Mill Bay Weather Records (CA001065130)

Record envelope, standing records and threshold days for Mill Bay (CA001065130), British Columbia, Canada, with 45 years of record.

Key Facts for Mill Bay

Mill Bay (CA001065130) is a weather station in British Columbia, Canada at 55.00 latitude and -129.75 longitude, 3 m (10 ft) above sea level.
The station reports from 1915 to 1959, 45 years of record.
1,464 records set at Mill Bay still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Mill Bay set a daily record snowfall of 26.7 cm (10.5 in) on 21 March 1959.

About the Station

Location: British Columbia, Canada, 55.00 latitude, -129.75 longitude.
Elevation: 3 m (10 ft).
Period of record: 1915 to 1959, 45 years.
Eligible elements: tmax, tmin, prcp, snow.

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 Mill Bay. 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 Mill Bay, 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)	-27.8 C (-18.0 F)	n/a	n/a
Feb	13.9 C (57.0 F)	-23.3 C (-9.9 F)	n/a	n/a
Mar	20.0 C (68.0 F)	-15.6 C (3.9 F)	n/a	n/a
Apr	24.4 C (75.9 F)	-6.7 C (19.9 F)	n/a	n/a
May	30.6 C (87.1 F)	-2.2 C (28.0 F)	n/a	n/a
Jun	34.4 C (93.9 F)	-0.6 C (30.9 F)	n/a	n/a
Jul	32.2 C (90.0 F)	1.7 C (35.1 F)	n/a	n/a
Aug	31.1 C (88.0 F)	-0.6 C (30.9 F)	n/a	n/a
Sep	30.6 C (87.1 F)	0.0 C (32.0 F)	n/a	n/a
Oct	22.2 C (72.0 F)	-7.2 C (19.0 F)	n/a	n/a
Nov	15.0 C (59.0 F)	-14.4 C (6.1 F)	n/a	n/a
Dec	11.7 C (53.1 F)	-22.8 C (-9.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Mill Bay still stand. 1925 holds the most, with 99.

Standing records at Mill Bay by the year they were set
Year set	Standing records
1915	26
1916	38
1917	29
1918	33
1919	67
1920	30
1921	17
1922	31
1923	23
1924	33
1925	99
1926	78
1927	25
1928	18
1929	32
1930	38
1931	20
1932	23
1933	48
1934	22
1935	35
1936	49
1937	29
1938	23
1939	18
1940	34
1941	29
1942	47
1943	19
1944	34
1945	13
1946	22
1947	23
1948	29
1949	29
1950	51
1951	24
1952	18
1953	17
1954	25
1955	47
1956	36
1957	21
1958	60
1959	2

All-Time Record Progression

12 new records

12 all-time records were set at Mill Bay between 12 January 1946 and 30 June 1958. Each dot is a new record.

When Mill Bay set new all-time records
Date	Kind	Detail
1946-01-12	Record daily snowfall	Record daily snowfall 96.5 cm (38.0 in)
1947-01-29	Record low maximum temperature	Record low maximum temperature -19.4 C (-2.9 F)
1947-01-31	Record low maximum temperature	Record low maximum temperature -20.6 C (-5.1 F)
1947-01-31	Record low minimum temperature	Record low minimum temperature -24.4 C (-11.9 F)
1950-01-01	Record low maximum temperature	Record low maximum temperature -21.7 C (-7.1 F)
1950-01-01	Record low minimum temperature	Record low minimum temperature -27.8 C (-18.0 F)
1951-10-27	Record daily precipitation	Record daily precipitation 126.2 mm (5.0 in)
1954-02-02	Record daily precipitation	Record daily precipitation 142.2 mm (5.6 in)
1955-07-04	Record high minimum temperature	Record high minimum temperature 15.6 C (60.1 F)
1958-06-06	Record high maximum temperature	Record high maximum temperature 34.4 C (93.9 F)
1958-06-20	Record high minimum temperature	Record high minimum temperature 16.7 C (62.1 F)
1958-06-30	Record high minimum temperature	Record high minimum temperature 19.4 C (66.9 F)

Wettest Day of Each Month

Feb: 142.2 mm (5.6 in)

The wettest day on record for each calendar month at Mill Bay. The most was 142.2 mm (5.6 in) on 2 February 1954.

