Chestnut Hill Weather Records (USC00191447)

Record envelope, standing records and threshold days for Chestnut Hill (USC00191447), Massachusetts, United States, with 94 years of record.

Key Facts for Chestnut Hill

Chestnut Hill (USC00191447) is a weather station in Massachusetts, United States at 42.33 latitude and -71.15 longitude, 37 m (121 ft) above sea level.
The station reports from 1893 to 1986, 94 years of record.
1,464 records set at Chestnut Hill still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Chestnut Hill set a daily record high minimum temperature of 16.7 C (62.1 F) on 30 April 1986.

About the Station

Location: Massachusetts, United States, 42.33 latitude, -71.15 longitude.
Elevation: 37 m (121 ft).
Period of record: 1893 to 1986, 94 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.

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 Chestnut Hill. 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 Chestnut Hill, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	21.1 C (70.0 F)	-28.3 C (-18.9 F)	n/a	n/a
Feb	20.6 C (69.1 F)	-28.3 C (-18.9 F)	n/a	n/a
Mar	29.4 C (84.9 F)	-23.3 C (-9.9 F)	n/a	n/a
Apr	33.3 C (91.9 F)	-12.8 C (9.0 F)	n/a	n/a
May	35.6 C (96.1 F)	-6.1 C (21.0 F)	n/a	n/a
Jun	37.8 C (100.0 F)	1.7 C (35.1 F)	n/a	n/a
Jul	41.1 C (106.0 F)	4.4 C (39.9 F)	n/a	n/a
Aug	40.0 C (104.0 F)	2.2 C (36.0 F)	n/a	n/a
Sep	37.8 C (100.0 F)	-3.9 C (25.0 F)	n/a	n/a
Oct	32.8 C (91.0 F)	-7.2 C (19.0 F)	n/a	n/a
Nov	28.3 C (82.9 F)	-13.9 C (7.0 F)	n/a	n/a
Dec	20.0 C (68.0 F)	-25.6 C (-14.1 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Chestnut Hill still stand. 1986 holds the most, with 43.

Standing records at Chestnut Hill by the year they were set
Year set	Standing records
1893	11
1894	24
1895	24
1896	27
1897	17
1898	17
1899	22
1900	18
1901	14
1902	11
1903	22
1904	22
1905	19
1906	19
1907	18
1908	16
1909	12
1910	12
1911	23
1912	12
1913	12
1914	26
1915	11
1916	21
1917	14
1918	32
1919	33
1920	23
1921	14
1922	10
1923	23
1924	14
1925	18
1926	17
1927	8
1928	8
1929	22
1930	14
1931	9
1932	19
1933	17
1934	17
1935	13
1936	10
1937	18
1938	15
1939	10
1940	11
1941	8
1942	14
1943	9
1944	13
1945	16
1946	18
1947	12
1948	15
1949	20
1950	18
1951	14
1952	13
1953	18
1954	19
1955	11
1956	8
1957	20
1958	5
1959	12
1960	4
1961	7
1962	15
1963	14
1964	10
1965	13
1966	12
1967	9
1968	7
1969	5
1970	10
1971	10
1972	7
1973	5
1974	20
1975	13
1976	18
1977	13
1978	5
1979	32
1980	8
1981	8
1982	22
1983	16
1984	42
1985	14
1986	43

All-Time Record Progression

2 new records

2 all-time records were set at Chestnut Hill between 28 June 1941 and 10 February 1969. Each dot is a new record.

When Chestnut Hill set new all-time records
Date	Kind	Detail
1941-06-28	Record high minimum temperature	Record high minimum temperature 29.4 C (84.9 F)
1969-02-10	Record daily snowfall	Record daily snowfall 50.8 cm (20.0 in)

Wettest Day of Each Month

Oct: 191.8 mm (7.6 in)

The wettest day on record for each calendar month at Chestnut Hill. The most was 191.8 mm (7.6 in) on 13 October 1895.

Record daily precipitation for each month at Chestnut Hill
Month	Record daily precipitation (mm)	Date
Jan	75.7 mm (3.0 in)	9 January 1935
Feb	88.4 mm (3.5 in)	22 February 1898
Mar	78.7 mm (3.1 in)	19 March 1968
Apr	136.4 mm (5.4 in)	30 April 1904
May	187.2 mm (7.4 in)	18 May 1905
Jun	111.5 mm (4.4 in)	9 June 1931
Jul	87.4 mm (3.4 in)	28 July 1911
Aug	165.1 mm (6.5 in)	20 August 1955
Sep	151.1 mm (5.9 in)	12 September 1954
Oct	191.8 mm (7.6 in)	13 October 1895
Nov	103.6 mm (4.1 in)	5 November 1955
Dec	134.6 mm (5.3 in)	27 December 1969

Period of Record Coverage

1893 to 1986

94 years of record at Chestnut Hill, 1893 to 1986. 8 years have data for under 90 percent of days and are left out of rankings: 1936, 1968, 1974, 1976, 1978, 1980, 1985, 1986.

