
Year	Longest dry spell (CDD)
1937	11 days
1938	54 days
1939	52 days
1940	60 days
1942	19 days
1943	35 days
1944	36 days
1945	34 days
1946	58 days
1947	52 days
1948	47 days
1949	23 days
1950	21 days
1951	33 days
1952	23 days
1953	43 days
1954	46 days
1955	30 days
1956	39 days
1957	40 days
1958	32 days
1959	31 days
1960	49 days
1961	19 days
1967	17 days
1968	41 days
1969	31 days
1970	47 days
1971	27 days
1972	20 days
1973	20 days
1974	40 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

22 years with a frost

Across 22 years with a frost, the median last spring frost at Port Radium falls on 18 June and the median first autumn frost on 3 September, which leaves a median of 77 days between them.

Frost dates and growing season at Port Radium
Measure	Median, all years	Earliest period	Recent period (1938 to 1973)	Recent against earliest	Fitted trend
Last spring frost	18 June	n/a	18 June	n/a	n/a
First autumn frost	3 September	n/a	3 September	n/a	n/a
Growing days	77 days	n/a	77 days	n/a	n/a

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 Port Radium standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Port Radium 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 2026-10-15. Last revised 15 October 2026 (2026-10-15).