Record daily precipitation for each month at Mill Bay
Month	Record daily precipitation (mm)	Date
Jan	96.5 mm (3.8 in)	12 January 1946
Feb	142.2 mm (5.6 in)	2 February 1954
Mar	109.0 mm (4.3 in)	15 March 1959
Apr	59.7 mm (2.4 in)	13 April 1916
May	43.9 mm (1.7 in)	12 May 1939
Jun	31.0 mm (1.2 in)	4 June 1926
Jul	70.1 mm (2.8 in)	30 July 1932
Aug	61.2 mm (2.4 in)	1 August 1955
Sep	65.5 mm (2.6 in)	21 September 1935
Oct	126.2 mm (5.0 in)	27 October 1951
Nov	115.1 mm (4.5 in)	2 November 1956
Dec	113.5 mm (4.5 in)	4 December 1921

Period of Record Coverage

1915 to 1959

45 years of record at Mill Bay, 1915 to 1959. 1 years have data for under 90 percent of days and are left out of rankings: 1959.

Days with data per year at Mill Bay
Year	Days with data	Share of year	Complete
1915	365	100%	Yes
1916	366	100%	Yes
1917	365	100%	Yes
1918	365	100%	Yes
1919	365	100%	Yes
1920	366	100%	Yes
1921	365	100%	Yes
1922	363	99%	Yes
1923	365	100%	Yes
1924	366	100%	Yes
1925	365	100%	Yes
1926	365	100%	Yes
1927	365	100%	Yes
1928	366	100%	Yes
1929	365	100%	Yes
1930	365	100%	Yes
1931	365	100%	Yes
1932	366	100%	Yes
1933	365	100%	Yes
1934	365	100%	Yes
1935	365	100%	Yes
1936	366	100%	Yes
1937	365	100%	Yes
1938	364	100%	Yes
1939	365	100%	Yes
1940	365	100%	Yes
1941	365	100%	Yes
1942	356	98%	Yes
1943	365	100%	Yes
1944	366	100%	Yes
1945	365	100%	Yes
1946	365	100%	Yes
1947	363	99%	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	364	100%	Yes
1958	365	100%	Yes
1959	90	25%	No

Latest Records

Latest records at Mill Bay
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
21 March 1959	Mill Bay, CA	daily snowfall	26.7 cm (10.5 in)	3.3 cm (1.3 in)	10 years	9 of 100 (Routine)
19 March 1959	Mill Bay, CA	daily snowfall	10.2 cm (4.0 in)	4.4 cm (1.7 in)	10 years	10 of 100 (Routine)
16 March 1959	Mill Bay, CA	daily rain	69.3 mm (2.7 in)	44.4 mm (1.7 in)	18 years	49 of 100 (Notable)
15 March 1959	Mill Bay, CA	monthly rain	109.0 mm (4.3 in)	13.7 mm (0.5 in)	8 years	28 of 100 (Routine)
1 March 1959	Mill Bay, CA	daily rain	28.7 mm (1.1 in)	4.6 mm (0.18 in)	29 years	16 of 100 (Routine)
11 February 1959	Mill Bay, CA	daily snowfall	44.5 cm (17.5 in)	14.8 cm (5.8 in)	3 years	15 of 100 (Routine)
11 February 1959	Mill Bay, CA	daily rain	44.5 mm (1.8 in)	2.3 mm (0.09 in)	16 years	9 of 100 (Routine)
11 February 1959	Mill Bay, CA	daily low max (Tie)	-7.8 C (18.0 F)	tie	36 years	3 of 100 (Routine)
1 February 1959	Mill Bay, CA	daily high max	9.4 C (48.9 F)	0.5 C (0.9 F)	19 years	10 of 100 (Routine)
5 January 1959	Mill Bay, CA	daily low min	-21.1 C (-6.0 F)	1.7 C (3.1 F)	8 years	8 of 100 (Routine)
4 January 1959	Mill Bay, CA	daily low min (Tie)	-20.0 C (-4.0 F)	tie	8 years	1 of 100 (Routine)
3 January 1959	Mill Bay, CA	daily low max (Tie)	-18.9 C (-2.0 F)	tie	8 years	1 of 100 (Routine)
3 January 1959	Mill Bay, CA	daily low min (Tie)	-20.6 C (-5.1 F)	tie	8 years	1 of 100 (Routine)
30 December 1958	Mill Bay, CA	daily high max	8.3 C (46.9 F)	1.6 C (2.9 F)	28 years	15 of 100 (Routine)
30 December 1958	Mill Bay, CA	daily rain	58.2 mm (2.3 in)	10.4 mm (0.4 in)	0 years	10 of 100 (Routine)
16 November 1958	Mill Bay, CA	daily snowfall	40.1 cm (15.8 in)	29.9 cm (11.8 in)	28 years	44 of 100 (Notable)
28 October 1958	Mill Bay, CA	daily rain	80.8 mm (3.2 in)	45.5 mm (1.8 in)	8 years	37 of 100 (Notable)
11 October 1958	Mill Bay, CA	daily low max	3.9 C (39.0 F)	2.8 C (5.0 F)	39 years	23 of 100 (Routine)
9 October 1958	Mill Bay, CA	daily low max (Tie)	5.6 C (42.1 F)	tie	39 years	3 of 100 (Routine)
1 October 1958	Mill Bay, CA	daily high min (Tie)	10.6 C (51.1 F)	tie	25 years	2 of 100 (Routine)