Days with data per year at Chestnut Hill
Year	Days with data	Share of year	Complete
1893	365	100%	Yes
1894	365	100%	Yes
1895	364	100%	Yes
1896	364	99%	Yes
1897	365	100%	Yes
1898	364	100%	Yes
1899	365	100%	Yes
1900	362	99%	Yes
1901	354	97%	Yes
1902	361	99%	Yes
1903	363	99%	Yes
1904	365	100%	Yes
1905	360	99%	Yes
1906	365	100%	Yes
1907	364	100%	Yes
1908	365	100%	Yes
1909	364	100%	Yes
1910	363	99%	Yes
1911	365	100%	Yes
1912	365	100%	Yes
1913	364	100%	Yes
1914	364	100%	Yes
1915	364	100%	Yes
1916	364	99%	Yes
1917	363	99%	Yes
1918	361	99%	Yes
1919	364	100%	Yes
1920	330	90%	Yes
1921	363	99%	Yes
1922	361	99%	Yes
1923	358	98%	Yes
1924	364	99%	Yes
1925	362	99%	Yes
1926	365	100%	Yes
1927	365	100%	Yes
1928	366	100%	Yes
1929	354	97%	Yes
1930	360	99%	Yes
1931	358	98%	Yes
1932	354	97%	Yes
1933	356	98%	Yes
1934	365	100%	Yes
1935	362	99%	Yes
1936	315	86%	No
1937	365	100%	Yes
1938	365	100%	Yes
1939	364	100%	Yes
1940	363	99%	Yes
1941	365	100%	Yes
1942	364	100%	Yes
1943	363	99%	Yes
1944	365	100%	Yes
1945	365	100%	Yes
1946	365	100%	Yes
1947	364	100%	Yes
1948	366	100%	Yes
1949	364	100%	Yes
1950	364	100%	Yes
1951	363	99%	Yes
1952	366	100%	Yes
1953	365	100%	Yes
1954	356	98%	Yes
1955	359	98%	Yes
1956	357	98%	Yes
1957	338	93%	Yes
1958	348	95%	Yes
1959	342	94%	Yes
1960	343	94%	Yes
1961	337	92%	Yes
1962	339	93%	Yes
1963	354	97%	Yes
1964	337	92%	Yes
1965	331	91%	Yes
1966	334	92%	Yes
1967	331	91%	Yes
1968	322	88%	No
1969	329	90%	Yes
1970	360	99%	Yes
1971	358	98%	Yes
1972	339	93%	Yes
1973	340	93%	Yes
1974	317	87%	No
1975	355	97%	Yes
1976	321	88%	No
1977	357	98%	Yes
1978	324	89%	No
1979	363	99%	Yes
1980	322	88%	No
1981	338	93%	Yes
1982	347	95%	Yes
1983	342	94%	Yes
1984	349	95%	Yes
1985	326	89%	No
1986	85	23%	No

