Fort National Weather Records (AGE00147709)

Record envelope, standing records and threshold days for Fort National (AGE00147709), Algeria, with 60 years of record.

Key Facts for Fort National

Fort National (AGE00147709) is a weather station in Algeria at 36.63 latitude and 4.20 longitude, 942 m (3,091 ft) above sea level.
The station reports from 1879 to 1938, 60 years of record.
1,464 records set at Fort National still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
Fort National set a daily record low maximum temperature of 1.0 C (33.8 F) on 27 December 1938.

About the Station

Location: Algeria, 36.63 latitude, 4.20 longitude.
Elevation: 942 m (3,091 ft).
Period of record: 1879 to 1938, 60 years.
Eligible elements: tmax, tmin, prcp.

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 Fort National. 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 Fort National, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	21.0 C (69.8 F)	-5.0 C (23.0 F)	n/a	n/a
Feb	24.0 C (75.2 F)	-7.0 C (19.4 F)	n/a	n/a
Mar	29.0 C (84.2 F)	-5.0 C (23.0 F)	n/a	n/a
Apr	33.0 C (91.4 F)	-4.0 C (24.8 F)	n/a	n/a
May	39.0 C (102.2 F)	0.0 C (32.0 F)	n/a	n/a
Jun	41.0 C (105.8 F)	5.0 C (41.0 F)	n/a	n/a
Jul	45.0 C (113.0 F)	7.0 C (44.6 F)	n/a	n/a
Aug	43.0 C (109.4 F)	10.0 C (50.0 F)	n/a	n/a
Sep	44.0 C (111.2 F)	7.0 C (44.6 F)	n/a	n/a
Oct	38.0 C (100.4 F)	-1.0 C (30.2 F)	n/a	n/a
Nov	28.0 C (82.4 F)	-2.0 C (28.4 F)	n/a	n/a
Dec	26.0 C (78.8 F)	-7.0 C (19.4 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Fort National still stand. 1926 holds the most, with 45.

Standing records at Fort National by the year they were set
Year set	Standing records
1884	34
1885	35
1886	20
1887	33
1888	24
1889	28
1890	38
1892	25
1893	38
1895	28
1897	35
1898	28
1899	34
1900	33
1901	25
1902	20
1903	28
1904	24
1905	30
1906	28
1907	37
1908	27
1909	37
1910	32
1911	10
1912	31
1913	16
1914	24
1915	35
1916	23
1917	33
1919	26
1920	27
1921	32
1922	30
1923	23
1924	28
1925	33
1926	45
1927	23
1928	26
1929	19
1930	35
1931	40
1932	17
1933	33
1934	24
1935	33
1936	34
1937	16
1938	27

All-Time Record Progression

5 new records

5 all-time records were set at Fort National between 28 December 1917 and 9 December 1931. Each dot is a new record.

When Fort National set new all-time records
Date	Kind	Detail
1917-12-28	Record low maximum temperature	Record low maximum temperature -2.0 C (28.4 F)
1923-11-03	Record daily precipitation	Record daily precipitation 106.8 mm (4.2 in)
1923-12-11	Record daily precipitation	Record daily precipitation 107.7 mm (4.2 in)
1925-07-29	Record high maximum temperature	Record high maximum temperature 45.0 C (113.0 F)
1931-12-09	Record daily precipitation	Record daily precipitation 113.0 mm (4.4 in)

Wettest Day of Each Month

Dec: 113.0 mm (4.4 in)

The wettest day on record for each calendar month at Fort National. The most was 113.0 mm (4.4 in) on 9 December 1931.

Record daily precipitation for each month at Fort National
Month	Record daily precipitation (mm)	Date
Jan	107.0 mm (4.2 in)	3 January 1932
Feb	87.0 mm (3.4 in)	28 February 1914
Mar	68.0 mm (2.7 in)	10 March 1928
Apr	81.0 mm (3.2 in)	26 April 1898
May	80.0 mm (3.1 in)	22 May 1910
Jun	45.8 mm (1.8 in)	8 June 1904
Jul	21.6 mm (0.9 in)	8 July 1906
Aug	34.0 mm (1.3 in)	19 August 1934
Sep	84.0 mm (3.3 in)	27 September 1925
Oct	103.2 mm (4.1 in)	16 October 1928
Nov	106.8 mm (4.2 in)	3 November 1923
Dec	113.0 mm (4.4 in)	9 December 1931

Period of Record Coverage

1884 to 1938

53 years of record at Fort National, 1884 to 1938. 6 years have data for under 90 percent of days and are left out of rankings: 1884, 1891, 1894, 1920, 1936, 1937.