Climate Trend

40 complete years, 1915 to 1958

One stripe for each of 40 complete years at Mill Bay, 1915 to 1958. Blue stripes are years cooler than the station's own mean of 6.5 C (43.7 F); red stripes are warmer. The coolest year was 1916, at 4.7 C (40.5 F), and the warmest was 1926, at 8.4 C (47.1 F). The strongest colour marks a difference of 1.9 C (3.4 F).

Annual mean temperature at Mill Bay as warming stripes, 1915 to 1958
Year	Annual mean temperature	Difference from the station mean
1915	7.5 C	+1.00 C
1916	4.7 C	-1.78 C
1917	5.1 C	-1.46 C
1918	5.7 C	-0.80 C
1919	5.3 C	-1.24 C
1920	5.7 C	-0.79 C
1921	5.8 C	-0.70 C
1922	6.0 C	-0.50 C
1923	7.4 C	+0.86 C
1924	6.6 C	+0.13 C
1925	6.0 C	-0.55 C
1926	8.4 C	+1.88 C
1927	5.7 C	-0.80 C
1928	6.9 C	+0.42 C
1929	6.8 C	+0.25 C
1930	6.2 C	-0.32 C
1931	7.1 C	+0.61 C
1932	5.7 C	-0.77 C
1933	5.3 C	-1.26 C
1934	7.3 C	+0.75 C
1935	6.3 C	-0.17 C
1937	6.4 C	-0.16 C
1938	7.0 C	+0.51 C
1939	6.5 C	+0.02 C
1940	7.6 C	+1.09 C
1941	7.8 C	+1.24 C
1943	6.7 C	+0.21 C
1944	7.9 C	+1.42 C
1945	6.3 C	-0.18 C
1946	6.6 C	+0.08 C
1947	6.9 C	+0.40 C
1949	5.9 C	-0.59 C
1951	6.0 C	-0.50 C
1952	7.0 C	+0.44 C
1953	7.6 C	+1.05 C
1954	6.5 C	-0.01 C
1955	4.8 C	-1.68 C
1956	6.1 C	-0.39 C
1957	7.0 C	+0.50 C
1958	8.3 C	+1.82 C

The fitted trend in annual mean temperature here over 1915 to 1958 is 0.20 C (-0.01 to 0.42) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.37 F (-0.02 to 0.76) per decade. The slope is a straight line fitted to 40 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Mill Bay
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.20 C (-0.01 to 0.42) per decade	0.37 F (-0.02 to 0.76) per decade	1915 to 1958	40	Not clearly different from zero
Mean daily maximum	0.21 C (-0.01 to 0.43) per decade	0.38 F (-0.02 to 0.78) per decade	1915 to 1958	40	Not clearly different from zero
Mean daily minimum	0.20 C (-0.03 to 0.43) per decade	0.4 F (-0.1 to 0.8) per decade	1915 to 1958	40	Not 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