Latest Records

Latest records at Chestnut Hill
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
30 April 1986	Chestnut Hill, US	daily high min	16.7 C (62.1 F)	1.7 C (3.1 F)	79 years	36 of 100 (Notable)
29 April 1986	Chestnut Hill, US	daily high min	16.1 C (61.0 F)	3.9 C (7.0 F)	16 years	23 of 100 (Routine)
28 April 1986	Chestnut Hill, US	daily high min	17.8 C (64.0 F)	2.2 C (4.0 F)	51 years	29 of 100 (Routine)
27 April 1986	Chestnut Hill, US	daily high min (Tie)	15.6 C (60.1 F)	tie	7 years	2 of 100 (Routine)
26 April 1986	Chestnut Hill, US	daily high min (Tie)	18.3 C (64.9 F)	tie	43 years	5 of 100 (Routine)
25 April 1986	Chestnut Hill, US	daily high min	17.2 C (63.0 F)	5.5 C (9.9 F)	72 years	43 of 100 (Notable)
24 April 1986	Chestnut Hill, US	daily high min	14.4 C (57.9 F)	2.2 C (4.0 F)	28 years	22 of 100 (Routine)
22 April 1986	Chestnut Hill, US	monthly high min	18.9 C (66.0 F)	0.6 C (1.1 F)	42 years	32 of 100 (Routine)
21 April 1986	Chestnut Hill, US	daily high min	17.8 C (64.0 F)	1.7 C (3.1 F)	63 years	31 of 100 (Routine)
11 April 1986	Chestnut Hill, US	daily high min	11.1 C (52.0 F)	0.5 C (0.9 F)	31 years	19 of 100 (Routine)
10 April 1986	Chestnut Hill, US	daily high min	13.9 C (57.0 F)	4.5 C (8.1 F)	40 years	32 of 100 (Routine)
9 April 1986	Chestnut Hill, US	daily high min	14.4 C (57.9 F)	3.3 C (5.9 F)	90 years	44 of 100 (Notable)
8 April 1986	Chestnut Hill, US	daily high min	13.9 C (57.0 F)	0.6 C (1.1 F)	56 years	27 of 100 (Routine)
6 April 1986	Chestnut Hill, US	daily high min	12.8 C (55.0 F)	1.7 C (3.1 F)	73 years	35 of 100 (Notable)
4 April 1986	Chestnut Hill, US	daily high min	13.3 C (55.9 F)	3.9 C (7.0 F)	36 years	28 of 100 (Routine)
3 April 1986	Chestnut Hill, US	daily high min	15.6 C (60.1 F)	4.5 C (8.1 F)	19 years	25 of 100 (Routine)
3 April 1986	Chestnut Hill, US	daily high max	21.1 C (70.0 F)	1.1 C (2.0 F)	15 years	14 of 100 (Routine)
2 April 1986	Chestnut Hill, US	daily high min	17.2 C (63.0 F)	4.4 C (7.9 F)	40 years	31 of 100 (Routine)
1 April 1986	Chestnut Hill, US	daily high max	26.7 C (80.1 F)	1.7 C (3.1 F)	68 years	31 of 100 (Routine)
1 April 1986	Chestnut Hill, US	monthly high min (Tie)	18.3 C (64.9 F)	tie	42 years	7 of 100 (Routine)

Climate Trend

82 complete years, 1893 to 1985

One stripe for each of 82 complete years at Chestnut Hill, 1893 to 1985. Blue stripes are years cooler than the station's own mean of 10.1 C (50.2 F); red stripes are warmer. The coolest year was 1904, at 8.0 C (46.5 F), and the warmest was 1949, at 12.4 C (54.2 F). The strongest colour marks a difference of 2.3 C (4.1 F).

Annual mean temperature at Chestnut Hill as warming stripes, 1893 to 1985
Year	Annual mean temperature	Difference from the station mean
1893	8.9 C	-1.23 C
1894	10.2 C	+0.15 C
1895	9.6 C	-0.52 C
1896	9.5 C	-0.59 C
1897	9.8 C	-0.33 C
1898	10.1 C	+0.03 C
1899	9.8 C	-0.30 C
1900	10.1 C	+0.05 C
1901	9.3 C	-0.83 C
1902	9.7 C	-0.36 C
1903	9.5 C	-0.63 C
1904	8.0 C	-2.05 C
1905	9.1 C	-0.99 C
1906	10.0 C	-0.08 C
1907	9.2 C	-0.91 C
1908	10.5 C	+0.38 C
1909	10.1 C	-0.01 C
1910	10.2 C	+0.10 C
1911	10.1 C	+0.05 C
1912	9.5 C	-0.54 C
1913	10.9 C	+0.79 C
1914	9.3 C	-0.77 C
1915	10.1 C	+0.02 C
1916	9.3 C	-0.74 C
1917	8.8 C	-1.33 C
1918	8.6 C	-1.47 C
1919	8.4 C	-1.64 C
1921	11.7 C	+1.57 C
1922	10.2 C	+0.12 C
1923	8.8 C	-1.27 C
1924	9.0 C	-1.11 C
1925	9.9 C	-0.22 C
1926	8.6 C	-1.48 C
1928	10.2 C	+0.14 C
1929	9.6 C	-0.45 C
1930	10.3 C	+0.17 C
1931	10.3 C	+0.18 C
1932	9.8 C	-0.31 C
1933	10.3 C	+0.19 C
1934	10.2 C	+0.16 C
1935	10.1 C	0.00 C
1937	11.3 C	+1.17 C
1938	11.3 C	+1.26 C
1939	10.4 C	+0.32 C
1940	9.7 C	-0.42 C
1941	11.3 C	+1.19 C
1942	11.2 C	+1.16 C
1943	10.6 C	+0.52 C
1944	11.1 C	+1.02 C
1945	10.9 C	+0.81 C
1946	11.3 C	+1.22 C
1947	11.0 C	+0.91 C
1948	10.6 C	+0.52 C
1949	12.4 C	+2.27 C
1951	11.4 C	+1.33 C
1952	11.5 C	+1.44 C
1953	12.2 C	+2.16 C
1954	11.1 C	+1.06 C
1955	11.0 C	+0.89 C
1956	10.4 C	+0.34 C
1957	11.7 C	+1.58 C
1959	10.6 C	+0.50 C
1960	10.2 C	+0.14 C
1961	10.4 C	+0.28 C
1962	9.4 C	-0.67 C
1963	10.3 C	+0.18 C
1964	10.2 C	+0.10 C
1965	10.4 C	+0.31 C
1966	10.4 C	+0.36 C
1967	9.7 C	-0.38 C
1968	10.1 C	+0.02 C
1969	10.4 C	+0.28 C
1970	9.1 C	-1.02 C
1971	9.7 C	-0.40 C
1972	8.7 C	-1.38 C
1975	10.1 C	0.00 C
1977	9.9 C	-0.20 C
1979	9.6 C	-0.49 C
1982	8.9 C	-1.17 C
1983	9.8 C	-0.33 C
1984	8.6 C	-1.44 C
1985	11.0 C	+0.91 C