Days with data per year at Fort National
Year	Days with data	Share of year	Complete
1884	317	87%	No
1885	333	91%	Yes
1886	357	98%	Yes
1887	363	99%	Yes
1888	363	99%	Yes
1889	342	94%	Yes
1890	359	98%	Yes
1891	1	0%	No
1892	356	97%	Yes
1893	350	96%	Yes
1894	1	0%	No
1895	350	96%	Yes
1897	356	98%	Yes
1898	355	97%	Yes
1899	362	99%	Yes
1900	344	94%	Yes
1901	353	97%	Yes
1902	351	96%	Yes
1903	357	98%	Yes
1904	361	99%	Yes
1905	351	96%	Yes
1906	350	96%	Yes
1907	352	96%	Yes
1908	362	99%	Yes
1909	358	98%	Yes
1910	345	95%	Yes
1911	356	98%	Yes
1912	353	96%	Yes
1913	362	99%	Yes
1914	360	99%	Yes
1915	344	94%	Yes
1916	360	98%	Yes
1917	337	92%	Yes
1919	333	91%	Yes
1920	283	77%	No
1921	340	93%	Yes
1922	354	97%	Yes
1923	351	96%	Yes
1924	354	97%	Yes
1925	347	95%	Yes
1926	354	97%	Yes
1927	334	92%	Yes
1928	347	95%	Yes
1929	342	94%	Yes
1930	336	92%	Yes
1931	346	95%	Yes
1932	347	95%	Yes
1933	334	92%	Yes
1934	350	96%	Yes
1935	340	93%	Yes
1936	254	69%	No
1937	249	68%	No
1938	351	96%	Yes

Latest Records

Latest records at Fort National
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
27 December 1938	Fort National, DZ	daily low max	1.0 C (33.8 F)	3.0 C (5.4 F)	48 years	26 of 100 (Routine)
26 December 1938	Fort National, DZ	daily low min	-2.0 C (28.4 F)	1.0 C (1.8 F)	39 years	19 of 100 (Routine)
25 December 1938	Fort National, DZ	daily low max	1.0 C (33.8 F)	1.0 C (1.8 F)	24 years	14 of 100 (Routine)
24 December 1938	Fort National, DZ	daily low max (Tie)	2.0 C (35.6 F)	tie	50 years	5 of 100 (Routine)
16 December 1938	Fort National, DZ	daily high min (Tie)	10.0 C (50.0 F)	tie	4 years	1 of 100 (Routine)
15 December 1938	Fort National, DZ	daily high min	10.0 C (50.0 F)	1.0 C (1.8 F)	29 years	16 of 100 (Routine)
23 November 1938	Fort National, DZ	daily high min (Tie)	11.0 C (51.8 F)	tie	27 years	3 of 100 (Routine)
12 November 1938	Fort National, DZ	daily high max	24.0 C (75.2 F)	1.0 C (1.8 F)	24 years	14 of 100 (Routine)
11 November 1938	Fort National, DZ	daily high max	24.0 C (75.2 F)	1.0 C (1.8 F)	31 years	16 of 100 (Routine)
10 September 1938	Fort National, DZ	daily low min (Tie)	10.0 C (50.0 F)	tie	28 years	3 of 100 (Routine)
9 September 1938	Fort National, DZ	daily low max	15.0 C (59.0 F)	4.0 C (7.2 F)	21 years	19 of 100 (Routine)
9 September 1938	Fort National, DZ	daily rain	35.0 mm (1.4 in)	3.5 mm (0.14 in)	8 years	10 of 100 (Routine)
31 August 1938	Fort National, DZ	daily low min	11.0 C (51.8 F)	2.0 C (3.6 F)	37 years	21 of 100 (Routine)
29 August 1938	Fort National, DZ	daily rain	9.0 mm (0.35 in)	0.4 mm (0.02 in)	53 years	20 of 100 (Routine)
22 August 1938	Fort National, DZ	daily low max	22.0 C (71.6 F)	2.2 C (4.0 F)	51 years	25 of 100 (Routine)
18 August 1938	Fort National, DZ	daily high min (Tie)	26.0 C (78.8 F)	tie	47 years	4 of 100 (Routine)
3 August 1938	Fort National, DZ	daily high max	39.0 C (102.2 F)	1.0 C (1.8 F)	17 years	12 of 100 (Routine)
25 July 1938	Fort National, DZ	daily high max	41.0 C (105.8 F)	4.0 C (7.2 F)	12 years	17 of 100 (Routine)
21 July 1938	Fort National, DZ	daily high max	41.0 C (105.8 F)	4.0 C (7.2 F)	4 years	15 of 100 (Routine)
19 July 1938	Fort National, DZ	daily high max (Tie)	37.0 C (98.6 F)	tie	13 years	2 of 100 (Routine)