1915 to 1959

Yearly extremes at Mill Bay: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	34.4 C (93.9 F)	1958	29.4 C (84.9 F)	45
Coldest night (TNn)	-27.8 C (-18.0 F)	1950	-17.8 C (0.0 F)	45
Wettest day (Rx1day)	142.2 mm (5.6 in)	1954	77.2 mm (3.0 in)	45
Wettest five days (Rx5day)	306.4 mm (12.1 in)	1935	159.5 mm (6.3 in)	45
Longest dry spell (CDD)	28 days	1927	17 days	45

Hottest day (TXx)

The hottest day of the year at Mill Bay, 1915 to 1959. The record is 34.4 C (93.9 F) in 1958, marked on the chart; the median year is 29.4 C (84.9 F).

Hottest day (TXx) at Mill Bay by year
Year	Hottest day (TXx)
1915	30.0 C (86.0 F)
1916	27.8 C (82.0 F)
1917	24.4 C (75.9 F)
1918	28.9 C (84.0 F)
1919	26.1 C (79.0 F)
1920	27.2 C (81.0 F)
1921	25.0 C (77.0 F)
1922	27.8 C (82.0 F)
1923	30.6 C (87.1 F)
1924	31.1 C (88.0 F)
1925	31.1 C (88.0 F)
1926	29.4 C (84.9 F)
1927	31.1 C (88.0 F)
1928	28.3 C (82.9 F)
1929	30.0 C (86.0 F)
1930	27.8 C (82.0 F)
1931	26.1 C (79.0 F)
1932	28.3 C (82.9 F)
1933	28.3 C (82.9 F)
1934	31.7 C (89.1 F)
1935	26.7 C (80.1 F)
1936	30.6 C (87.1 F)
1937	32.2 C (90.0 F)
1938	30.0 C (86.0 F)
1939	26.1 C (79.0 F)
1940	30.6 C (87.1 F)
1941	30.0 C (86.0 F)
1942	30.0 C (86.0 F)
1943	25.6 C (78.1 F)
1944	28.3 C (82.9 F)
1945	28.3 C (82.9 F)
1946	30.0 C (86.0 F)
1947	30.6 C (87.1 F)
1948	30.6 C (87.1 F)
1949	29.4 C (84.9 F)
1950	30.0 C (86.0 F)
1951	28.9 C (84.0 F)
1952	32.2 C (90.0 F)
1953	27.8 C (82.0 F)
1954	27.8 C (82.0 F)
1955	28.3 C (82.9 F)
1956	31.1 C (88.0 F)
1957	30.0 C (86.0 F)
1958	34.4 C (93.9 F)
1959	11.7 C (53.1 F)

Coldest night (TNn)

The coldest night of the year at Mill Bay, 1915 to 1959. The record is -27.8 C (-18.0 F) in 1950, marked on the chart; the median year is -17.8 C (0.0 F).