The annual mean temperature here has risen by 0.08 C (0.01 to 0.16) per decade over 1893 to 1985. In Fahrenheit: 0.15 F (0.02 to 0.28) per decade. The slope is a straight line fitted to 82 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Chestnut Hill
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.08 C (0.01 to 0.16) per decade	0.15 F (0.02 to 0.28) per decade	1893 to 1985	82	Rise
Mean daily maximum	0.02 C (-0.05 to 0.09) per decade	0.03 F (-0.10 to 0.16) per decade	1893 to 1985	82	Not clearly different from zero
Mean daily minimum	0.1 C (0.1 to 0.2) per decade	0.3 F (0.1 to 0.4) per decade	1893 to 1985	82	Rise

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 1986

Yearly extremes at Chestnut Hill: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	41.1 C (106.0 F)	1894	35.6 C (96.1 F)	94
Coldest night (TNn)	-28.3 C (-18.9 F)	1920	-19.4 C (-2.9 F)	94
Wettest day (Rx1day)	191.8 mm (7.6 in)	1895	66.0 mm (2.6 in)	94
Wettest five days (Rx5day)	330.7 mm (13.0 in)	1955	98.7 mm (3.9 in)	94
Longest dry spell (CDD)	45 days	1924	17 days	94

Hottest day (TXx)

The hottest day of the year at Chestnut Hill, 1893 to 1986. The record is 41.1 C (106.0 F) in 1894, marked on the chart; the median year is 35.6 C (96.1 F).

Hottest day (TXx) at Chestnut Hill by year
Year	Hottest day (TXx)
1893	34.4 C (93.9 F)
1894	41.1 C (106.0 F)
1895	35.6 C (96.1 F)
1896	36.1 C (97.0 F)
1897	34.4 C (93.9 F)
1898	36.7 C (98.1 F)
1899	35.6 C (96.1 F)
1900	36.7 C (98.1 F)
1901	37.2 C (99.0 F)
1902	33.3 C (91.9 F)
1903	35.0 C (95.0 F)
1904	34.4 C (93.9 F)
1905	35.6 C (96.1 F)
1906	34.4 C (93.9 F)
1907	37.2 C (99.0 F)
1908	38.3 C (100.9 F)
1909	36.7 C (98.1 F)
1910	35.0 C (95.0 F)
1911	39.4 C (102.9 F)
1912	37.2 C (99.0 F)
1913	36.7 C (98.1 F)
1914	35.0 C (95.0 F)
1915	34.4 C (93.9 F)
1916	35.0 C (95.0 F)
1917	37.2 C (99.0 F)
1918	35.6 C (96.1 F)
1919	37.8 C (100.0 F)
1920	33.3 C (91.9 F)
1921	34.4 C (93.9 F)
1922	33.9 C (93.0 F)
1923	35.0 C (95.0 F)
1924	36.1 C (97.0 F)
1925	35.6 C (96.1 F)
1926	38.9 C (102.0 F)
1927	35.0 C (95.0 F)
1928	35.6 C (96.1 F)
1929	35.0 C (95.0 F)
1930	35.6 C (96.1 F)
1931	35.6 C (96.1 F)
1932	33.9 C (93.0 F)
1933	37.2 C (99.0 F)
1934	36.1 C (97.0 F)
1935	34.4 C (93.9 F)
1936	35.6 C (96.1 F)
1937	36.7 C (98.1 F)
1938	34.4 C (93.9 F)
1939	35.0 C (95.0 F)
1940	34.4 C (93.9 F)
1941	35.6 C (96.1 F)
1942	33.3 C (91.9 F)
1943	35.6 C (96.1 F)
1944	37.8 C (100.0 F)
1945	35.0 C (95.0 F)
1946	35.0 C (95.0 F)
1947	35.0 C (95.0 F)
1948	36.1 C (97.0 F)
1949	37.8 C (100.0 F)
1950	35.6 C (96.1 F)
1951	33.9 C (93.0 F)
1952	38.3 C (100.9 F)
1953	37.8 C (100.0 F)
1954	35.6 C (96.1 F)
1955	37.2 C (99.0 F)
1956	36.1 C (97.0 F)
1957	35.0 C (95.0 F)
1958	32.8 C (91.0 F)
1959	33.9 C (93.0 F)
1960	32.2 C (90.0 F)
1961	32.8 C (91.0 F)
1962	33.9 C (93.0 F)
1963	35.6 C (96.1 F)
1964	34.4 C (93.9 F)
1965	34.4 C (93.9 F)
1966	34.4 C (93.9 F)
1967	33.3 C (91.9 F)
1968	35.0 C (95.0 F)
1969	34.4 C (93.9 F)
1970	33.3 C (91.9 F)
1971	34.4 C (93.9 F)
1972	35.0 C (95.0 F)
1973	35.6 C (96.1 F)
1974	33.9 C (93.0 F)
1975	38.9 C (102.0 F)
1976	33.9 C (93.0 F)
1977	37.8 C (100.0 F)
1978	37.8 C (100.0 F)
1979	35.0 C (95.0 F)
1980	36.7 C (98.1 F)
1981	35.6 C (96.1 F)
1982	37.2 C (99.0 F)
1983	40.0 C (104.0 F)
1984	37.2 C (99.0 F)
1985	35.6 C (96.1 F)
1986	26.7 C (80.1 F)