Climate Trend

46 complete years, 1886 to 1938

One stripe for each of 46 complete years at Fort National, 1886 to 1938. Blue stripes are years cooler than the station's own mean of 14.6 C (58.3 F); red stripes are warmer. The coolest year was 1909, at 13.2 C (55.8 F), and the warmest was 1926, at 16.2 C (61.1 F). The strongest colour marks a difference of 1.6 C (2.9 F).

Annual mean temperature at Fort National as warming stripes, 1886 to 1938
Year	Annual mean temperature	Difference from the station mean
1886	13.9 C	-0.71 C
1887	13.9 C	-0.68 C
1888	13.7 C	-0.95 C
1889	13.3 C	-1.29 C
1890	13.4 C	-1.25 C
1892	14.9 C	+0.27 C
1893	15.0 C	+0.37 C
1895	15.3 C	+0.71 C
1897	14.7 C	+0.13 C
1898	14.0 C	-0.59 C
1899	15.4 C	+0.81 C
1900	14.3 C	-0.29 C
1901	13.5 C	-1.07 C
1902	14.6 C	+0.04 C
1903	13.6 C	-1.01 C
1904	14.4 C	-0.22 C
1905	13.8 C	-0.77 C
1906	13.9 C	-0.75 C
1907	14.1 C	-0.50 C
1908	14.3 C	-0.34 C
1909	13.2 C	-1.40 C
1910	13.3 C	-1.28 C
1911	14.0 C	-0.60 C
1912	13.9 C	-0.72 C
1913	14.6 C	+0.03 C
1914	13.8 C	-0.77 C
1915	14.4 C	-0.17 C
1916	15.9 C	+1.25 C
1917	14.0 C	-0.61 C
1919	14.1 C	-0.46 C
1920	15.4 C	+0.81 C
1921	15.1 C	+0.46 C
1922	15.7 C	+1.06 C
1923	14.6 C	-0.01 C
1924	16.2 C	+1.55 C
1925	14.4 C	-0.17 C
1926	16.2 C	+1.55 C
1927	16.0 C	+1.40 C
1928	15.7 C	+1.09 C
1929	14.9 C	+0.29 C
1930	16.0 C	+1.44 C
1931	15.8 C	+1.18 C
1932	15.4 C	+0.81 C
1933	15.6 C	+0.98 C
1934	14.8 C	+0.20 C
1938	14.8 C	+0.24 C

The annual mean temperature here has risen by 0.3 C (0.2 to 0.5) per decade over 1886 to 1938. In Fahrenheit: 0.6 F (0.4 to 0.9) per decade. The slope is a straight line fitted to 46 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Fort National
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.3 C (0.2 to 0.5) per decade	0.6 F (0.4 to 0.9) per decade	1886 to 1938	46	Rise
Mean daily maximum	0.4 C (0.2 to 0.6) per decade	0.7 F (0.4 to 1.0) per decade	1886 to 1938	46	Rise
Mean daily minimum	0.3 C (0.2 to 0.4) per decade	0.5 F (0.3 to 0.8) per decade	1886 to 1938	46	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

1879 to 1938

Yearly extremes at Fort National: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	45.0 C (113.0 F)	1925	39.0 C (102.2 F)	53
Coldest night (TNn)	-7.0 C (19.4 F)	1907	-3.0 C (26.6 F)	52
Wettest day (Rx1day)	113.0 mm (4.4 in)	1931	61.5 mm (2.4 in)	60
Wettest five days (Rx5day)	235.8 mm (9.3 in)	1923	127.0 mm (5.0 in)	56
Longest dry spell (CDD)	110 days	1890	46 days	59

Hottest day (TXx)

The hottest day of the year at Fort National, 1879 to 1938. The record is 45.0 C (113.0 F) in 1925, marked on the chart; the median year is 39.0 C (102.2 F).