Coldest night (TNn) at Mill Bay by year
Year	Coldest night (TNn)
1915	-8.3 C (17.1 F)
1916	-23.3 C (-9.9 F)
1917	-23.9 C (-11.0 F)
1918	-13.3 C (8.1 F)
1919	-19.4 C (-2.9 F)
1920	-20.6 C (-5.1 F)
1921	-15.6 C (3.9 F)
1922	-17.8 C (0.0 F)
1923	-16.7 C (1.9 F)
1924	-18.9 C (-2.0 F)
1925	-15.0 C (5.0 F)
1926	-11.7 C (10.9 F)
1927	-18.3 C (-0.9 F)
1928	-15.6 C (3.9 F)
1929	-17.2 C (1.0 F)
1930	-17.2 C (1.0 F)
1931	-11.7 C (10.9 F)
1932	-17.2 C (1.0 F)
1933	-22.2 C (-8.0 F)
1934	-17.8 C (0.0 F)
1935	-20.0 C (-4.0 F)
1936	-18.9 C (-2.0 F)
1937	-17.8 C (0.0 F)
1938	-15.0 C (5.0 F)
1939	-16.1 C (3.0 F)
1940	-10.0 C (14.0 F)
1941	-14.4 C (6.1 F)
1942	-13.9 C (7.0 F)
1943	-19.4 C (-2.9 F)
1944	-11.7 C (10.9 F)
1945	-12.2 C (10.0 F)
1946	-11.7 C (10.9 F)
1947	-24.4 C (-11.9 F)
1948	-22.8 C (-9.0 F)
1949	-22.8 C (-9.0 F)
1950	-27.8 C (-18.0 F)
1951	-20.0 C (-4.0 F)
1952	-19.4 C (-2.9 F)
1953	-20.6 C (-5.1 F)
1954	-21.1 C (-6.0 F)
1955	-15.6 C (3.9 F)
1956	-18.9 C (-2.0 F)
1957	-17.8 C (0.0 F)
1958	-13.3 C (8.1 F)
1959	-21.1 C (-6.0 F)

Wettest day (Rx1day)

The wettest day of the year at Mill Bay, 1915 to 1959. The record is 142.2 mm (5.6 in) in 1954, marked on the chart; the median year is 77.2 mm (3.0 in).

Wettest day (Rx1day) at Mill Bay by year
Year	Wettest day (Rx1day)
1915	87.9 mm (3.5 in)
1916	71.1 mm (2.8 in)
1917	82.8 mm (3.3 in)
1918	61.0 mm (2.4 in)
1919	83.3 mm (3.3 in)
1920	50.8 mm (2.0 in)
1921	113.5 mm (4.5 in)
1922	64.5 mm (2.5 in)
1923	77.2 mm (3.0 in)
1924	66.0 mm (2.6 in)
1925	102.9 mm (4.1 in)
1926	95.8 mm (3.8 in)
1927	47.0 mm (1.9 in)
1928	85.1 mm (3.4 in)
1929	79.0 mm (3.1 in)
1930	60.2 mm (2.4 in)
1931	45.7 mm (1.8 in)
1932	71.1 mm (2.8 in)
1933	99.1 mm (3.9 in)
1934	63.5 mm (2.5 in)
1935	92.2 mm (3.6 in)
1936	63.5 mm (2.5 in)
1937	55.6 mm (2.2 in)
1938	67.3 mm (2.6 in)
1939	78.5 mm (3.1 in)
1940	52.3 mm (2.1 in)
1941	57.9 mm (2.3 in)
1942	59.2 mm (2.3 in)
1943	68.6 mm (2.7 in)
1944	49.5 mm (1.9 in)
1945	60.5 mm (2.4 in)
1946	96.5 mm (3.8 in)
1947	86.4 mm (3.4 in)
1948	59.7 mm (2.4 in)
1949	83.8 mm (3.3 in)
1950	69.9 mm (2.8 in)
1951	126.2 mm (5.0 in)
1952	68.1 mm (2.7 in)
1953	82.6 mm (3.3 in)
1954	142.2 mm (5.6 in)
1955	84.6 mm (3.3 in)
1956	115.1 mm (4.5 in)
1957	112.0 mm (4.4 in)
1958	80.8 mm (3.2 in)
1959	109.0 mm (4.3 in)

Wettest five days (Rx5day)

The wettest five days of the year at Mill Bay, 1915 to 1959. The record is 306.4 mm (12.1 in) in 1935, marked on the chart; the median year is 159.5 mm (6.3 in).