Coldest night (TNn)

The coldest night of the year at Chestnut Hill, 1893 to 1986. The record is -28.3 C (-18.9 F) in 1920, marked on the chart; the median year is -19.4 C (-2.9 F).

Coldest night (TNn) at Chestnut Hill by year
Year	Coldest night (TNn)
1893	-21.7 C (-7.1 F)
1894	-23.3 C (-9.9 F)
1895	-22.8 C (-9.0 F)
1896	-25.0 C (-13.0 F)
1897	-18.3 C (-0.9 F)
1898	-22.8 C (-9.0 F)
1899	-23.3 C (-9.9 F)
1900	-21.1 C (-6.0 F)
1901	-21.1 C (-6.0 F)
1902	-23.3 C (-9.9 F)
1903	-21.1 C (-6.0 F)
1904	-27.2 C (-17.0 F)
1905	-19.4 C (-2.9 F)
1906	-18.3 C (-0.9 F)
1907	-23.3 C (-9.9 F)
1908	-19.4 C (-2.9 F)
1909	-18.9 C (-2.0 F)
1910	-21.1 C (-6.0 F)
1911	-18.9 C (-2.0 F)
1912	-22.2 C (-8.0 F)
1913	-17.8 C (0.0 F)
1914	-24.4 C (-11.9 F)
1915	-17.2 C (1.0 F)
1916	-22.2 C (-8.0 F)
1917	-25.6 C (-14.1 F)
1918	-25.6 C (-14.1 F)
1919	-25.6 C (-14.1 F)
1920	-28.3 C (-18.9 F)
1921	-20.0 C (-4.0 F)
1922	-23.9 C (-11.0 F)
1923	-22.8 C (-9.0 F)
1924	-22.8 C (-9.0 F)
1925	-21.1 C (-6.0 F)
1926	-18.3 C (-0.9 F)
1927	-17.2 C (1.0 F)
1928	-18.3 C (-0.9 F)
1929	-20.0 C (-4.0 F)
1930	-19.4 C (-2.9 F)
1931	-17.8 C (0.0 F)
1932	-17.8 C (0.0 F)
1933	-25.0 C (-13.0 F)
1934	-25.6 C (-14.1 F)
1935	-22.2 C (-8.0 F)
1936	-17.2 C (1.0 F)
1937	-10.6 C (12.9 F)
1938	-18.9 C (-2.0 F)
1939	-15.0 C (5.0 F)
1940	-16.1 C (3.0 F)
1941	-15.6 C (3.9 F)
1942	-25.6 C (-14.1 F)
1943	-23.3 C (-9.9 F)
1944	-14.4 C (6.1 F)
1945	-19.4 C (-2.9 F)
1946	-17.2 C (1.0 F)
1947	-15.6 C (3.9 F)
1948	-19.4 C (-2.9 F)
1949	-13.3 C (8.1 F)
1950	-18.3 C (-0.9 F)
1951	-17.8 C (0.0 F)
1952	-17.8 C (0.0 F)
1953	-12.8 C (9.0 F)
1954	-19.4 C (-2.9 F)
1955	-20.6 C (-5.1 F)
1956	-16.1 C (3.0 F)
1957	-25.6 C (-14.1 F)
1958	-16.1 C (3.0 F)
1959	-17.8 C (0.0 F)
1960	-13.9 C (7.0 F)
1961	-17.8 C (0.0 F)
1962	-20.6 C (-5.1 F)
1963	-18.9 C (-2.0 F)
1964	-21.1 C (-6.0 F)
1965	-20.6 C (-5.1 F)
1966	-17.8 C (0.0 F)
1967	-16.7 C (1.9 F)
1968	-21.1 C (-6.0 F)
1969	-15.0 C (5.0 F)
1970	-23.3 C (-9.9 F)
1971	-17.8 C (0.0 F)
1972	-17.8 C (0.0 F)
1973	-18.9 C (-2.0 F)
1974	-20.6 C (-5.1 F)
1975	-16.7 C (1.9 F)
1976	-22.2 C (-8.0 F)
1977	-16.7 C (1.9 F)
1978	-17.8 C (0.0 F)
1979	-21.1 C (-6.0 F)
1980	-17.8 C (0.0 F)
1981	-22.2 C (-8.0 F)
1982	-20.0 C (-4.0 F)
1983	-19.4 C (-2.9 F)
1984	-28.3 C (-18.9 F)
1985	-17.8 C (0.0 F)
1986	-5.6 C (21.9 F)