Hottest day (TXx) at Fort National by year
Year	Hottest day (TXx)
1879	n/a
1880	n/a
1881	n/a
1882	n/a
1883	n/a
1884	37.0 C (98.6 F)
1885	38.4 C (101.1 F)
1886	38.0 C (100.4 F)
1887	39.0 C (102.2 F)
1888	37.0 C (98.6 F)
1889	37.0 C (98.6 F)
1890	42.0 C (107.6 F)
1891	14.0 C (57.2 F)
1892	38.0 C (100.4 F)
1893	38.0 C (100.4 F)
1894	8.0 C (46.4 F)
1895	38.0 C (100.4 F)
1896	n/a
1897	38.0 C (100.4 F)
1898	41.0 C (105.8 F)
1899	40.0 C (104.0 F)
1900	39.0 C (102.2 F)
1901	36.0 C (96.8 F)
1902	38.0 C (100.4 F)
1903	39.0 C (102.2 F)
1904	37.0 C (98.6 F)
1905	38.0 C (100.4 F)
1906	37.0 C (98.6 F)
1907	37.0 C (98.6 F)
1908	36.0 C (96.8 F)
1909	37.0 C (98.6 F)
1910	38.0 C (100.4 F)
1911	42.0 C (107.6 F)
1912	34.0 C (93.2 F)
1913	38.0 C (100.4 F)
1914	36.0 C (96.8 F)
1915	41.0 C (105.8 F)
1916	41.0 C (105.8 F)
1917	40.0 C (104.0 F)
1918	n/a
1919	36.0 C (96.8 F)
1920	39.0 C (102.2 F)
1921	42.0 C (107.6 F)
1922	42.0 C (107.6 F)
1923	41.0 C (105.8 F)
1924	40.0 C (104.0 F)
1925	45.0 C (113.0 F)
1926	43.0 C (109.4 F)
1927	41.0 C (105.8 F)
1928	40.0 C (104.0 F)
1929	43.0 C (109.4 F)
1930	41.0 C (105.8 F)
1931	41.0 C (105.8 F)
1932	41.0 C (105.8 F)
1933	38.0 C (100.4 F)
1934	40.0 C (104.0 F)
1935	44.0 C (111.2 F)
1936	40.0 C (104.0 F)
1937	42.0 C (107.6 F)
1938	42.0 C (107.6 F)

Coldest night (TNn)

The coldest night of the year at Fort National, 1879 to 1938. The record is -7.0 C (19.4 F) in 1907, marked on the chart; the median year is -3.0 C (26.6 F).

Coldest night (TNn) at Fort National by year
Year	Coldest night (TNn)
1879	n/a
1880	n/a
1881	n/a
1882	n/a
1883	n/a
1884	-2.4 C (27.7 F)
1885	-3.0 C (26.6 F)
1886	-2.0 C (28.4 F)
1887	-3.0 C (26.6 F)
1888	-4.0 C (24.8 F)
1889	-4.0 C (24.8 F)
1890	-4.0 C (24.8 F)
1891	n/a
1892	-2.0 C (28.4 F)
1893	-4.0 C (24.8 F)
1894	n/a
1895	-5.0 C (23.0 F)
1896	n/a
1897	-4.0 C (24.8 F)
1898	-3.0 C (26.6 F)
1899	-1.0 C (30.2 F)
1900	-3.0 C (26.6 F)
1901	-4.0 C (24.8 F)
1902	-4.0 C (24.8 F)
1903	-4.0 C (24.8 F)
1904	-3.0 C (26.6 F)
1905	-6.0 C (21.2 F)
1906	-5.0 C (23.0 F)
1907	-7.0 C (19.4 F)
1908	-6.0 C (21.2 F)
1909	-3.0 C (26.6 F)
1910	-4.0 C (24.8 F)
1911	-3.0 C (26.6 F)
1912	-2.0 C (28.4 F)
1913	-1.0 C (30.2 F)
1914	-5.0 C (23.0 F)
1915	-3.0 C (26.6 F)
1916	-2.0 C (28.4 F)
1917	-7.0 C (19.4 F)
1918	2.0 C (35.6 F)
1919	-2.0 C (28.4 F)
1920	-2.0 C (28.4 F)
1921	-2.0 C (28.4 F)
1922	-3.0 C (26.6 F)
1923	-3.0 C (26.6 F)
1924	-4.0 C (24.8 F)
1925	-1.0 C (30.2 F)
1926	-2.0 C (28.4 F)
1927	-2.0 C (28.4 F)
1928	-2.0 C (28.4 F)
1929	-2.0 C (28.4 F)
1930	-3.0 C (26.6 F)
1931	-3.0 C (26.6 F)
1932	-3.0 C (26.6 F)
1933	-4.0 C (24.8 F)
1934	-5.0 C (23.0 F)
1935	-4.0 C (24.8 F)
1936	-2.0 C (28.4 F)
1937	-3.0 C (26.6 F)
1938	-4.0 C (24.8 F)

Wettest day (Rx1day)

The wettest day of the year at Fort National, 1879 to 1938. The record is 113.0 mm (4.4 in) in 1931, marked on the chart; the median year is 61.5 mm (2.4 in).