Wettest five days (Rx5day) at Mill Bay by year
Year	Wettest five days (Rx5day)
1915	199.7 mm (7.9 in)
1916	145.8 mm (5.7 in)
1917	223.6 mm (8.8 in)
1918	159.3 mm (6.3 in)
1919	132.9 mm (5.2 in)
1920	110.8 mm (4.4 in)
1921	254.0 mm (10.0 in)
1922	139.7 mm (5.5 in)
1923	202.0 mm (8.0 in)
1924	106.3 mm (4.2 in)
1925	252.1 mm (9.9 in)
1926	233.7 mm (9.2 in)
1927	129.4 mm (5.1 in)
1928	159.5 mm (6.3 in)
1929	179.8 mm (7.1 in)
1930	155.9 mm (6.1 in)
1931	118.4 mm (4.7 in)
1932	191.8 mm (7.6 in)
1933	271.0 mm (10.7 in)
1934	156.6 mm (6.2 in)
1935	306.4 mm (12.1 in)
1936	165.8 mm (6.5 in)
1937	119.1 mm (4.7 in)
1938	159.8 mm (6.3 in)
1939	124.0 mm (4.9 in)
1940	108.2 mm (4.3 in)
1941	131.4 mm (5.2 in)
1942	170.8 mm (6.7 in)
1943	192.5 mm (7.6 in)
1944	108.3 mm (4.3 in)
1945	132.8 mm (5.2 in)
1946	205.5 mm (8.1 in)
1947	215.5 mm (8.5 in)
1948	146.1 mm (5.8 in)
1949	184.2 mm (7.3 in)
1950	154.7 mm (6.1 in)
1951	145.5 mm (5.7 in)
1952	170.9 mm (6.7 in)
1953	147.6 mm (5.8 in)
1954	228.0 mm (9.0 in)
1955	148.3 mm (5.8 in)
1956	212.5 mm (8.4 in)
1957	250.4 mm (9.9 in)
1958	147.6 mm (5.8 in)
1959	215.7 mm (8.5 in)

Longest dry spell (CDD)

The longest dry spell of the year at Mill Bay, 1915 to 1959. The record is 28 days in 1927, marked on the chart; the median year is 17 days.

Longest dry spell (CDD) at Mill Bay by year
Year	Longest dry spell (CDD)
1915	14 days
1916	22 days
1917	13 days
1918	11 days
1919	14 days
1920	24 days
1921	17 days
1922	13 days
1923	17 days
1924	21 days
1925	22 days
1926	14 days
1927	28 days
1928	22 days
1929	19 days
1930	27 days
1931	8 days
1932	21 days
1933	12 days
1934	15 days
1935	16 days
1936	15 days
1937	14 days
1938	20 days
1939	9 days
1940	13 days
1941	24 days
1942	18 days
1943	18 days
1944	13 days
1945	21 days
1946	19 days
1947	19 days
1948	12 days
1949	21 days
1950	15 days
1951	19 days
1952	27 days
1953	14 days
1954	14 days
1955	10 days
1956	11 days
1957	22 days
1958	24 days
1959	9 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

40 years with a frost

Across 40 years with a frost, the median last spring frost at Mill Bay falls on 1 May and the median first autumn frost on 2 November, which leaves a median of 180 days between them.

Fitted over all years, the growing season changes by +4.8 days per decade at this station.

Frost dates and growing season at Mill Bay
Measure	Median, all years	Earliest period	Recent period (1925 to 1958)	Recent against earliest	Fitted trend
Last spring frost	1 May	n/a	30 April	n/a	-1.8 days per decade
First autumn frost	2 November	n/a	29 October	n/a	+2.9 days per decade
Growing days	180 days	n/a	182 days	n/a	+4.8 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

44 years, 1915 to 1958

A day with at least 73.9 mm (2.9 in) of rain is expected about once in 2 years. A day with at least 149.2 mm (5.9 in) of rain is expected about once in 100 years.

Rainfall return levels at Mill Bay: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	73.9 mm (2.9 in)
5 years	93.8 mm (3.7 in)
10 years	107.0 mm (4.2 in)
25 years	123.9 mm (4.9 in)
50 years	136.6 mm (5.4 in)	Longer than the 44 years of record
100 years	149.2 mm (5.9 in)	Longer than the 44 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, 44 years of values from 1915 to 1958.

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: 142.2 mm (5.6 in) in 1954; 126.2 mm (5.0 in) in 1951; 115.1 mm (4.5 in) in 1956.

Station Changes

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

Download the Data

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