Wettest day (Rx1day)

The wettest day of the year at Chestnut Hill, 1893 to 1986. The record is 191.8 mm (7.6 in) in 1895, marked on the chart; the median year is 66.0 mm (2.6 in).

Wettest day (Rx1day) at Chestnut Hill by year
Year	Wettest day (Rx1day)
1893	85.3 mm (3.4 in)
1894	46.2 mm (1.8 in)
1895	191.8 mm (7.6 in)
1896	65.3 mm (2.6 in)
1897	63.0 mm (2.5 in)
1898	88.4 mm (3.5 in)
1899	84.8 mm (3.3 in)
1900	74.4 mm (2.9 in)
1901	68.1 mm (2.7 in)
1902	60.2 mm (2.4 in)
1903	71.9 mm (2.8 in)
1904	136.4 mm (5.4 in)
1905	187.2 mm (7.4 in)
1906	98.8 mm (3.9 in)
1907	81.0 mm (3.2 in)
1908	59.9 mm (2.4 in)
1909	77.5 mm (3.1 in)
1910	66.8 mm (2.6 in)
1911	87.4 mm (3.4 in)
1912	83.1 mm (3.3 in)
1913	32.3 mm (1.3 in)
1914	54.6 mm (2.1 in)
1915	106.4 mm (4.2 in)
1916	38.1 mm (1.5 in)
1917	81.3 mm (3.2 in)
1918	56.9 mm (2.2 in)
1919	59.2 mm (2.3 in)
1920	56.1 mm (2.2 in)
1921	77.2 mm (3.0 in)
1922	90.4 mm (3.6 in)
1923	55.9 mm (2.2 in)
1924	133.4 mm (5.3 in)
1925	42.9 mm (1.7 in)
1926	45.5 mm (1.8 in)
1927	66.0 mm (2.6 in)
1928	52.6 mm (2.1 in)
1929	98.8 mm (3.9 in)
1930	54.9 mm (2.2 in)
1931	111.5 mm (4.4 in)
1932	98.8 mm (3.9 in)
1933	92.2 mm (3.6 in)
1934	49.5 mm (1.9 in)
1935	75.7 mm (3.0 in)
1936	91.2 mm (3.6 in)
1937	67.6 mm (2.7 in)
1938	79.0 mm (3.1 in)
1939	66.0 mm (2.6 in)
1940	43.9 mm (1.7 in)
1941	52.6 mm (2.1 in)
1942	47.8 mm (1.9 in)
1943	56.9 mm (2.2 in)
1944	84.8 mm (3.3 in)
1945	62.5 mm (2.5 in)
1946	56.4 mm (2.2 in)
1947	87.9 mm (3.5 in)
1948	42.7 mm (1.7 in)
1949	103.1 mm (4.1 in)
1950	77.5 mm (3.1 in)
1951	46.2 mm (1.8 in)
1952	80.3 mm (3.2 in)
1953	59.7 mm (2.4 in)
1954	151.1 mm (5.9 in)
1955	165.1 mm (6.5 in)
1956	60.7 mm (2.4 in)
1957	42.2 mm (1.7 in)
1958	64.8 mm (2.6 in)
1959	58.4 mm (2.3 in)
1960	64.3 mm (2.5 in)
1961	76.2 mm (3.0 in)
1962	141.0 mm (5.6 in)
1963	76.2 mm (3.0 in)
1964	48.3 mm (1.9 in)
1965	46.2 mm (1.8 in)
1966	53.1 mm (2.1 in)
1967	61.0 mm (2.4 in)
1968	78.7 mm (3.1 in)
1969	134.6 mm (5.3 in)
1970	63.0 mm (2.5 in)
1971	53.3 mm (2.1 in)
1972	62.5 mm (2.5 in)
1973	61.0 mm (2.4 in)
1974	61.2 mm (2.4 in)
1975	58.4 mm (2.3 in)
1976	50.5 mm (2.0 in)
1977	76.2 mm (3.0 in)
1978	63.5 mm (2.5 in)
1979	58.4 mm (2.3 in)
1980	62.5 mm (2.5 in)
1981	66.5 mm (2.6 in)
1982	101.6 mm (4.0 in)
1983	101.6 mm (4.0 in)
1984	76.7 mm (3.0 in)
1985	124.7 mm (4.9 in)
1986	58.4 mm (2.3 in)