Wettest day (Rx1day) at Fort National by year
Year	Wettest day (Rx1day)
1879	56.0 mm (2.2 in)
1880	44.0 mm (1.7 in)
1881	41.0 mm (1.6 in)
1882	60.6 mm (2.4 in)
1883	52.8 mm (2.1 in)
1884	62.4 mm (2.5 in)
1885	38.2 mm (1.5 in)
1886	96.2 mm (3.8 in)
1887	52.0 mm (2.0 in)
1888	45.2 mm (1.8 in)
1889	59.9 mm (2.4 in)
1890	59.0 mm (2.3 in)
1891	0.0 mm (0.00 in)
1892	45.3 mm (1.8 in)
1893	48.3 mm (1.9 in)
1894	27.0 mm (1.1 in)
1895	42.0 mm (1.7 in)
1896	0.0 mm (0.00 in)
1897	66.0 mm (2.6 in)
1898	81.0 mm (3.2 in)
1899	50.0 mm (2.0 in)
1900	68.0 mm (2.7 in)
1901	50.0 mm (2.0 in)
1902	75.8 mm (3.0 in)
1903	46.6 mm (1.8 in)
1904	57.4 mm (2.3 in)
1905	70.2 mm (2.8 in)
1906	64.6 mm (2.5 in)
1907	77.4 mm (3.0 in)
1908	65.0 mm (2.6 in)
1909	42.0 mm (1.7 in)
1910	80.0 mm (3.1 in)
1911	60.2 mm (2.4 in)
1912	30.5 mm (1.2 in)
1913	89.0 mm (3.5 in)
1914	87.0 mm (3.4 in)
1915	55.0 mm (2.2 in)
1916	80.4 mm (3.2 in)
1917	55.2 mm (2.2 in)
1918	0.0 mm (0.00 in)
1919	73.7 mm (2.9 in)
1920	31.7 mm (1.2 in)
1921	65.8 mm (2.6 in)
1922	48.0 mm (1.9 in)
1923	107.7 mm (4.2 in)
1924	88.8 mm (3.5 in)
1925	84.0 mm (3.3 in)
1926	69.3 mm (2.7 in)
1927	67.5 mm (2.7 in)
1928	103.2 mm (4.1 in)
1929	63.0 mm (2.5 in)
1930	76.0 mm (3.0 in)
1931	113.0 mm (4.4 in)
1932	107.0 mm (4.2 in)
1933	63.0 mm (2.5 in)
1934	65.0 mm (2.6 in)
1935	70.5 mm (2.8 in)
1936	50.0 mm (2.0 in)
1937	85.0 mm (3.3 in)
1938	40.0 mm (1.6 in)

Wettest five days (Rx5day)

The wettest five days of the year at Fort National, 1879 to 1938. The record is 235.8 mm (9.3 in) in 1923, marked on the chart; the median year is 127.0 mm (5.0 in).