Wettest five days (Rx5day)

The wettest five days of the year at Chestnut Hill, 1893 to 1986. The record is 330.7 mm (13.0 in) in 1955, marked on the chart; the median year is 98.7 mm (3.9 in).

Wettest five days (Rx5day) at Chestnut Hill by year
Year	Wettest five days (Rx5day)
1893	97.2 mm (3.8 in)
1894	85.1 mm (3.4 in)
1895	193.1 mm (7.6 in)
1896	104.1 mm (4.1 in)
1897	73.7 mm (2.9 in)
1898	94.0 mm (3.7 in)
1899	88.4 mm (3.5 in)
1900	97.6 mm (3.8 in)
1901	94.5 mm (3.7 in)
1902	65.8 mm (2.6 in)
1903	101.3 mm (4.0 in)
1904	136.4 mm (5.4 in)
1905	138.2 mm (5.4 in)
1906	102.1 mm (4.0 in)
1907	94.7 mm (3.7 in)
1908	87.9 mm (3.5 in)
1909	95.1 mm (3.7 in)
1910	97.0 mm (3.8 in)
1911	114.5 mm (4.5 in)
1912	107.2 mm (4.2 in)
1913	71.1 mm (2.8 in)
1914	67.0 mm (2.6 in)
1915	165.0 mm (6.5 in)
1916	69.1 mm (2.7 in)
1917	94.0 mm (3.7 in)
1918	80.7 mm (3.2 in)
1919	111.5 mm (4.4 in)
1920	79.5 mm (3.1 in)
1921	129.5 mm (5.1 in)
1922	173.0 mm (6.8 in)
1923	68.6 mm (2.7 in)
1924	146.6 mm (5.8 in)
1925	115.6 mm (4.6 in)
1926	77.8 mm (3.1 in)
1927	106.6 mm (4.2 in)
1928	79.2 mm (3.1 in)
1929	136.4 mm (5.4 in)
1930	91.3 mm (3.6 in)
1931	153.2 mm (6.0 in)
1932	171.2 mm (6.7 in)
1933	205.7 mm (8.1 in)
1934	73.6 mm (2.9 in)
1935	123.2 mm (4.9 in)
1936	94.0 mm (3.7 in)
1937	81.0 mm (3.2 in)
1938	172.2 mm (6.8 in)
1939	95.4 mm (3.8 in)
1940	89.1 mm (3.5 in)
1941	54.1 mm (2.1 in)
1942	65.6 mm (2.6 in)
1943	71.9 mm (2.8 in)
1944	142.0 mm (5.6 in)
1945	95.5 mm (3.8 in)
1946	106.4 mm (4.2 in)
1947	121.4 mm (4.8 in)
1948	58.7 mm (2.3 in)
1949	111.7 mm (4.4 in)
1950	84.4 mm (3.3 in)
1951	95.4 mm (3.8 in)
1952	126.0 mm (5.0 in)
1953	127.2 mm (5.0 in)
1954	184.3 mm (7.3 in)
1955	330.7 mm (13.0 in)
1956	150.1 mm (5.9 in)
1957	69.8 mm (2.7 in)
1958	103.1 mm (4.1 in)
1959	89.2 mm (3.5 in)
1960	100.7 mm (4.0 in)
1961	145.8 mm (5.7 in)
1962	218.0 mm (8.6 in)
1963	101.3 mm (4.0 in)
1964	67.1 mm (2.6 in)
1965	60.1 mm (2.4 in)
1966	80.8 mm (3.2 in)
1967	77.5 mm (3.1 in)
1968	160.5 mm (6.3 in)
1969	167.0 mm (6.6 in)
1970	84.0 mm (3.3 in)
1971	99.8 mm (3.9 in)
1972	78.1 mm (3.1 in)
1973	88.6 mm (3.5 in)
1974	67.6 mm (2.7 in)
1975	119.1 mm (4.7 in)
1976	103.8 mm (4.1 in)
1977	86.2 mm (3.4 in)
1978	100.6 mm (4.0 in)
1979	138.9 mm (5.5 in)
1980	67.6 mm (2.7 in)
1981	109.4 mm (4.3 in)
1982	226.1 mm (8.9 in)
1983	264.7 mm (10.4 in)
1984	206.9 mm (8.1 in)
1985	124.7 mm (4.9 in)
1986	76.7 mm (3.0 in)