Wettest five days (Rx5day) at Fort National by year
Year	Wettest five days (Rx5day)
1879	163.3 mm (6.4 in)
1880	75.0 mm (3.0 in)
1881	64.5 mm (2.5 in)
1882	94.4 mm (3.7 in)
1883	133.6 mm (5.3 in)
1884	87.2 mm (3.4 in)
1885	86.4 mm (3.4 in)
1886	131.3 mm (5.2 in)
1887	127.5 mm (5.0 in)
1888	61.8 mm (2.4 in)
1889	78.9 mm (3.1 in)
1890	138.2 mm (5.4 in)
1891	n/a
1892	99.4 mm (3.9 in)
1893	89.1 mm (3.5 in)
1894	n/a
1895	75.6 mm (3.0 in)
1896	n/a
1897	159.9 mm (6.3 in)
1898	192.6 mm (7.6 in)
1899	118.0 mm (4.6 in)
1900	142.5 mm (5.6 in)
1901	82.8 mm (3.3 in)
1902	162.6 mm (6.4 in)
1903	128.7 mm (5.1 in)
1904	132.0 mm (5.2 in)
1905	114.0 mm (4.5 in)
1906	152.1 mm (6.0 in)
1907	133.3 mm (5.2 in)
1908	154.3 mm (6.1 in)
1909	85.5 mm (3.4 in)
1910	156.3 mm (6.2 in)
1911	122.0 mm (4.8 in)
1912	71.1 mm (2.8 in)
1913	147.0 mm (5.8 in)
1914	169.5 mm (6.7 in)
1915	108.9 mm (4.3 in)
1916	223.9 mm (8.8 in)
1917	119.9 mm (4.7 in)
1918	n/a
1919	176.8 mm (7.0 in)
1920	66.6 mm (2.6 in)
1921	119.3 mm (4.7 in)
1922	67.4 mm (2.7 in)
1923	235.8 mm (9.3 in)
1924	204.6 mm (8.1 in)
1925	155.3 mm (6.1 in)
1926	82.0 mm (3.2 in)
1927	178.5 mm (7.0 in)
1928	166.0 mm (6.5 in)
1929	113.5 mm (4.5 in)
1930	200.5 mm (7.9 in)
1931	199.1 mm (7.8 in)
1932	178.4 mm (7.0 in)
1933	92.0 mm (3.6 in)
1934	107.0 mm (4.2 in)
1935	126.5 mm (5.0 in)
1936	74.0 mm (2.9 in)
1937	131.0 mm (5.2 in)
1938	112.0 mm (4.4 in)

Longest dry spell (CDD)

The longest dry spell of the year at Fort National, 1879 to 1938. The record is 110 days in 1890, marked on the chart; the median year is 46 days.

Longest dry spell (CDD) at Fort National by year
Year	Longest dry spell (CDD)
1879	53 days
1880	29 days
1881	36 days
1882	47 days
1883	41 days
1884	46 days
1885	42 days
1886	42 days
1887	69 days
1888	44 days
1889	36 days
1890	110 days
1891	1 day
1892	35 days
1893	44 days
1894	n/a
1895	74 days
1896	1 day
1897	51 days
1898	68 days
1899	33 days
1900	31 days
1901	54 days
1902	46 days
1903	82 days
1904	61 days
1905	40 days
1906	34 days
1907	47 days
1908	28 days
1909	67 days
1910	86 days
1911	57 days
1912	67 days
1913	68 days
1914	54 days
1915	53 days
1916	47 days
1917	95 days
1918	1 day
1919	100 days
1920	9 days
1921	42 days
1922	58 days
1923	85 days
1924	80 days
1925	20 days
1926	33 days
1927	64 days
1928	41 days
1929	52 days
1930	24 days
1931	49 days
1932	23 days
1933	23 days
1934	26 days
1935	53 days
1936	23 days
1937	32 days
1938	55 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

37 years with a frost

Across 37 years with a frost, the median last spring frost at Fort National falls on 19 March and the median first autumn frost on 11 December, which leaves a median of 268 days between them.

Fitted over all years, the growing season changes by +7.3 days per decade at this station.

Frost dates and growing season at Fort National
Measure	Median, all years	Earliest period	Recent period (1898 to 1938)	Recent against earliest	Fitted trend
Last spring frost	19 March	n/a	19 March	n/a	-2.6 days per decade
First autumn frost	11 December	n/a	16 December	n/a	+4.7 days per decade
Growing days	268 days	n/a	270 days	n/a	+7.3 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

53 years, 1879 to 1938

A day with at least 62.6 mm (2.5 in) of rain is expected about once in 2 years. A day with at least 123.0 mm (4.8 in) of rain is expected about once in 100 years.

Rainfall return levels at Fort National: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	62.6 mm (2.5 in)
5 years	80.3 mm (3.2 in)
10 years	91.3 mm (3.6 in)
25 years	104.6 mm (4.1 in)
50 years	114.0 mm (4.5 in)
100 years	123.0 mm (4.8 in)	Longer than the 53 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, 53 years of values from 1879 to 1938.

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: 113.0 mm (4.4 in) in 1931; 107.7 mm (4.2 in) in 1923; 107.0 mm (4.2 in) in 1932.

Download the Data

Data for Fort National standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Fort National 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 2026-10-14. Last revised 14 October 2026 (2026-10-14).