Longest dry spell (CDD)

The longest dry spell of the year at Chestnut Hill, 1893 to 1986. The record is 45 days in 1924, marked on the chart; the median year is 17 days.

Longest dry spell (CDD) at Chestnut Hill by year
Year	Longest dry spell (CDD)
1893	16 days
1894	18 days
1895	18 days
1896	15 days
1897	15 days
1898	9 days
1899	16 days
1900	18 days
1901	26 days
1902	17 days
1903	17 days
1904	18 days
1905	13 days
1906	12 days
1907	15 days
1908	21 days
1909	13 days
1910	15 days
1911	17 days
1912	19 days
1913	14 days
1914	25 days
1915	36 days
1916	13 days
1917	21 days
1918	19 days
1919	19 days
1920	25 days
1921	18 days
1922	20 days
1923	20 days
1924	45 days
1925	19 days
1926	16 days
1927	15 days
1928	10 days
1929	14 days
1930	29 days
1931	15 days
1932	13 days
1933	12 days
1934	17 days
1935	20 days
1936	22 days
1937	13 days
1938	13 days
1939	26 days
1940	12 days
1941	19 days
1942	14 days
1943	19 days
1944	18 days
1945	13 days
1946	17 days
1947	35 days
1948	12 days
1949	11 days
1950	22 days
1951	12 days
1952	16 days
1953	14 days
1954	15 days
1955	24 days
1956	16 days
1957	19 days
1958	21 days
1959	15 days
1960	17 days
1961	17 days
1962	13 days
1963	24 days
1964	20 days
1965	22 days
1966	14 days
1967	12 days
1968	22 days
1969	22 days
1970	13 days
1971	14 days
1972	25 days
1973	16 days
1974	15 days
1975	21 days
1976	20 days
1977	15 days
1978	16 days
1979	14 days
1980	18 days
1981	17 days
1982	12 days
1983	20 days
1984	19 days
1985	15 days
1986	13 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

82 years with a frost

Across 82 years with a frost, the median last spring frost at Chestnut Hill falls on 25 April and the median first autumn frost on 19 October, which leaves a median of 176 days between them.

In 1948 to 1985 the median growing season was 185 days. That is 16 days more than in 1893 to 1923.

Fitted over all years, the growing season changes by +1.9 days per decade at this station.

Frost dates and growing season at Chestnut Hill
Measure	Median, all years	Earliest period (1893 to 1923)	Recent period (1948 to 1985)	Recent against earliest	Fitted trend
Last spring frost	25 April	29 April	21 April	8 days earlier	-0.9 days per decade
First autumn frost	19 October	15 October	23 October	8 days later	+1.0 days per decade
Growing days	176 days	169 days	185 days	16 days more	+1.9 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

89 years, 1893 to 1985

A day with at least 69.0 mm (2.7 in) of rain is expected about once in 2 years. A day with at least 202.7 mm (8.0 in) of rain is expected about once in 100 years.

Rainfall return levels at Chestnut Hill: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	69.0 mm (2.7 in)
5 years	93.6 mm (3.7 in)
10 years	113.6 mm (4.5 in)
25 years	144.1 mm (5.7 in)
50 years	171.3 mm (6.7 in)
100 years	202.7 mm (8.0 in)	Longer than the 89 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, 89 years of values from 1893 to 1985.

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: 191.8 mm (7.6 in) in 1895; 187.2 mm (7.4 in) in 1905; 165.1 mm (6.5 in) in 1955.

Station Changes

2 suspected

2 changes were suspected in the annual mean temperature of Chestnut Hill, at 1937 and 1959. Each is measured against neighbouring stations.

Relative to 5 neighbouring stations, the station's annual mean temperature from 1937 ran 0.4 C (0.8 F) higher than in the years before (possible change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1959 ran 0.4 C (0.7 F) lower than in the years before (likely change).

Suspected changes in the annual mean temperature at Chestnut Hill, against neighbouring stations
Year	Shift (C)	Shift (F)	Strength	Neighbours
1937	+0.4	+0.8	possible	5
1959	-0.4	-0.7	likely	5

Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.

Download the Data

Data for Chestnut Hill standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Chestnut Hill 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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).